ASTRONOMY
TECHNOLOGY TODAY Your Complete Guide to Astronomical Equipment
VIXEN VC200L • STARIZONA’S MICROTOUCH AUTOFOCUSER WEEKEND DOB BASE PROJECT • SERVOCAT TRACK AND GO-TO SYSTEM
STAR Workshop 2007
Students, amateur and professional astronomers, educators, and commercial designers and manufacturers of small telescopes share their ideas in the rapidly expanding arenas of small telescope engineering development, scientific research, and undergraduate education.
Volume 1 • Issue 4 September 2007 $4.00 US
Cover Story
Contents ASTRONOMY
TECHNOLOGY TODAY This 16-inch, research grade telescope built and owned VIXEN VC200L • STARIZONA’S MICROTOUCH AUTOFOCUSER by Jerry and Cindy Foote, is one of many discussed during WEEKEND DOB BASE PROJECT • SERVOCAT TRACK AND GO-TO SYSTEM the 2007 STAR Workshop held at the California Polytechnic State University’s San Luis Obispo campus in June. The telSTAR Workshop escope utilizes a carbon fiber truss system to maintain pre2007 Students, amateur and cise focus over a wide range of temperatures and the OTA professional astronomers, educators, and commercial is mounted on a short fork to facilitate use in an existing designers and manufacturers of small telescopes share their ideas in the rapidly expanding observatory. It features an Astrosital 2-inch thick primary arenas of small telescope engineering development, scientific figured to f/3.0 by Intermountain Optics and has an effecresearch, and undergraduate education. tive focal length of 55.6 inches. The mount uses a split ring/horseshoe type RA disk. All roller drive systems in RA & Dec are driven by micro-stepped stepping motors with resolution of 0.25 arc seconds per step. An SBIG ST-7e CCD camera is mounted at prime focus on linear bearings driven by stepper motors interfaced to the PC. The telescope also incorporates a Tele Vue Paracorr coma corrector and SBIG CFW-8 filter wheels with BVRI filters. The background image of the Orion Nebula was taken using a Celestron 11-inch SCT, HyperStar lens, and Starlight Xpress SXV-H9C one-shot color CCD camera by Dail Terry and Scott Tucker. A much smaller image of the Nebula was featured in our April issue.
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Your Complete Guide to Astronomical Equipment
Editor’s Note 8
Can’t Always Get What You Want
Volume 1 • Issue 4 September 2007 $4.00 US
Reader Profile 66 Erik Wilcox
Features
11 THE IMAGING SOURCE Announces Astronomy Cameras Blog 12 MEADE INSTRUMENTS mySKY is Now Shipping
14 ASTRO HUTECH Plans Additions to its Lines of Modified Spectrum DSLR Cameras
15 PROTOSTAR Introduces Catalog
41 Vixen VC200L Two Looks at the Visual and Imaging Performance of the Vixen VISAC By Daniel Mounsey and Shawn Hendrix
50 A Banner Month for Astronomy Events Behind the Scenes Look at the SCAE, Green Bank Star Quest, and Epoch 2007 Star Party and Midwest Astro Imaging Conference
11 R. F. ROYCE PRECISION OPTICAL COMPONENTS Tests DK Prototype
15 AIC 2007 Examines Advanced CCD Imaging
37 Integrating Video Cameras A Look at These Popular Astro Imaging Cameras and the CCD Technology Behind Them By Owen Sage
45 The Weekend Dob Base Project Building a Dob Base Made Easy Using Your Current Dob Base as a Template! By Erik Wilcox
Industry News
15 STARLIGHT INSTRUMENTS Announces Limited Lifetime Warranty
57 Starizona MicroTouch Autofocuser Impatience is the Mother of Invention. By Scott Tucker
16 SPRINGER New Introductions in Patrick Moore's Practical Astronomy Series
62 Brainless Astronomy 101 Upgrading to a ServoCAT Track and Go-To System By Jack Huerkamp Astronomy TECHNOLOGY TODAY
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Contributing Writers Russ Genet is the Director of the Orion Observatory, teaches astronomy at Cuesta College in San Luis Obispo, California, and is a Research Scholar in Residence at nearby California Polytechnic State University. Author of a dozen books and over one hundred scientific papers, he pioneered the world’s first fully robotic observatory (featured in the PBS special The Perfect Stargazer), and was the 51st President of the Astronomical Society of the Pacific.
Shawn Hendrix is a Technical Sales Rep for Ryan Herco Flow Solutions and lives in Santa Clarita, California, with wife, Ramona, and children, Trevor and Megan. Shawn is a regular at Mt. Pinos events and has been in love with God's Creation, the Universe, since his first views through a Celestron 8 at age 13.
Jack Huercamp is the owner of Jack’s Astro Accessories which distributes the MallinCam HyperPlus in the U.S. and is a member of the Pontchartrain Astronomy Society.
Daniel Mounsey is perhaps best known for his extensive and prolific eyepiece reviews. Daniel is also the principal of Astro Custom Cases, the "Dr. D" of Woodland Hills Camera & Telescopes, and a regular at the monthly Mt. Pinos events. He also enjoys writing for CloudyNights.com and both planetary and deep sky observing.
Contents
New Products
18 FAR LABS “Look Here Device” and Eclipse Red Illuminated Keyboard
21 MARKS PRODUCTS FinderVISION Video Viewfinder 21 OPTEC Adds Ultra WideField 0.7XL to its NextGEN Series Telecompressors 22 ADIRONDACK ASTRONOMY Astrovid Voyager X
Owen Sage started observing with a home made 4-inch Newtonian on a pipe fitting mount at the age of 9. The astronomical epiphany came when he recognized that the mountains on the Lunar limb were like the mountains he had seen here on earth. His major in college and graduate school was astronomy and that, plus a lifetime of computer/electronic engineering, combine to make astronomical instrumentation his specialty. Scott Tucker grew up in Michigan where one rare night the clouds finally parted and unveiled the stars. He works at Starizona where he writes educational guides for the Web, helps develop new products, shares his expertise on imaging and love of the night sky with the public, and even finds time to draw astronomical cartoons.
Erik Wilcox works for a natural foods distributor in South San Francisco,
California, and is a long-time moderator on the popular astronomy forum, “Cloudy Nights”. He enjoys star parties and public outreach, and, in addition to amateur astronomy, he spends his time playing in a rock band.
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22 STARLIGHT INSTRUMENTS Feather Touch Adapted to Orion's SkyQuest Dobsonians 23 MAXFACTORY Master AutoStar 24 ASTROHUTECH New Borg Astrographs 25 CNC SUPPLY 2-inch Prime Focus Adapter for Canon EOS DSLR Cameras 25 UNIHEDRON Sky Quality Meter
ASTRONOMY
TECHNOLOGY TODAY
Volume 1 • Issue 4 September 2007 Publisher Stuart Parkerson
Managing Editor Gary Parkerson
Associate Editors Russ Besancon Karol Birchfield
Art Director Lance Palmer
Staff Photographer Jim Osborne
Web Master
Editor’s
Note
Gary Parkerson, Managing Editor
When I was a young man, another who seems to have gotten everything he ever wanted, sang that we can’t always have what we want. He consoled though that if we try, sometimes we’ll find that we get what we need. So far, Astronomy Technology Today has been an exercise in starting out with one very specific desire and ending with something completely different – usually something much better. As always, the law of unintended consequences effects everything we do here.
James Bobbit
3825 Gilbert Drive Shreveport, Louisiana 71104 info@astronomytechnologytoday.com www.astronomytechnologytoday.com Astronomy Technology Today is published monthly by Parkerson Publishing, LLC. Bulk rate postage paid at Dallas, Texas, and additional mailing offices. ©2007 Parkerson Publishing, LLC, all rights reserved. No part of this publication or its Web site may be reproduced without written permission of Parkerson Publishing, LLC. Astronomy Technology Today assumes no responsibility for the content of the articles, advertisements, or messages reproduced therein, and makes no representation or warranty whatsoever as to the completeness, accuracy, currency, or adequacy of any facts, views, opinions, statements, and recommendations it reproduces. Reference to any product, process, publication, or service of any third party by trade name, trademark, manufacturer, or otherwise does not constitute or imply the endorsement or recommendation of Astronomy Technology Today. The publication welcomes and encourages contributions; however is not responsible for the return of manuscripts and photographs. The publication, at the sole discretion of the publisher, reserves the right to accept or reject any advertising or contributions. For more information contact the publisher at Astronomy Technology Today, 3825 Gilbert Drive, Shreveport, Louisiana 71104, or e-mail at info@astronomytechnologytoday.com.
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Don’t give an equipment addict an equipment magazine. Speaking of getting what we want, we received this recently from Chuck in Carlsbad, California: “Well, the first three issues [a back-issue shipment] arrived a couple of days ago, and I’m almost finished with my first pass. I’m impressed! But, I’m afraid that the magazine will cost me MUCH more than $12.00 per year. I'm already in the hole for maybe 50 times that figure! And I haven't finished ordering ‘stuff’ – good thing I don't need another OTA, or I’d be out kilobucks! Keep up the good work.” I feel your pain Chuck, and then some. Put yourself in my position: that of confessed astro-equipment addict (who else would start an astro-products print magazine?) who now must resist an endless parade of the most diabolically tempt-
ing astro-stuff yet devised by man! (Yes, it’s a long, lonely road we walk Chuck.) Some of you will appreciate the fix Chuck and I find ourselves in. But fear not - I’ve developed a 12-step program (actually a ‘12-month’ program) that, while not insuring total abstinence, does help manage the obsession. This most rational plan is a personal lottery: I put each new wish-list item on a slip of paper, put them all in a hat, and permit myself to draw only once a month – so far I’ve managed to miss the GRAND PRIZE, but it’s in there somewhere and I may get lucky yet! Prudence requires that I load the hat with lots of single and double digit items (magazine start-ups are expensive too). Those of you who endure the direct supervision of a spouse, or “significant other,” may require two hats. Good luck with that. Oh, the 12-month aspect comes into play when I empty the hat every 12 months. We’ll be introducing lots of new stuff every year and the hat’s only so big. Do you really want that? When we announced the magazine, but before any of you had seen the first issue, we got lots of mail explaining what potential subscribers wanted to see in a publication dedicated to astro-products. What some of you wanted is essentially an astronomy version of Consumer Reports, complete with content free of the influence of advertisers. Frankly, if such a pub-
lication existed, I’d be one of its first subscribers. I too would like to see all modern Apos tested head-to-head by independent and unbiased experts using the most sophisticated testing methods available to the optics industry. I too would like to see numerous, random samples, in every available aperture, of the craftsmanship of the likes of Zambuto, Royce and Kennedy, all subjected to equally rigorous testing and trials. I too would like to see independent verification of every critical aspect of every modern eyepiece. And, much more. What many fail to consider is that such a publication doesn’t merely entail purchasing all evaluated equipment anonymously at full retail prices. It also requires paying for the paper, the printing, the postage, the experts, the testing equipment and testing facility, not to mention the creative staff, the office for the creative staff, the insurance, the taxes, the travel expenses, etc. And who would pay for all of that? You the subscriber, that’s who. Unfortunately, the subscription price that an audience that is numbered in the tens of thousands, rather than millions, would have to pay to cover those costs is much more than most are in fact willing to pay – not even with the cost savings of newsprint. As much as I’d like to see such a publication, I now recognize that it wouldn't be much fun to produce (I don’t look good in a lab coat and never much liked carrying a clip board), much less read. On the other hand, the format into which our original plan for ATT has evolved is fun to produce and, we hope, equally fun to read – at least for astro-products enthusiasts. We want accuracy! As we obsessed over editing of our inaugural, “April,” issue, my brother and publisher, Stuart, cautioned that, try as we might, we’d never manage an error free issue. And, try as we might, he’s been
proven right. The good news is that we’ve managed to escape with relatively few errors, but some of the few that did slip through have been fairly embarrassing. The error I dislike most is spelling someone’s name incorrectly, or worse, misnaming them entirely. Almost as bad is misnaming a product. So, I was ashamed to learn that on page 21 of the August issue we repeatedly referred to the Catseye Field Case by Wood Wonders as the “Tool Drawer.” I’ve no idea how I managed that mistake or how we managed collectively to miss it. We also neglected to let you know that Tony Hallas took the photo of Tom Osypowski of Equatorial Platforms that graced the cover of our August issue. Similarly, our brief coverage of the Texas Star Party in that issue mentioned a presentation by Al Nagler concerning Tele Vue’s ground breaking Ethos eyepiece line. Unfortunately, I did not leave well enough alone and included this: “It may not be the perfect eyepiece, but, oh they are getting so very close!” That sentence prompted some to inquire exactly what it was that I found imperfect in the prototype and I was reminded, once again, that words have meaning and I should be much more careful in choosing mine. What I meant was that the Ethos was as close to eyepiece perfection as I’ve experienced. Some of you may still want to know why it, or any other eyepiece, isn't absolutely “perfect” and I'll hedge by claiming that eyepiece perfection is a somewhat personal measure. My perfect eyepiece would offer a 100 degree apparent field of view (now that I know it can indeed be done), optimum eye-relief, the clarity and throughput of the finest planetary eyepiece, no perceivable aberration, AND variable focal length of 2.5 mm to 26 mm (I can afford only one). Obviously, the new Ethos is not
yet available in “zoom” and, therefore, does not meet my admittedly narrow and artificial definition of “eyepiece perfection.” (I should quit before I'm in even more trouble.) Be careful what you wish for - it might be unrecognizable by the time you get it! Many of you will recall that we have anxiously awaited this, our fourth issue, as the first that would be eligible for shipment via the Postal Service’s “subscriber periodical” or “requestor” classification, rather than the lower delivery priority “bulk” or “standard” rate category to which the first three issues were relegated. You may also remember that it was our offer of a limited number of free, three month trial subscriptions that prejudiced those early issues. Well, now that we’ve survived delivery of the first three issues (barely) and this issue is indeed eligible for the higher priority rate classification, the Postal Service has changed the rules of that and other classifications effective June, 2007, and we’re back to square one. Meanwhile, we meet regularly with the Postal Service to resolve delivery issues and much progress has in fact been made. We will post regular notices of the changes we are making with regard to delivery of the magazine at www.tech.groups.yahoo.com/group/astro nomytechnologytoday and hope you will join us there. And so… I hope you enjoy this issue of Astromony Technology Today as much as we did bringing it to you. The above forum is a perfect place for you to let us know what you think of our efforts and to share your recommendations for future issues. Some of you have already taken the opportunity to guide future articles and those articles are now in the works.
Astronomy TECHNOLOGY TODAY
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The Supporting
CAST 20/20 Telescopes and Binoculars/EPOCH 2007 www.2020telescopes.com page 20
The Companies And Organizations That Have Made Our Magazine Possible!
We wish to thank our advertisers without whom this magazine would not be possible. When making a decision on your next purchase, we encourage you to consider these advertisers’ commitment to you by underwriting this issue of Astronomy Technology Today.
Celestron www.celestron.com page 2, 71
Jack’s Astro Accessories www.waningmoonii.com page 48
Round Table Platforms www.roundtableplatforms.com page 46
Clement Focuser www.clementfocuser.com page 16
JMI Telescopes www.jmitelescopes.com page 13
Scope Stuff www.scopestuff.com page 58
Clickodometer www.clickodometer.com page 25
Khan Scope Centre www.khanscope.com page 58
Scope Trader www.scopetrader.com page 12
Cloudy Nights www.cloudynights.com page 56
Meade Instruments www.meade.com page 4, 69
SkyShed Observatories www.skyshed.com page 60
CNC Supply www.cncsupplyinc.com page 34
Moonbeam Website Development www.moonbeam.scopetrader.com page 58
Starizona www.starizona.com page 11
Durango Skies www.durangoskies.com page 53
Obsession Telescopes www.obsessiontelescopes.com page 17
Starlight Instruments www.starlightinstruments.com page 31
Equatorial Platforms www.equatorialplatforms.com page 61
Oceanside Photo and Telescope www.optcorp.com page 40, 70
Starry Night Lights www.starrynightlights.com page 18
FAR Laboratories www.farlaboratories.com page 59
Optec www.optecinc.com page 22
StellarCAT www.stellarcat.com page 19
AstroTrac www.astrotrac.com page 47
Farpoint Astronomical Research www.farpointastro.com page 67
Ostahowski Optics www.ostahowskioptics.com page 24
Stellarvue www.stellarvue.com page 63
ATS Piers www.AdvancedTelescope.com page 61
Fishcamp Engineeering www.fishcamp.com page 21
Peterson Engineering www.petersonengineering.com page 58
Teton Telescope www.tetontelescope.com page 23
Blue Planet Optics www.blueplanetoptics.com page 72
Glatter Collimation www.collimator.com page 42
Pier 42 Design & Fabrication www.pier42design.com page 34
The Pines Optical Shop pinesop@aol.com page 12
Bobs Knobs www.bobsknobs.com page 28
Great Red Spot Astronomy www.greatredspot.com page 23
ProtoStar www.fpi-protostar.com page 16
Woodland Hills Telescopes www.whtelescopes.com page 14
Catseye Collimation www.catseyecollimation.com page 46
The History Channel www.history.com page 26
Adirondack Astronomy www.astrovid.com page 12, 18, 21, 24 Astro Domes www.astrodomes.com page 53 Astro Gizmos www.astrogizmos.com page 15, 43 Astro Hutech www.hutech.com page 10, 26 Astro Physics www.astro-physics.com page 29, 49 AstroShorts www.astroshorts.com page 47 AstroSky www.astrosky.homestead.com page 24
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INDUSTRYNEWS
R. F. ROYCE PRECISION OPTICAL COMPONENTS Tests DK Prototype
Reported in our April issue was Robert Royce's announcement that his company was planning production of a 10-inch closed tube Dall-Kirkham and a 12.5-inch open tube DK. Since that report, Royce has completed initial construction of the prototype and begun testing of the 10-inch model. Attendees of the 2007 Star Quest in Green Bank, West Virginia, were treated to views through the specialized instrument. High magnification testing on Vega demonstrated the effectiveness of the unique curved, three-vane spider arrangement at virtually eliminating diffraction spikes, while images of Jupiter at magnifications to 400 times gave tantalizing glimpses of the design’s capabilities in moments of exceptional seeing. The design incorporates simple, but effective baffles that produced superior image contrast against a very dark background, despite the prototype’s unpainted tube interior. The prototype was also equipped with an exhaust fan that pulls air across the back and front of the primary mirror simultaneously, producing equilibrium in as quickly as 10 to 15 minutes. Since the Green Bank event, Royce has anodized and painted the tube assembly and tweaked its baffling, including testing of a new antireflective material to eliminate all residual internal grazing reflections. For more information on the progress of this project, visit www.rfroyce.com.
THE IMAGING SOURCE Announces Astronomy Cameras Blog The Imaging Source is a multi-national enterprise with branches in Charlotte (USA), Taipei (Taiwan) and Bremen (Germany). It has been manufacturing imaging products for scientific, industrial and medical applications for more than twenty years and in January, 2007, launched a new line of cameras, aimed exclusively at amateur astro-photographers. Its DMK FireWire Cameras are already enjoying a lot of success within the astronomy community and quickly building a loyal following. ATT plans to include a detailed report of one of these popular imaging systems soon.
To facilitate exchange of company and user news and information about the DMK FireWire Cameras, The Imaging Source has established www.astronomycamerasblog.com. The site has been surprisingly active since its inception and entries include tips for beginners, reviews, and many examples of truly stunning images taken with the cameras. The Imaging Source DMK FireWire Cameras are available from Adirondack Astronomy - www.astrovid.com, Oceanside Photo & Telescope www.optcorp.com, and Woodland Hills Camera - www.whtelescopes.com.
Astronomy TECHNOLOGY TODAY
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INDUSTRYNEWS
MEADE INSTRUMENTS mySKY is Now Shipping Meade’s long anticipated mySKY began arriving in showrooms in late July. Dealers report that demand for the new, easy to use, night sky guide has been high and may exceed initial supply, so available units are being distributed on a first-come, firstserved basis. Most dealers allow preordering to secure a place in line. mySKY works its magic through a combination of 12 channel GPS receiver, electronic accelerometers, and magnetic north sensors that combine to provide highly accurate calculation of the device’s location and pointing orientation. No user input is required; simply turn it on and it automatically acquires all data required to support its numerous functions. mySKY boasts an upgradable database of over 30,000 objects. mySKY delivers celestial information in a true multimedia format. Sight, sound and tactile feedback are simultaneously stimulated by its unique integration of LCD display, clear, concise audio and intuitive pointing design. Student lesson plans generally combine only visual and audible information to hold students’ attention, leaving the growing ranks of tactile learners little to focus on.
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Astronomy TECHNOLOGY TODAY
By incorporating a pointing design that is as natural as aiming an index finger and asking, “What’s that?” mySKY has the potential to make astronomy relevant to all.
Visit www.meade.com to experience the audio/visual aspects of mySKY. But, to enjoy the full experience, you’ll have to put one in your hand and point.
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INDUSTRYNEWS
ASTRO HUTECH Plans Additions to its Lines of Modified Spectrum DSLR Cameras Among the many new additions that Astro Hutech is plannning to add to its growing lines of astrophotography instruments are four new Modified Spectrum DSLR cameras that offer a feature that is sure to capture the attention of astrophotographers.
This key feature permits framing and focusing with each camera’s large LCD monitor, rather than the often awkward to reach viewfinder. Some combine the feature with an enlargement function, greatly enhancing the LCD monitor assisted focus accuracy. The ability to frame and focus via the LCD screen moves astrophotographers much closer to realizing the stand-alone potential of the DSLR package, eliminating the need to set up a laptop in the field. These additions to Hutech’s Modified Spectrum lines include the Fuji S5Pro, with its upgraded “Super CCD” sensor, the Olympus E410, with 10-Megapixel performance in a lightweight package, the Panasonic L-1, and Canon's 1D MarkIII. For more information on Hutech Modified Spectrum camera options, visit www.astrohutech.com.
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Astronomy TECHNOLOGY TODAY
INDUSTRYNEWS
AIC 2007
PROTOSTAR
Examines Advanced CCD Imaging The 2007 Advanced Imaging Conference will be held October 26-28 at the San Jose, California, DoubleTree Hotel. Conveniently located within 5 minutes of the San Jose Airport, it offers special lodging rates to conference attendees. This event is designed to provide a forum for the discussion and dissemination of information to CCD imagers who are serious about their work, and share a common level of interest in the topic. Both advanced imagers and beginners will find the information useful and the speakers stimulating. The presentations will cover hardware/software, techniques for processing image data and the science related to gathering CCD images with dedicated astronomical CCD cameras. The stellar cast of presenters include: Adam Block, Rob Gendler, Don Goldman, Neil Fleming, Steve Cannistra, Dr. Mike Bolte, Daniel Verschatse, Chris Schur, Ken Crawford, Russ Croman, and Jay GaBany. Topics range from image composition to post acquisition processing. The conference will honor Rob Gendler with its annual Hubble Award. Scheduled activities include a variety of workshops and an extensive array of exhibits featuring the products and technology we just can’t get enough of from Santa Barbara Instrument Group, RC Optical Systems, Software Bisque, Anacortes Telescope, Apogee Instruments, CCDWare Publishing, NASA’s Global Telescope Network, AstroDon Imaging Products, Kitt Peak Visitor’s Center Advanced Observing Program, Caelum Observatory, DC3 Dreams SP, Diffraction Limited, AstroTech Engineering, Astro Hutech, Finger Lakes Instrumentation, Fishcamp Engineering, Oceanside Photo & Telescope, Yankee Robotics, PlaneWave Instruments, QSI, Sky and Telescope Magazine, and more. For more information please visit www.aicccd.com.
2007 Catalog If you are reading this magazine, chances are that you, as do we, enjoy and rely on the shear volume of information available from digital, on-line sources, but still prefer the tactile sensations that are only available when holding the pages in your hands. We were therefore thrilled to receive our new ProtoStar 2007 Catalog in all its full, four-color, print glory. For those who can't resist zoomable, high-resolution images, the catalog is available in 'pdf' download from www.fpi-protostar.com. But, those keen observers of at risk traditions will be relieved to know that ProtoStar ships its print version worldwide. Other information available by download from ProtoStar's Web site includes up-to-date product manuals and installation guides.
STARLIGHT INSTRUMENTS Announces Limited Lifetime Warranty Starlight Instruments, maker of the famous Feather Touch Focuser, now offers a warranty that recognizes the unsurpassed excellence of its products. Starlight’s plain English version of its Limited Lifetime Warranty includes, “If at any time any part of the focuser fails or wears out prematurely we will replace it free of charge…From our experience it is unlikely that you will need this service. That has always been our goal.” Yes, the lawyers have added the usual boilerplate fine print, including caveats for cases of misuse, mishandling, or modification, but the bottom line is that original owners of Starlight Instruments products can rely on a lifetime of dependable, precision focusing for their one time, modest investment.
Astronomy TECHNOLOGY TODAY
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INDUSTRYNEWS
SPRINGER New Introductions in Patrick Moore’s Practical Astronomy Series Several new books are soon to be released by Springer for this fall as part of Patrick Moore’s Practical Astronomy Series. The book series bridges the gap between the introductory books and specialized technical publications. Observing the Sun with Coronado Telescopes by Philip Pugh is a 220 page softcover title to be released in September. The book is an introduction to H-alpha solar observation and covers a range of equipment from entry level to advanced, with emphasis on affordability. It offers detailed sections on imaging and image-processing and includes superb amateur images of the
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Astronomy TECHNOLOGY TODAY
Sun in H-alpha. As the title suggests, the book discusses the introduction of the Coronado range of solar telescopes and filters which heralded the ‘coming of age’ of amateur solar astronomy. Before then, solar astronomy was mostly white-light only. Hydrogenalpha systems were expensive and difficult to use, but today products like the Coronado PST (Personal Solar Telescope) mean that today’s amateur solar observers can see – and image – sunspots, flares, prominences, plage, filaments, and active regions of the Sun, all in amazing detail. The book explains specialist techniques designed to get the best out of a Coronado solar telescope and Pugh has assembled a team of contributors who show just how much solar work can be done with affordable solar viewing equipment. The Far Side of the Moon: A Photographic Guide by Charles J. Byrne is a 230 page hardcover to be released in November. The book is a companion to Byrne’s award-winning Lunar Orbiter Photographic Atlas of the Near Side of the Moon (Springer, 2005). It provides comprehensive coverage of the far side of the Moon, and is the first book that collects photographs from all five Lunar Orbiter missions: Clementine, Apollo, Luna, Zond, and Nozomi. As in the previous book, the scanning artifacts of the Lunar Orbiter photos have been cleaned. The photographs show each part of the far side in the most favorable resolution and
sun angle. There are many high-altitude oblique photos that provide a feeling of being in space; this book is more like a photographic tour of the far side than an atlas. The striking differences between the near and far side have been a major mystery for astronomers but this book suggests an explanation: a massive early impact on the near side produced the Near Side Megabasin; an impact so large that its rim is on the far side. The floor of this basin established the canvas for the portrait of the Man in the Moon and its ejecta prepared the far side for the rugged array of basins and craters shown in these photos. Since many professional and amateur astronomers direct their telescopes to the near side of the Moon; these photos provide a unique opportunity to become familiar with the far side! The book includes a free CD which contains all the enhanced and cleaned photographs for screen viewing, lectures, etc. My Heavens! The Adventures of a Lonely Stargazer Building an Over-the-Top Observatory is 220 page softcover that will be available in November. It is written by Gordon Rogers, a qualified building surveyor, who looks at the planning, building and construction of an observatory from a professional viewpoint. Whether you might want to undertake building an over-the-top dome observatory yourself, or not, you are sure to enjoy this informative tale, told with humor and humility, of Rogers’ torturous but ultimately rewarding experience with building for himself, attached to his own home, a fancy and sophisticated dome observatory, just for the pleasure of sky watching on beautiful nights (of which there are far too few in England!). Rogers details the thinking and planning
INDUSTRYNEWS that went into this venture, and the options considered and rejected. Learn about the choices and mistakes made along the way and share in the author’s frustrations and triumphs as he completed this project of a lifetime For those with more modest ambitions, the book offers many hints, tips and design features for smaller observatories. Guide to Observing Deep-Sky Objects: A Complete Global Resource for Astronomers is a handy reference for all amateur astronomers. This 190 page softcover book by Jeff Farinacci will be available in November. The book contains, for each constellation, (1) a star chart showing the Bayer labels, (2) a table for many of the stars in the constellation, along with their positions and magnitudes, and (3) a table of the major deep-sky objects in the constellation, with relevant observational data. Facing pages provide unique year-long graphs that show when the constellation is visible in the sky, which allows the user to
quickly determine whether a given constellation can be seen, and when the best time to see it will be. The CD-ROM features a PC program that produces a fully-customized list of the deep-sky objects that are visible in the sky at a user-determined time and place, for any location on the Earth. The list can be printed out to provide convenient (and disposable!) printed lists that the practical astronomer can take to his telescope for each observing session. Available in October, Lights in the Sky: Identifying and Understanding Astronomical and Meteorological Phenomena by Michael Maunder is a softcover title that provides a truly comprehensive guide to observing, identifying, and imaging sky glows and other unusual atmospheric/astronomical phenomena, in both the night
and daytime skies. Amateur astronomers spend a lot of their time observing the sky, but not everything up there is necessarily an astronomical phenomenon. Nor is everything immediately identifiable. How many people can tell the difference between a Sun Dog and a Glory - both meteorological phenomena? Or between the Zodiacal Light and the Gegenschein, which are astronomical? If, as a practical observer, you want to be able to identify what it is when you are faced, for example, with the Specter of the Brocken - or with an unidentified flying object that is...well, unidentified... then Lights in the Sky will provide all the practical scientific information you need. To learn more about these and other great new astronomy titles go to www.springer.com.
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FAR LABS Announces “Look Here Device” and Eclipse Red Illuminated Keyboard
ASTRONOMY
TECHNOLOGY TODAY
You’re involved in one of your favorite activities, public outreach, and you’ve pointed to that same confusing array of protrusions for the hundredth time. You point to the eyepiece and tell the little boy who’s finally getting his turn, “Look here.” The young man places his forefinger on the eye lens and asks, “Here?”, and you think, "There must be a better way!” Now there is. Trust FAR Labs to solve even your smallest astro problems. Its new “Look Here Device” does exactly what the name implies: it is used at star parties to show the uninitiated where to look. The unit consists of a red illuminated collar that is placed around the eyepiece eye lens. Push a button on the handheld controller and the collar lights up to show your guest exactly where to look. Release the button and the collar darkens to permit glare free viewing. It’s simple, it's effective, and at only $25.95, is inexpensive. Problem solved!
You’re hunched over a computer, straining to find the backspace key, and guided only by the purposefully dim, red glow of a night vision optimized CRT or LCD monitor. Once again, you think, “There must be a better way!” and once again FAR Labs provides an answer. Its Eclipse Special Edition Red Illuminated Keyboard is USB internally back-illuminated with Red LEDs. While the Eclipse is perfect for use in astronomy, it is also appropriate for night navigation, security, or any other uses that require the use of a PC in the dark while needing to preserve dark adaptation. The unit weighs only 2 pounds, 5 ounces and includes a 6-foot cord. FAR Labs price for this indispensable device is only $49.95, plus shipping. The well made, heavy duty keyboard offers a standard 104 key layout and features a detachable wrist rest, big rubber feet to prevent slipping and flip up legs for adjusting the keyboard angle. The keys are produced by first coating with a metallic titanium colored material which is then laser removed to reveal the key legend. This produces a high contrast image when backlit by the red LED inside of each key. The keyboard includes a dimming control that adjusts LED brightness or turns them on and off. Problem solved again! For more information on both products, visit www.farlaboratories.com.
Sky Friendly Outdoor Lighting www.StarryNightLights.com
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Astronomy TECHNOLOGY TODAY
With the Stealth of a Leopard, The Speed of a Cheetah, and the Power of a Lion... Come join the ServoCAT Pride! Increase your ability to see fainter objects, to see more detail or just to enjoy the Universe as it was meant to be enjoyed....
The NEW ServoCAT Track and GOTO system.... available as a RETROFIT kit for YOUR Telescope! Install today - USE IT TONIGHT! Close to 600 shipped to date on scopes from 8" to 41.2"! Equatorials as well! FEATURES: • Installable BY YOU in hours... Now includes an INSTALLATION VIDEO! • Also INSTALLATION SITES where WE install!: Arizona, NC, Texas, and California! • Tracks EVERYWHERE, ALL THE TIME! Totally silent tracking. • Can track Sidereal as well as Planets, Comets, Even Space satellites (DSC dependent) • Manual operation without re-aligning included! DIY kits from $599, Complete kits starting at $1299! • Works in conjunction with either an Argo Navis or Sky Commander DSC. NO PC/LAPTOP REQUIRED! • HIGHLY accurate tracking (AutoCALibrate mode to PRECISELY track) even at 1000x, 1500 even 2300x! • GOTO 30,000 objects OR built in GOTO from ANY Planetarium program, Planning software, or even PDA's • True Spiral SearchTM capability BUILT IN! Local Sync for arcminute accuracy, Slip Return for public sessions. • Wired Handpad provides 6 speeds that you can set to YOUR desire! Wireless handpad available as well! • SMOOTH tracking ... powerful SLEWING at speeds of 5, 6 even 8+ degrees/sec - YOU SET what YOU want! • EASY TO USE - just align your scope as normal and use it! Nothing else to do! • Software configurable limits (easy Windows program) - no "Horizon" hassles. • AutoGUIDE capable for long term imaging using a standard CCD AG; also use with the new VIDEO cameras! • Light weight - no HEAVY platform to carry around, no added space/height needed, resetting, or awkward angles. • FULLY plug and play - no wiring to take care of. RELIABLE and FULLY PROTECTED!! 2 Year warranty! • Simple Windows config program, we can even ship fully configured so NO programming needed! • Low power consumption, runs off 12V or available 120V supplies. • OPTIONS: include Wireless 232 to control your scope from hundreds of feet away, Powered Ground Board option for no tangle or battery hassles, CATtail Stalk for convenience in holding your DSC and handpad. • FACTORY INSTALLED ON: Obsession, StarStructure, Plettstone, Discovery, SpaceWalk, and many others!
SCOPE RENTALS! SCOPE RENTALS! SCOPE RENTALS! Also: Desert Coyote Observatory with 12.5" and 30" ServoCAT scopes for rent in DARK SE Arizona (7th mag skies) at reasonable rates. RV available as well! Call for availability. We also sell: Argo Navis DSC - the most powerful Digital Setting Circle available M20 image courtesy of Jerry Pinter, taken with a homemade 18" dob, Canon EOS 20dA, w/ServoCAT StellarCAT, 1460 N Clanton Ave, Sierra Vista, AZ 85635 520.432.4433
www.StellarCAT.com
The staff of 20/20 Telescopes would like to thank everyone who made Epoch 2007 and the 2007 Midwest Astro-Imaging Conference a resounding success! We were blessed with clear skis and nearly 300 attendees who enjoyed a week full of observing, daytime excursions, product demonstrations, seminars, and of course the camaraderie of other fellow amateur astronomers! We appreciate the following vendors who displayed the latest, greatest astro-technology: Astro-Acres, SkyInsight, TeleVue Optics, Poly-Dome, IP4AP, Stark Labs, Caelum Observatory, and Great Red Spot Astronomy Products. The 2007 Midwest Astro-Imaging Conference was also a resounding success! Our thanks goes to Astrophotography Insight’s Al Degutis and co-host Jeff Terry of the Illinois Institute of Technology for coordinating the conference. We would also like to thank St. Joseph's College for providing the host site for the event. And, of course, our thanks goes to the following presenters: Al Nagler, Jim Burnell, Adam Block, Alan Chen, Alan Friedman, Warren Keller, Craig Stark, and Greg Piepol. So, by popular demand, EPOCH 2008 and The 2008 Midwest Astro-Imaging Conference will be during the week of July 27 to August 3, 2008. We promise it will be bigger and better! Thanks again to our many friends and supporters – we’ll see you next year! www.2020telescopes.com
NEWPRODUCTS
MARKS PRODUCTS FinderVISION Video Viewfinder FinderVISION is a video system that is designed specifically for use as a viewfinder for astronomical telescopes. The system allows the user to remotely view a 5 x 6 degree (at 50-mm fl), or larger, field of view with electronic crosshairs. The electronic crosshairs can be moved to any location within 90% of the FOV of a video camera image. The control unit features two video inputs and two video outputs. The electronic crosshairs can be switched between the two outputs as well as switched between centered or moveable. Crosshair brightness can be adjusted from black to white, and any shade of gray in between. The control box can be used to superimpose electronic crosshairs on any video monitor and any video source including RS170, NTSC & PAL video
formats. When used with a high quality B/W monitor, the video viewfinder can detect > 9.5 mag. stars under good conditions. It is easy to recognize star fields and to compare with star charts or computer planetarium programs. It can also see deep sky objects such as M31, M13, M92 and M42. When using a fork mounted scope, the video viewfinder can be used no matter where the scope is pointed. The FinderVISION also can find and align to the alignment stars for your Go-To scope. For high magnification video planetary photography, the video viewfinder makes finding the planet much easier. Use a video planetary camera and scope with the video crosshairs as a guide scope system for piggyback photography.
The FinderVISION components include the Video Crosshair Generator/Control Box, Power Supply, 12vdc Cigarette Cord and AC Adapter. For more information go to www.findervision.com.
OPTEC Adds Ultra WideField 0.7XL to its NextGEN Series Telecompressors nearly diffraction limited. This four-element The NextGEN Series is the second gensystem also maintains the parfocality of the eration of telecompressors designed by telescope and the image field is highly corOptec. The first generation was available for rected to 18-mm diameter accommodating the early CCD cameras such as the SBIG STlarge format CCD cameras. Like the other 6 and Meade 416. Improvements in reducers in the NextGEN series, all surCCD designs warranted the redesign faces have a broadband multilayer of Optec telecompressors. These coating optimized for the 450 - 650 designs have been optimized by nm passband of the optic. the premier Zemax optical The existing Next GEN Maxfield design program and made to 0.33 and WideField 0.50X Optec telethe highest optical standards. compressors are still being produced and All optical surfaces are polished readily available. Both systems are optito a 60-40 cosmetic quality and mized specifically for f/10 Schmidtcoated with a hard broadband coating Cassegrains by Meade and Celestron, and for maximum transmission and durability. feature the same build quality, polish level No finer telecompressor is available. and hard, broadband coatings of the new The newest addition to the NextGEN Ultra WideField 0.7XL. line is the Ultra WideField 0.7XL. This teleOptec is a designing and manufacturing compressor was designed specifically for sysfirm specializing in electro-optical products tems with well corrected optics and flat fields used in astronomy, atmospheric science and such as those obtained from apochromatic microscopy. For more information please refractors. The speed of an f/8 Apo is visit www.optecinc.com. increased to f/5.6 while the optics remain Astronomy TECHNOLOGY TODAY
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NEWPRODUCTS
ADIRONDACK ASTRONOMY
STARLIGHT INSTRUMENTS
Offers Astrovid Voyager X High Res and Low Cost CCD Camera tary, lunar, and solar imaging. The Adirondack Astronomy continues to Voyager X is the perfect camera to move be a leader in supplying astro-imaging up to from webcam imaging. You will technology and the technical know-how immediately see a great improvement in to go with it. They prove this again with all of your images. Even better, everythe Astrovid Voyager X, a high quality, thing you have learned in webcam imaglow noise Astronomical CCD Imaging ing can be applied to imaging with the System with a Voyager X. The Voyager X is a 1/3-inch 1024 x 768 XGA monochrome CCD with noise levels so low that you will see more detail than ever before in your planetary, lunar and solar images. Detail that was lost in noise when using webcams is now visible. Fainter and finer features are more visible. There is also more dynamic range available for both viewing and image processing. This increase in dynamic range allows XGA monosubtle variations to be seen. This means chrome CCD and a USB2.0 interface. that lunar features, such as the lunar The USB2.0 connection is a very low maria, will reveal even the most subtle noise and convenient interface, which tonal changes. This will allow you to see does not require a separate power supply. more fine detail than ever before. Solar All power to drive the camera comes prominences will show more tonal variafrom the USB2.0 port itself. The high tions also resulting in finer detail. speed, low noise XGA camera is perfect Planetary images will also show more for high resolution imaging. detail. The Voyager X is an easy to use sysThe Voyager X is only $695. For tem. Coupled with Registax 4.0, the more information, please visit Voyager X is a premier system for planewww.astrovid.com.
Feather Touch Now Adapted to Orion's SkyQuest Dobsonians
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Astronomy TECHNOLOGY TODAY
The new Starlight Instruments OSQ1 adapter facilitates attachment of the premium Feather Touch Focuser to the Orion Sky Quest XT8, XT10 and XT12 Dobsonians. The adapter fits into the existing base and attaches with three screws. It also comes with three leveling screws (not shown) that will allow precise optical collimation. With the adapter, installation of a Feather Touch Focuser becomes simple; just slip the focuser into the adapter and tighten with two set screws. Because the Feather Touch Focuser is easily interchangeable to other telescopes, you investment retains its value even if you subsequently change telescopes. Simply transfer the focuser from your old telescope to your new one. The OSQ-1 adapter will accept any of Starlight Instruments 2-inch Feather Touch Focusers and is available for only $39.50. For more information, visit www.starlightinstruments.com.
NEWPRODUCTS
MAXFACTORY
Great Red Spot
Master AutoStar Training Software capabilities of the Meade Autostar handbox using what Maxfactory calls “advanced scenario-based guided simulation,” allowing you to quickly and easily gain experience using your Autostar before you ever take it outside with your telescope. Maxfactory multi-media guides let you learn at your own pace, safely and conveniently. Even when Mother Nature prevents you from viewing the cosmos, Maxfactory can keep your astronomical interest alive and moving forward. Master Autostar runs on Windows and Macintosh Operating System Platforms.
Maxfactory’s Master AutoStar training software teaches you how to use your Meade AutoStar handbox from the comfort of your own home. The interactive CD-ROM is compatible with Macintosh and PC computers and allows you to learn at your own pace in Training Mode, and then take the wheel in Solo Mode. Master Autostar even keeps track of your keystrokes and evaluates your progress so you'll be an Autostar pro in no time. You will discover the full range of
Minimum PC Requirements include: • Pentium III computer with 256MB MB+RAM • Windows XP, WIN 2000 • 32X CD-ROM • Mouse, touch pad, or joy stick • Quicktime 7.x or later (included in CD-ROM) Minimum Macintosh Requirements: • Mac OSX • 32X CD-ROM
ASTRONOMY PRODUCTS
We’re Now a Full Line Vixen Dealer!
Vixen VMC200L on GPD2 Mount with Starbook-S • Save over $1000! (Limited Time Only)
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For more information on Maxfactory’s Master AutoStar visit www.maxfactory.com. 8 Inch - Only $324! 10 Inch - Only $499*! 12 Inch - Only $799! *Free Shipping on 10 Inch Model for a Limited Time!
APM refractors/Intes Micro Makustovs/Giro mounts
www.tetontelescope.com
Includes: 2 in. Format Crayford Style Dual-Speed Focuser, 2 in.-1.25 in. Eyepiece Adapter, 32mm 2 in. Format Wide Field and 1.25 in. 9mm Plossl Eyepieces, Zhumell 1.25 in. Laser Collimator, 5 in. muffin fan with power source! These extras alone are worth over $200 if purchased separately!
www.greatredspot.com Astronomy TECHNOLOGY TODAY
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NEWPRODUCTS
ASTROHUTECH Parabolic & Spherical optics Elliptical Diagonal Flats Complete interferometric data 27 years (full-time) experience
www.ostahowskioptics.com fineoptics@dishmail.net 951-763-5959
Astro Sky Telescopes & Piers
Precision Truss Dobsonian Telescopes and Piers Built by James Grigar
www.astrosky.homestead.com/Astrosky.html
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Astronomy TECHNOLOGY TODAY
Introduces New Borg Astrographs One of the fundamental cornerstones of Borg telescope design has been excellence in performance. Astrographs with high-performance objectives combined with uniquely high-performance flattener/reducer elements, are specially designed for imaging as seen in Borg’s unique new 6-element optical systems. The latest in this line of astrographs is a family of three telescopes that are optimized for full-frame digital imaging: the Borg 77EDIIF4.3, 101EDF4.1, and 125SDF3.9. These astrographs utilize the new Borg 4-element ED super reducer, which is optimized for digital imagers, yet covers a full 35mm sized frame. All three astrographs also include built-in filter holders, as well
as a camera rotator for flexible image composition. Borg helical focusers are standard, but motorizable Feather Touch focusers are available as an option. The unique modular design of these Borg astrographs allows easy, cost effective system reconfiguration and facilitate quick disassembly for travel. Please visit www.astrohutech.com for complete information on these and other Astro Hutech astrophotography optimized products.
NEWPRODUCTS
CNC SUPPLY
UNIHEDRON
Offers 2-inch Prime Focus Adapter for Canon EOS DSLR Cameras
Sky Quality Meter Measures Night Sky Brightness The affordable Sky Quality Meter by The Sky Quality Meter permits users to: Unihedron does exactly what its name • Find out how good the night or site really is. implies: it allows the user to measure the • Compare the sky brightness at different brightness of the night sky sites quantitatively. in magnitudes per square • Document the evolution of arcsecond and provides light pollution in your area. unprecedented sensitivity in • Set planetarium dome illumination to mimic the a handheld unit. skies people are likely to This nifty device is very experience elsewhere in simple to use. Point the SQM so the city. that sensor/faceplate points toward the • Monitor sky brightness through the zenith; press the red button once and night, night-to-night, and year-to-year. release. Under urban skies, a reading will be • Determine which nights show the greatest displayed almost immediately. Under the promise for finding the 'faintest fuzzies'! very darkest conditions (no moon in the sky, • Calibrate the effect of sky brightness on far from civilization) the SQM may take up qualitative measures such as the Bortle Scale. to a minute to complete its measurement. • Investigate how sky brightness correlates The Sky Quality Meter is powered by a with the solar cycle and month-to-month sunspot activity. single, standard 9-volt battery, which is • CCD users can make a correlation between included with each new unit shipment and the SQM reading and a specific ADC backwhich will power the efficient SQM through ground level. many use cycles. The SQM is packaged in a small, convenient case and measures a mere The meter features: 3.8 inches by 2.4 inches by 1.0 inch, about • Audible signal while measurement is in the size of a small cell phone. Its displays are progress. large and easy to read and its operation sim• Sky brightness displayed in visual magniple and intuitive. tudes per square arcsecond. • Infrared blocking filter restricts measureThe Sky Quality Meter has a fantastiment to visual bandpass. cally large sensitivity range, but is not • Available information includes temperature intended to measure the relative brightness in both Celsius and Fahrenheit. of daylight skies. To insure the relevance of • Precision readings at even the darkest sites. its measurements to visual observations, it • Power-saving features designed in for maxiincorporates a near-infrared blocking filter in mum battery life. front of the sensor, limiting its sensitivity to • Reverse battery protection. visual light only. The SQM's measurements are also, by design, insensitive to the effects The Sky Quality Meter is available at of temperature variations, insuring accurate www.unihedron.com. readings regardless of ambient temperatures.
As the CCD chips in DSLR cameras get larger, it is more important to have an unobstructed light path to prevent vignetting. Canon engineers very wisely put the largest bayonet mount in the industry on the EOS cameras and the manufacturers of high end scopes wisely put a minimum of 2-inch eyepiece ports on them. CNC Supply's True-2 adapter eliminates the bottleneck from between them. T-Rings have been around for decades. Although it may be the traditional standard, it no longer accommodates sensor dimensions offered with modern DSLR cameras such as Canon’s EOS series. True-2 is a true 2-inch prime focus adapter that transfers directly from the EOS bayonet to the 2-inch port with as few wasted photons as is possible, adding as much as 10-mm more clear aperture over legacy T-Ring adapters. The True-2 adapter costs no more than you would spend on a T-Ring and a good quality 2-inch T-adapter. It features an undercut on the barrel to prevent accidents, is fully baffled to reduce internal reflections, and is threaded for 2inch filters. The adapter is CNC machined of aluminum with a black anodized finish. For more information on the $79 True-2, visit www.cncsupplyinc.com.
Astronomy TECHNOLOGY TODAY
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STAR Workshop 2007 Small Telescope Astronomical Research Technology, Science, and Education By Russ Genet
The trio of transportable SchmidtCassegrain equatorial telescopes, go-to telescope control systems, and affordable CCD cameras has revolutionized small telescope science, not to mention astrophotography. These portable systems – thanks to the high quantum efficiency of their CCD cameras – are, from a research point of view, the equivalent of yesteryear’s massive mountaintop telescopes equipped with low efficiency film cameras. Comprehensive robotic surveys are uncovering thousands of new pulsating stars, eclipsing binaries, asteroids, and potential transiting exoplanets every year. What are the periods of these objects? Which of the potential exoplanets are the real things, regularly transiting their parent stars? To answer such questions, each of these newly-discovered objects requires the
dedicated hours, nights, and even weeks of follow-up observations that only modestaperture telescopes can provide. Automation of, and remote access to, smaller telescopes is facilitating observations both locally and remotely, while global robotic networks are being formed to observe objects round-theclock, passing them, as the Earth turns, from one longitudinal location to the next. Low cost alt-az control systems, instrument rotators, and high-quality thindisk mirrors are just now beginning to be incorporated into portable alt-az telescopes with apertures approaching one-meter. Similar to their huge mountaintop alt-az cousins, these new portable alt-az systems can precisely track and de-rotate objects, thus allowing long CCD exposures. Compared to equatorial telescopes of the same aperture, these new alt-az telescopes
are not only lower in cost and more compact, thanks to their vertical/horizontal structural simplifications, but they are truly portable. Although they are never polar aligned, facilitating fast set up, their precision instrument rotators allow long CCD exposures of many of the much fainter objects uncovered by the new surveys, and with recently available off-the-shelf spectrographs, their superior light-gathering power will enhance both time-series and classification spectroscopy. High school and undergraduate students with an interest in engineering and science are, in increasing numbers, joining the ranks of amateur and professional astronomers in developing and utilizing small telescopes for astronomical research. Whether developing new telescopes, instruments or software, or conducting astronomAstronomy TECHNOLOGY TODAY
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STAR WORKSHOP 2007 when schools were out but summer vacations had not started in earnest. The workshop provided a forum where high school and undergraduate students, amateur and professional astronomers, educators, and the commercial designers and manufacturers of small telescopes, could share their ideas in the rapidly expanding areOne of Tom Johnson’s slides of the founding and early days of nas of small telescope engiCelestron. A somewhat younger Tom is on the right, peering neering development, scithrough a large-aperture Celestron Schmidt-Cassegrain entific research, and undertelescope. graduate education. A larger STAR Conference will ical research, students gain invaluable handsbe held next year (2008) June 19-23, again on experience in engineering and science in San Luis Obispo. Readers of Astronomy while, as coauthors of published papers, Technology Today are welcome at this confertheir academic careers are given a boost. ence. See www.STARConference.org for Assuring that students complete a research details. project within the confines of a single semester – including writing, reviewing, and subAstronomy Technology Today mitting a paper for publication – is a chalTom Johnson, the founder of lenging undertaking for educators. The Celestron, opened the workshop’s astronoSmall Telescope Astronomical Research my technology session with a historical (STAR) Workshop not only provided a sketch of how his development of a techforum for instructors to exchange their nique for manufacturing low-cost Schmidt insights and experiences, but to do so with a corrector plates revolutionized the commerrange of students. cial production of small telescopes. Tom’s The STAR Workshop was sponsored by son, Greg Johnson, described his involvethe Research Scholar in Residence Program ment with the development of Celestron’s at California Polytechnic State University computerized go-to capabilities. (Cal Poly), and was held June 22-24 on Cal A significant portion of small-telescope Poly’s campus in San Luis Obispo, astronomical research consists of continuous California. Late June was chosen as a time
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Astronomy TECHNOLOGY TODAY
time-series CCD photometry of pulsating or eclipsing stars, tumbling asteroids, and suspected transiting exoplanets, as well as sputtering matter spiraling onto white dwarfs, distant microlensing events, and fading supernovae. Hundreds or thousands of exposures are taken of the same object, often all night long, night after night – a task which is an obvious candidate for automation. In the early 1980’s, Lou Boyd and I developed robotic telescopes controlled by low-cost PCs, achieving our first fully automatic operation in 1983. Within a few years, the Fairborn Observatory featured a number of Internet-accessible telescopes at a normally unmanned observatory located on Mt. Hopkins in southern Arizona. Our split-ring, friction-drive, 32-inch telescopes were designed from scratch for dedicated robotic photometry. They had no eyepieces. Automated split-ring equatorial telescopes dedicated to photometry have advanced considerably since these early Fairborn Observatory telescopes, thanks very much to the advent of CCD cameras (the Fairborn systems used aperture photometers equipped with photomultiplier tubes). At the workshop, Jerry Foote described the 16-inch telescope at the Vermilion Cliffs Observatory he recently designed and built for his wife, Cindy Foote. This equatorial telescope features friction drives in both axes. A primary mirror made of low expansion substrate and carbon fiber trusses allow exposures to be made all night long without having to stop for focus adjustments. A Paracorr coma corrector, filter wheel, and SBIG ST-7 camera are located at prime focus. Tim Brown described the 20- and 40inch split-ring equatorial telescopes being developed at the Las Combres Observatory (LCO) for their global network. The 20inch utilizes a modified Meade 20-inch Schmidt-Cassegrain optical assembly, while the 40-inch system is configured as a reflecting Ritchey-Chretien (R-C) system. Rather than using two stages of friction drive reduction, the LCO telescopes use high-torque “cartridge” servomotors and a single stage of
STAR WORKSHOP 2007 friction drive. LCO is building 12 of their 20-inch systems and 6 of their 40-inch systems. These telescopes will be used, in LCO’s global network, to provide follow-up observations of objects discovered in robotic surveys. Initial concentration will be on near-earth asteroids. Automation requires carefully devised procedures, software, and equipment. Jerry Foote, in a one-hour overview, spelled out the basics of automated photometry. Jerry Horne overviewed the software available for automation, such as Doug George’s Maxim DL and Bob Denny’s DC3 scheduler and observatory controller. As Schmidt Cassegrain telescopes become larger, their portability falls off while their prices rise rather sharply. After 20 or so inches of aperture, thin-mirror reflectors with R-C figures or paraboloids with corrective optics near the focal plane begin to dominate “small” science telescopes. Parabolic mirrors, which are significantly less expensive than R-C mirrors, can be used with correctors such as Tele Vue’s 2-inch
Paracorr or the 3- and 4inch Keller Wynn correctors to provide wide, undistorted fields. David Rowe described a corrected Dall Kirkham (CDK) optical system he developed that utilizes a prolate ellipsoid primary, a spherical secondary, and two spherical corrector lenses near the focal plane. Being spherical, the secondary mirror is relatively insensi- Workshop participant Tom Smith stands beside Tom Mathis tive to misalignment. This and the Plane Wave Instruments 20-inch optical assembly on combination provides a Mathis fork mount. Dave Rowe gave a talk at the workshop crisp, undistorted images on his development of the corrected Dall Kirkham (CDK) across a 2-inch diameter optics. Photo taken by Russ Genet at RTMC a few weeks field, fully supporting the before the workshop. optics that employed a lightweight, cellular latest large-format CCD cameras. Utilizing mirror blank. They plan on installing these David’s optical design, Plane Wave optics in a folded, portable, alt-az CDK Instruments is manufacturing 20-inch CDK telescope. optical tube assemblies that employ carbon The emerging class of portable alt-az fiber trusses. David and several of his friends telescopes requires constantly changing ground and figured a set of 42-inch CDK
1200GTO-German Equatorial Mount With the advent of the CCD camera, amateurs are exploring the skies to an ever increasing level of precision, easily exceeding the image quality of large observatories using film techniques decades ago. This new level puts a higher demand on the precision of the equatorial mounting. Many of the finest imagers today have been using our GTO mounts as a solid platform for a wide variety of instruments. The largest of these is our 1200GTO. Since its introduction in 1998, the 1200GTO has gained a reputation for both tracking and pointing accuracy, essential to casual visual observation as well as advanced imaging. Quite a few 1200GTO and 900GTO (smaller cousin) mounts can be found at Mount Pinos in California, favorite observing site of many advanced photographers and imagers. Visit the Cool Sites and Gallery sections of our web site at www.astro-physics.com to see photos of the mount in action and images taken while using the 1200GTO. These mounts are truly a marvel of engineering - maximum strength and rigidity with minimum weight. Our CNC lathes and mills carve out the excess material in both axes of the 1200 and 900 German Equatorials while retaining a heavily ribbed structure for internal strength and rigidity. A unique dovetail was machined into the mating surfaces of the R.A. and Dec axes. This feature allows quick and easy assembly in the field without any tools. The 1200 equatorial is equally at home in a permanent observatory or as a portable mounting for remote star parties thanks to the ease with which the two axes come apart. You CAN have it all. This is the perfect mount for a large refractor, Newtonian, Cassegrain or astrograph. Telescopes commonly used include Astro-Physics 155-206mm refractors, 12-14" SchmidtCassegrains and 10-16" Ritchey-Chretiens and other instruments of similar size. Our customers have been our greatest promoters through the years. Look for them at your next star party, or go to our website to read customer comments we have gathered and check out photos of various scopes on the 1200GTO.
Available for Fall 2007 Delivery
www.astro-physics.com • 815-282-1513 Astronomy TECHNOLOGY TODAY
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STAR WORKSHOP 2007
The complete Sidereal Technology telescope control system was engineered and tested by amateur astronomers, for amateur astronomers. The full control system includes one or two Dual Servo Telescope Controllers, two or four servo motors (Alt/Dec, Az/RtAsc, Focuser, Rotator), and an FCC approved wireless handpad transmitter, with receiver complete with a built in auto-guider port. In addition, Sidereal Technology manufactures and sells “Dob” kits for easy control system installation. This system allows one to navigate the skies with amazing precision and ease with any ASCOM compliant planetarium software. There are over 100 installations of the Sidereal drive rates and instrument rotation and, consequently, a sophisticated control system running complex software. Therefore, special attention was given in this work shop to alt-az control. A short historical diversion is in order here. My involvement with microcomputer control systems began with the robotic telescopes at the Fairborn Observatory in the early 1980’s. I coauthored a book with Mark
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Astronomy TECHNOLOGY TODAY
Technology Dual Servo Telescope Controller. It is a fully developed, easy to use system. The Sidereal Technology Dual Servo Controller is economical, very small, and packed with many features. It connects to two D.C. servo motors with integral encoders, and to two high resolution telescope encoders. It will track and/or guide your telescope without any computer connected, or provide tracking, guiding, Go-To, etc. when connected to either a computer or an Argo Navis. The system is compatible with equatorial, German Equatorial, or alt/az mounts. It is versatile and easy to install on scopes of all sizes. Trueblood, Microcomputer Control of Telescopes, published by Willmann-Bell in 1985, that gave a complete set of equations for alt-az telescope control. (A revised version, The Telescope Control Handbook, was published in 1997 and is still in print). In 1994, Mel Bartels’ article, “How to Build a Simple Computerized Altazimuth Drive System” appeared in Observatory Techniques, inspiring a number of other amateurs, such
as Rusty Fletcher and Chuck Shaw, to build portable, computer-controlled alt-az telescopes. Mel supplied software and populated boards for stepper control systems from his BB AstroDesigns.com and was also working on a servo system. Dan Gray started a new company, Sidereal Technology, and designed, fabricated, and programmed a new D.C. servo telescope controller. Mell Bartels now sells these, along with his telescope control software. At the workshop, Dan described and demonstrated SiTech’s low cost (around $1,000) four-channel servo system (altitude, azimuth, instrument rotation, and focus) that controls a complete alt-az telescope. Fully ASCOM compliant, it can operate stand alone via a wireless (RF) control paddle, or under the control of Sky Commander, Argo-Navis, or laptop computer via popular planetarium/telescope control software such as Maxim DL, The Sky, etc. Dan also described his 14-inch altaz telescope and its instrument rotator, and the recently completed computer-controlled 28-inch alt-az telescopes he and Howard Banich built using mirrors from Mike Lockwood and Kennedy Optics, respectively. I saw both of these telescopes a couple of weeks before the STAR workshop at an impromptu one-day meeting on portable alt-az telescopes at Dan’s shop in Portland. This meeting was also attended by Mel Bartels, Howard Banich, and Richard Berry. The development of an emerging class of portable, computer controlled, general purpose, alt-az telescopes was discussed at the workshop and in depth immediately thereafter. Plans are being formulated for a 20-inch technology demonstration system that will feature Sidereal Technology’s control system, servos and encoders in both axes, focus control, and an instrument rotator at the Newtonian focus. Truss tubes will be carbon fiber, and every effort will be taken to make the system unusually stiff, lightweight, and resistant to wind gusts. We envision this type of telescope being used for both teaching (visual, astrophotography, photometry, and spectroscopy) and research,
STAR WORKSHOP 2007
Starlight Instruments, Inc. Feather Touch® Focuser Quality Focusers and Accessories for the Amateur Astronomer
2" focusers available for: Newtonians, Refractors, Schmidt-Cass Micros available for: Celestrons, Meades, Takahashi, Tele Vue Pictured Top: Russ Genet, Howard Banich, Richard Berry, Mel Bartels, Dan Gray, pose by Dan’s 14-inch alt-az telescope at the one-day pre-workshop Portland alt-az meeting. The instrument rotator is on the other side of the telescope. Pictured Left: Howard brought his 28-inch telescope to a one-day, pre-workshop meeting in the back end of his SUV. The portability of this large-aperture telescope is amazing. The f/3.6 primary mirror was made by Kennedy Optics. Pictured Below: Howard Banich and Russ Genet stand beside Howard’s portable 28-inch alt-az telescope, which uses a Sidereal Technology control system.
Ultra-smooth coarse/fine focus knobs (10:1 Ratio) Durable hardened stainless steel and anodized aluminum construction Machined internal knife edged baffling Draw tube available with nylon tipped thumb screws (gentle on eyepieces) or locking brass compression ring Ultra-Low backlash system for accurate control Sleek aesthetic design LIMITED LIFETIME WARRANTY!
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www.starlightinstruments.com Astronomy TECHNOLOGY TODAY
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STAR WORKSHOP 2007 including semi-automated, all night, time-series photometry. Emphasis will be placed on ease of setup and use, reliability, and transportability. Larger-aperture versions would employ a folded optical scheme such as the 42-inch CDK system described by David Rowe at the Workshop.
Today, telescope construction is funded by national budgets and instruments are launched into space to get clearer views of celestial objects. Is it still possible for amateur astronomers to contribute to astronomical science? Yes, indeed! Some research projects require the small telescope’s flexability in observing schedule, and familiarity with the night sky that are attributes of the advanced amateur astronomer. These projects provide results that are valuable to the astronomical community, and publishable contributions to the professional literature. Meteor studies, occultations, CCD photometry and astrometry, searches for novae, supernovae and lunar meteor impacts are all being successfully pursued by amateur astronomers. Robert Bucheim’s The Sky is Your Laboratory: Advanced Astronomy Projects for Amateurs describes 18 research areas including their value, the observational and data reduction procedures, and venues for publication of your results. It can transform you from a backyard stargazer to an amateur scientist.
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Astronomy TECHNOLOGY TODAY
Small Telescope Jo Johnson, Russ Genet, and Darrell Grisham work through Science calculations for the separation and position angles of visual Small telescope scidouble stars for presentations given by Jo and Darrell at the ence enjoys a rich, four workshop. centuries long tradition teur, student, and professional astronomers that will be celebrated at the upcoming conin many research areas. ference, Galileo’s Legacy: Small Telescope Darrell Grisham and Jo Johnson, both Science 1609 and 2009. New Year’s Eve firestudents of mine at Cuesta College, presentworks and a five-day Hawaiian conference, ed, in their first-ever scientific talks, the 1-5 January 2009, will assess the state of results of their visual observations of the sepsmall telescopes and the remarkable science aration and position angles of double stars, they are producing, while also honoring soon to be published as papers in the Journal Galileo who initiated the tradition of of Double Star Observations. Both used making fine small telescopes and using them to advance scientific knowledge. Readers of Astronomy Technology Today would be most welcome to attend and speak at the many special focus sessions – see www.GalileosLegacy.org for details. Research projects suitable for small telescopes abound. They include: the separation and position angles of visual double stars; asteroid and comet positions; searches for asteroids, comets, nova, and supernova; photometric variations over time of asteroids, intrinsically variable stars, cataclysmic variables, eclipsing binaries, exoplanet transits, and microlensing events; high speed photometry of asteroid and lunar occultations; and, with the larger of the “small” telescopes, spectroscopy time series variability and classification. These many possibilities and more are covered in Robert Buchheim’s Greg Johnson looks on as Walt Morgan recently released book, The Sky is Your sets up to observe lunar occultations. Laboratory: Advanced Astronomy Projects for Walt’s system includes a GPS receiver, a Amateurs. At the workshop, Robert kindly “Kiwi box” time stamp inserter, and a provided an overview of small-telescope scicamcorder as well as an 8-inch Meade ence, followed by presentations from amaLX-200 telescope.
STAR WORKSHOP 2007 Meade laser-etched astrometric eyepieces. Darrell, with a truly small telescope – a 3inch, manually operated vintage Tasco refractor mounted on a 6-inch diameter steel pier embedded in a ton of concrete – has achieved amazing precision. Jo built his own position angle indicator, making his observations with a 12-inch Meade LX-200 telescope at my Orion Observatory. Walter Morgan and Kent Okasaki, both long-time members of the International Occultation and Timing Association (IOTA), described their experiences with both lunar and asteroid occultations. Walter brought his 8-inch Meade LX-200 telescope, GPS receiver, Kiwi time inserter, and cam-recorder to the workshop’s evening “star-b-que” at the Orion Observatory. He recorded several lunar occultations which he dutifully analyzed and presented at the workshop the following day. My Cuesta College research seminar students are looking forward to observing lunar occultations this fall, and also hope to form a “line” of telescopes to observe an asteroid occultation to help determine its size and shape. Cindy Foote, an amateur astronomer for just two years – with her own 16-inch, research-grade, semi-automatic telescope situated at a very dark site – gave her first-ever science talk at the workshop. Cindy struck pay dirt as the co-discoverer of two transiting exoplanets with the Vermillion Cliffs
Cindy Foote’s 16-inch telescope at Vermillion Cliffs Observatory. Her CCD camera is mounted at prime focus. The telescope’s truss is made of carbon fiber tubes.
Light curve showing the dimming that occurred when the planet XO-1b passed in front of its parent star XO-1. The team has since discovered XO-2b and XO-3b that were announced at AAS in May.
Observatory’s 24-inch telescope, which she overview of pulsating stars. Similar to was using while Jerry Foote built her 16Cepheid variables, determination of the pulinch telescope. As a member of Peter sation period of RR Lyrae stars provides an McCullough’s research group, she and severestimate of their luminosity and hence disal other amateur astronomers checked out tance. A joint Cal Poly/Cuesta College stupotential transits from candidates generated dent RR Lyrae observing program is being by an array of 4-inch robotic telescopes planned for this fall. located at Haleakala on Maui. For both of Cuesta College research seminar stuthese discoveries, Cindy was the first memdent Brittany McCrigler reported her obserber of the team to detect the transits. Their vations of a pulsating star that she observed results will be published shortly in the at Orion Observatory with other students Astrophysics Journal. this past spring. This star had been identiJohn Keller, who teaches astronomy at fied, in the MOTESS/GNAT survey of a Cal Poly, gave an overview of asteroids. John, a recent graduate in Planetary Sciences from the University of Arizona, is looking forward to working with Cal Poly and Cuesta students to make astrometric determinations of asteroid positions and to also obtain asteroid light curves with Cal Poly’s 12-inch Meade LX-200 telescope and new SBIG CCD camera. Cuesta College students Brittany McCrigler and Jolon Michelle Ouellette, Johnson at the workshop dinner. They gave their first ever who also teaches astronomy science talks at the conference, and both have papers at Cal Poly, provided an nearing completion.
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STAR WORKSHOP 2007
Shown is the Martin Solar Polar Telescope at Helio Research. The optical bench is parallel with the Earth’s axis of rotation. The Telescope tracks the Sun only by rotation of the optical bench around its long axis. The circular primary mirror appears as an oval-shaped mirror in the upper end of the telescope. Sunlight is reflected from the mirror through a 10-inch lens in the tube at the upper end. The solar disk is brought to prime focus at the upper end of the small tubes after passing through two dichroic mirrors to eliminate heat by restricting the part of the spectrum observed to red sunlight. A field aperture at prime focus limits the area of Sun to be photographed to 10x10 arc minutes. The solar image is then relayed by secondary lenses through a 1 Angstrom prefilter and a 1/10 Angstrom narrow-band filter to come to focus on a 1024x1024 CCD array in an Apogee 6 camera. A small guidescope maintains the pointing at a chosen location on the Sun. The electronics cabinet is shown near the lower end of the telescope. Once a target on the Sun is selected, images are automatically recorded on a large data disc in a computer (not shown) which also allows one to visually see the subject being recorded.
Our piers offer superior rigidity to virtually cancel out any accidental vibration. We manufacture piers for Meade and Celestron telescopes, Mitty Evolution wedges, Paramount ME and Losmandy mounts. We can also custom fabricate your pier on our state of the art laser machines.
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Astronomy TECHNOLOGY TODAY
strip of sky near the celestial equator, as a likely short-term variable. Brittany used MPO Canopus along with the Peranso analysis program to determine the star’s pulsation period. She plans on majoring in astrophysics at the University of California, Berkeley. Finally, Sara Martin, a professional solar astronomer at Helio Research, described the Martin Solar Polar Telescope designed and built by her husband, Douglas Martin. After taking early retirement from Caltech and the Big Bear Solar Observatory, Sara and Douglas, together with colleagues, established the nonprofit Helio Research Corporation for research and education in the astronomical sciences. The Helio
Research laboratory for data analysis and the Martin Solar Telescope are located at their residence in La Crescenta, California, which has proven to be a good site for solar observing. With funding from research grants, Sara and Helio Research employees (including students) use special filters for recording the Doppler shifts of activated filaments, erupting prominences, solar flares and other dynamic features on the Sun. In practice, the observations are taken by tuning each of two filters to different wavelengths around the Hydrogen alpha line in the solar spectrum. The first is a 1A prefilter that tunes mechanically under computer control of a motor that tilts it in steps of a fraction of a
STAR WORKSHOP 2007
Star-b-que at the Orion Observatory. In the background are permanently-mounted 12- and 10-inch Meade LX-200 telescopes. In the foreground is Tom Frey’s 18-inch Obsession he brought for the evening’s star party. Orion Observatory and Sidereal Technology co-sponsored the Star-b-que.
degree. The second narrow-band filter is a special Fabry-Perot etalon that changes wavelength when high voltage is applied across the surfaces of a very flat, thin crystal of lithium niobate. A good observing day consists of automated images typically recorded at 5 second intervals for periods of 5 or more hours. Measurements are made from “movies” of changing solar events, and research results are presented at professional meetings and published in conference proceedings and journals. Sara discussed several research projects on solar filament evolution and eruption which involved students in nearly all phases of the research. Undergraduate Engineering and Science Education Small telescope engineering development is particularly well suited to high school and undergraduate students. By designing and developing telescopes and robotic observatories, engineering students can hone their skills as they provide their schools with cutting-edge scientific research facilities. Small telescopes science is also well suit-
ed to high school and undergraduate students and can be properly supported by telescopes and instruments that are affordable and useful in many areas of research. In one or two-semester research courses and summer camps, students have proven their ability to conduct high-quality, published research. Through hands-on research, these students develop an appreciation for the true exploratory nature of science. I have been associated with student research since 1980, when Douglas Hall and I founded the IAPPP, an international society devoted to astronomical photometry. A number of years ago, while teaching astronomy at Central Arizona College, I initiated my first one-semester undergraduate astronomical research seminar. Using a robotic telescope at the Fairborn Observatory, students observed a number of Cepheid variables, determined their periods, and reported their results at a meeting of the American Astronomical Society. My firm requirement for this and my subsequent research seminars has been that students – either singly or in small teams – plan, conduct, and complete a research project by the end of the semester. Their projects must include the
review and submission of a paper to an astronomical journal or, alternatively, they can submit an abstract for a poster or talk they give in person at an astronomical conference. Besides holding research seminars, I have enjoyed sponsoring senior projects at Cal Poly where, over a more generous two semesters, students (singly) plan, conduct, and report on their projects in published papers or as talks or posters at formal conferences. The STAR Workshop featured an “educational roundtable” discussion of last fall’s research seminar at Cuesta College. Students had obtained time-series CCD photometry of nine MOTESS/GNAT survey stars, found two to be continuously variable and had determined their periods. They had written and submitted a paper to the refereed Journal of the American Association of Variable Star Observers, as well as published abstracts/poster presentations at the American Astronomical Society and the Society for Astronomical Science. Student travel was funded by a local retired physicist, George Alers. The students had received awards, and had been featured in local newspaper articles and television news programs. After last fall’s research seminar a number of actions were taken to improve the upcoming fall seminar. These were discussed during the roundtable discussions. Student participation is being increased to include a team of advanced-placement physics students from Arroyo Grande High School advised by their physics instructor, John Baxter. A number of amateur astronomers from the Central Coast Astronomical Society were enlisted as both students and mentors. A spring astronomy research starb-que and star party was held to bring the seminar’s participants together well before the first class. Not willing to wait until fall, a number of students began their research, informally, in the spring, nearly completing three projects by the June workshop. The greatest difficulty with last fall’s research seminar was the need to operate within the confines of a single semester. The students had to obtain many thousands of
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STAR WORKSHOP 2007 participants kindly agreed to provide student-requested observations this fall, and three described their observatories at the workshop. Tom Smith, a key mentor in last fall’s seminar, will be supplying observations from Dark Ridge Observatory’s (DRO’s) new home at 7,200-feet elevation in New Mexico. DRO will, shortly, be installing its 20-inch alt-az and two Meade 14-inch LX-200 GPS telescopes on permanent piers. Jim Carlisle will be working Tom Smith standing beside his Meade 14-inch LX-200 with students at his Hill House GPS telescope equipped with an SBIG ST-7 camera at Observatory in Atascadero. His its new Dark Ridge Observatory at 7,200 feet in New 14-inch Meade RCX-400 teleMexico. scope and SBIG ST402 camera time-series photometric observations over will be utilized for time series photometry of dozens of nights, and learn how to and actuasteroids and variable stars. ally reduce this mountain of data. In addiTom Frey, who teaches chemistry at Cal tion, the students had to analyze and write Poly, will be making visual observations with up their results and send them off for outside his 18-inch Obsession telescope. Tom review. Although they were successful, and purchased an astrometric eyepiece and submitted their final paper on the last day of devised a position angle readout for class, it was a strain on both these students, their hard-working mentor, Tom Smith, and on me – their instructor and observatory director. The roundtable discussion suggested two solutions to reduce the workload for students, mentors, and instructor. First, a larger variety of research projects should be encouraged, including ones that would be less time consuming. Students should only tackle advanced projects after they had gained experience with a more basic project and are assured of published results. Second, a number of observatories, both local and remote, should be asked to provide reduced observations. Students would request the observations in an appropriate format, and would analyze and publish the results, including the observer as a co-author in their paper. While not making the obserTom Frey assembles his 18-inch vations themselves, students would be Obsession at the workshop star-b-que. expected to understand how the observations Tom is measuring the separation and were made and reduced. Several workshop position angles of visual binary stars.
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observing double stars. Finally, telescope development and construction projects suitable for one-semester seminars and full-year senior projects were discussed after the workshop. The design and construction of a “junior” version of the proposed 20-inch alt-az technical demonstration telescope may be an appropriate student undertaking. Small Telescope Development and Research Today Small telescope development is entering an exciting new era. With the emerging development of portable computer-controlled alt-az telescopes with instrument rotators and thin but high-quality mirrors, “small” is being extended to 32 and perhaps, eventually, 40-inches. Spectroscopy here we come! Small has come a long ways since Galileo’s 1.5-inch telescope! Small telescope research has never been better positioned or more in demand. The conjunction of highly capable telescopes, and the overwhelming outpouring of new objects to research from the automated, big-telescope surveys, bodes well for the future of small telescope research. Not only can backyard amateur astronomers help meet this urgent need for scientific observations, but so can undergraduate and even high school students, aided not only by local amateur astronomy mentors, but by observations provided from remote amateur observatories. The advancement of smaller telescopes and their application to scientific research is enhanced by a technical understanding not only of available telescopes, instruments, and various accessories, but a feel for where small telescope technology is heading. Astronomy Technology Today provides a valuable forum for technical information exchange. It is my hope that many of the readers of this article will become sufficiently intrigued with small telescope engineering development and scientific research to attend next years STAR Conference. You can register now at www.STARConference.org. Feel free to email me with any questions at russmgenet@aol.com.
Integrating Video Cameras
Everyone knows that when you are planning to spend a lot of money, it really pays off to examine your needs or interests and spend wisely. Astronomical imaging is, of course, no exception, so here is some information that may help you to make that all important examination. by Owen Sage
First a few words about the basics - what is this thing called a “CCD” anyway? It will surprise no one to learn that modern astronomical imaging involves using electronic detectors of one sort or another. The solid state Charge Coupled Device (CCD) is, perhaps, the most popular of these new detectors and in professional and amateur imaging, the CCD reigns pretty much supreme for its efficiency and versatility. The CCD's array of picture elements (pixels) is better than most other detection technologies at getting a signal out (electrons) for the data in (photons). The CCD is much more effective than photographic emulsions, which is why it has replaced film photography for astronomical imaging. When this CCD detector is coupled with different sorts of electronics it can make images that are output in several different ways. This article will touch on a couple of them and then look at the most esoteric in more detail. Where are these CCDs used? When the subject of CCD cameras comes up in amateur astronomy circles, most folks think of the long exposure cam-
eras available from Santa Barbara Instrument Group (SBIG), Apogee, Celestron, Orion Telescopes, or Meade, etc. These cameras take long exposure images of deep sky objects, download them into a computer, and, with some clever post processing, can produce stunning images. Also, in the last few years, a lot of excellent work has been done using modified webcams. The principle is the same for either webcam or dedicated imager because you need a computer or the equivalent to operate them, receive the data, and then
CCD Array
Analog Video
process the resulting image. The longer exposures also pretty well require you to use an equatorially mounted telescope or a ‘de-rotator’ on an Alt-Az scope to compensate for image rotation. Another sort of CCD camera that is popular with amateur astronomy folks is the sensitive pure analog video camera such as the KT&C 350BH or the Watec 902 series. These cameras are simply video cameras with extremely sensitive CCDs and they are made for the security industry. The good time resolution of the 30 frame per
A to D converter
DSP
D to A Analog converter Video
Memory
This block diagram of an IVC shows the Analog to Digital converter, the Digital Signal Processor, and Digital to Analog converter. Astronomy TECHNOLOGY TODAY
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INTEGRATING VIDEO CAMERAS on the pixel array of the CCD like the long exposure CCD cameras, but then can be displayed in real time video for viewing on ordinary TV monitors just like a regular video camera. These cameras often have very large adjustment ranges for shutter speed or exposure length, video gain, back lighting, etc., and make for very versatile imagers. The chief limitation of an IVC is the Modified IVC on a Questar. A sensitive analog video size and resolution of camera is next to the base. the CCD itself and second video rate is excellent for occultathey are not usually cooled to reduce noise. tions, etc., but the short exposure time of The CCD in an IVC is almost always each frame limits their magnitude grasp. ‘video’ sized, which are smaller, physically On the other hand, the good time resoluand in resolution, than many dedicated tion creates an excellent record of exactly imagers. A typical but simplified IVC what happened and, by including a time block diagram is seen on the previous page. signal onto each video frame, exactly when The CCD array collects the light it happened. Also by taking the analog sigwhich is digitized by the Analog to Digital nal from one of these cameras, digitizing it Converter (ADC), either physically inside and recording the digital data in a computthe Digital Signal Processor (DSP) or on a er, you can do more with it. You can take separate chip. The DSP is a microcomputthe digitized video frames and stack them er like the ones in personal computers, but together in the computer's memory and optimized for rapidly processing signal improve the sensitivity and signal to noise data. This is why the IVC doesn't need an ratio to a degree. This technique can yield external PC to control it – it has its own excellent pictures of brighter objects such computer built right in. After digitizing the as Luna or the brighter planets. image data the DSP tucks it into the IVC's But there is a third kind of CCD camonboard memory for further processing era that is a hybrid of the above two: the according to the settings chosen by the integrating video camera (IVC). user. The DSP churns away doing the actuIntegrating video cameras can be set to take al image processing with the digital image time exposures that are longer than a data in memory. The processed image straight video camera, but generally shorter winds up in another part of the memory than a dedicated CCD camera. The accuand then is fetched by the DSP and output mulated image is stored inside the camera, by means of the Digital to Analog processed there, and then output as a stanConverter (DAC). The result is analog data dard video stream ready to be viewed with like that produced by a normal analog a monitor - no computer required. The key video camera and can be viewed immedito recognizing these imagers is that they are ately and/or recorded using regular video self contained - either just the camera itself equipment. The DSP is a rather busy chip or a camera head with a small control box as it is digitizing, saving, processing, fetchattached to it. ing, and outputting all at the same time. The IVC’s trick of time exposures Most IVCs start life as security camallows images to be accumulated directly eras and are made by established manufac-
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turers such as Mintron in Taiwan and Watec in Japan. These platforms provide the framework for such camera systems as the Adirondack Astronomy’s StellaCams and are specifically modified for those astronomy applications. Since the IVC (either self contained or just the camera head) is relatively small, it fits even fairly small scopes with little trouble. In the simplest use, the IVC can operate as a regular video camera and show images that move and are dynamic, such as eclipses or occultations. The video out is displayed and/or recorded just like regular video because it is. This video capability also allows for checking the star field and the very nice feature of quick focusing. For general jaw dropping use at a public star party, an IVC on a medium sized telescope feeding a large screen video display is hard to beat. With very short focal length scopes, it will display large areas of the sky and, with relatively short exposures of a couple of seconds, show fantastic views of the Milky Way or Messier objects. Large aperture instruments with longer focal lengths will show the faint fuzzies better than you can see by viewing directly at the telescope eyepiece. When you want to turn serious, the IVC can accommodate that too. With flat fielding, filters and good digitizing software/hardware, the IVC can pretty well hold its own with all but the high end dedicated CCD imagers. Once the data has been captured by the camera, it can be simply displayed for view, but two more steps are necessary to make the best use of it: Digitizing (again) and Post Processing. The digitized intermediate image inside of the IVC is not available to save directly and so to do further processing of that beautiful image, you will have to digitize the image again and save it on a computer. The digitizing of the video output may seem simple, but it is a critical step in the serious use of both the IVC and the sensitive video cameras. This step has some clear choices and some interesting subtleties and will be examined in more detail in a future article as not all digitizing is the same. Taking good images is one half of the
INTEGRATING VIDEO CAMERAS magic of astronomical imaging. Once the image is digitized and in the computer, the other half of the magic can begin - even with cloudy skies. This computer/artist image processing magic is an entire subject in itself and totally beyond the scope of these mostly hardware oriented articles. A few comments about a couple of the most popular manufacturer’s IVCs The 12V1 by Mintron of Tiawan is the original basis for the Adirondack Video Astronomy StellaCam EX (www.astrovid.com). The 12V1 and related cameras made by Mintron form a product group generally characterized by the name ‘Starlight’ implying that these cameras, both black and white, and color, can see by starlight. The black and white cameras are more sensitive than the color models due to the nature of color CCD detectors. But, the color models can work surprisingly well as astronomical imagers too, and save the requirement of having to use filters and take multiple exposures as with the black and white cameras. The 12V1 is a good black and white camera, with lots of flexibility and, if desired, can be easily modified for remote and/or computer control. It is completely self contained in a metal box about the size and weight of a large eyepiece. The modified IVC pictured on the previous page started out life as a 12V1, so is a good example of typical size. The Starlight IVCs that Mintron makes have their adjustments available as viewable ‘on-screen’ menus that overlay the image video. While they are displayed you can clearly see what is available and make adjustments by pushing buttons to get what you want. When you are done you simply dismiss the menu and then can see the image video with no overlay. Since the menu structure is ‘on-screen,’ the settings used when recording an image are clearly seen and can be recorded as notes on exactly what settings you choose for a particular image. The 12V1 has a very sensitive ‘Type 1/2’ Ex-view HAD CCD, which gives it a
leg up at any particular shutter speed or exposure time over a regular sensitive HAD CCD. The Ex-view HAD CCD here is the same general type that is used in sensitive straight video cameras and it has tiny little lenses in front of each pixel on the actual CCD array to make sure that as much light as possible goes directly to the detectors. The Ex-view CCD is also a bit delicate and pixels will fail as time goes by, resulting in several so called 'hot pixels' that usually show white. These hot pixels are always there and can be mistaken for stars. They are not much of a problem when viewing a star field on a monitor as they do look like stars. When you are working on an image with a computer they can be removed as well, so they are not much of a problem in either case. This CCD is followed by a proprietary computer chip (the DSP) designed and made by Mintron. As shown in the Image 1 block diagram, this DSP digitizes the image stream from the CCD and saves it in the camera’s memory. Then, while the DSP is taking another image, it is also outputting the last saved image as a frozen image, but in a continuous video stream so that this image can be viewed continuously on the monitor. The Mintron is limited to 2 second time exposures, but is also capable of fast shutter speeds up to 1/10,000 of a second. The gain and other parameters are adjustable so that you can set up the camera just so and then image away. I had a 12V1 and liked it a lot, then wrecked it accidentally – oh well. One of it’s uses that I miss the most is as an awesome finder. I coupled it to a 6- to 48-mm focal length f/1 (!) zoom lens. At the 6-mm zoom extreme it would show constellation sized areas of the sky. I could then go to warp speed, zoom out to
48 mm while integrating, and at a 2-second exposure it would show 10th- or 11thmagnitude stars. Not bad for this 48-mm virtual telescope! When I went on occultation expeditions I could zoom out to see constellations of familiar stars and then zoom in to match my finder charts. At the chart level zoom I could see enough stars to be sure of the field and my target object on the video monitor. When I had the correct target centered, I would switch video streams from the finder to the data camera mounted on the big telescope and then record the event and watch it on the monitor. The 120N and 120N+ are both good cameras made by Watec of Japan. The 120N is capable of up to 8 second time exposures which, even though it only has a regular sensitivity type 1/2 HAD CCD, gives it an edge over the 12V1 for deep sky imaging. With adjustable gain, gamma, and selectable longer exposures, it is quite controllable. The chief limitation is the lack of shutter speeds faster than 1/60 second. The second limitation is the limit of 8 seconds for long exposures. One nice feature is the use of a non-Ex-view CCD. The regular HAD CCD is better at low noise, and tends to have fewer hot pixels than the Ex-view CCDs, even though they are less sensitive. Watec has fixed the limitations of the older 120N with the 120N+ camera. Now one has the choice of 1/2,000 of a second up to 8 seconds with continuous video output, and longer than 8 seconds with display after exposure (although it appears one can be doing another long, > 8 second, exposure while displaying the last one). As a result of these improvements, these cameras are now encroaching on the performance territory of the traditional long exposure CCD camera. Adirondack Astronomy TECHNOLOGY TODAY
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INTEGRATING VIDEO CAMERAS Astronomy uses these cameras as the basis for the StellaCam II (120N) and StellaCam III(120+), and the latter can be purchased with a thermo electric cooler (TEC). The TEC is a good idea as the 120N+ is capable of exposures long enough to need the reduction in noise offered by running at lower temperatures. OK, what is next? This short article supplies some basic information on the IVC and briefly explains its place in the range of astronomical applications. Naturally, I did not try to cover the entire field, but in the fullness of time and as test items become available, I will report on their use. For historical reasons, the size of video detectors like the size of TV screens has been measured along the diagonal. Some of the old vidicon tubes had a 1/2-inch diagonal photocathode and, even though they were vacuum tubes, were about the smallest available detectors. Modern solid-state detectors are built in a completely different way and, being solid-state, can be much smaller. Production CCDs are now classified into ‘Types’ because the diagonal is given in roughly inch sizes, but do not mention the inch. So, we have Type 1/4, 1/3, 1/2, etc. A note on video names. In the USA and Japan, we use 30 frame per second video and call color video NTSC, while monochromatic video (black and white) is known as EIA. In Europe, and much of the rest of the world, the frame rate is 25 per second and the names are PAL, for color, and CCIR, for B&W. Just accept it as the acronyms in this hardware article are growing too fast to explain every one. Besides, that is what Google is for!
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Astronomy TECHNOLOGY TODAY
VIXEN VC 200L
Two Looks at the Visual and Imaging Perfomance of the VISAC
One Astronomer Takes a Visual Tour While Another Enjoys the Imaging Experience. By Daniel Mounsey and Shawn Hendrix
Daniel Evaluates the VC200L’s Visual Capabilities I was pleased to have the opportunity to report my visual experiences with the Vixen 8-inch VC200L Sixth-Order Aspherical Cassegrain (“VISAC” for short). The VISAC optical system differs significantly from that of the more common Schmidt-Cassegrain Telescope, because it does not rely on a frontal corrector plate. Instead, the VISAC houses a four vane spi-
der supported mount that holds the secondary mirror, while a three element corrector lens resides at the back of the OTA, in front of the focuser. I personally find this optical design to be an advantage because dew formation on
the frontal corrector plate of a typical ply wonderful. It is an independent rack & Schmidt-Cassegrain is a recurring problem. pinion model mounted behind the priIn a way, the VISAC optical tube behaves mary, which remains stationary. Most like a dew shield in itself with its primary Schmidt-Cassegrains suffer from mirror mirror safely tucked at the bottom of the shift, to one degree or another. Companies open optical tube. This design also speeds have done their best to minimize this comup the cooling process compared to stanmon issue, but it is still present in the many dard Schmidt-Cassegrain designs. models I’ve tested. The typical SchmidtWith a focal length of 1800 mm, at Cassegrain is focused by moving the priF/9 the focal ratio is also a bit faster than that of the Vixen VC200L - 8" f/9 Modified Cassegrain OTA typical Schmidt-Cassegrain, Specifications and its central obstruction, Optical Design Catadioptric at 40%, is a little larger. 8" (200mm) Keep in mind though that Aperture Limiting Visual Magnitude 13.3 Mag the VISAC is designed prif/9 marily to serve as an astro Focal Ratio 70.9" (1800mm) imaging system, but many Focal Length observers have been curious Focuser Design* 2" Rack-and-Pinion to learn more about its visu- Weight – OTA 13.2 lbs (6 kg) al performance and that is Tube Length 24.4" (486mm) the focus of my report. Diameter 9.13" (232mm) The focuser with which *(1.25" or T2 adaptations are optional) the VISAC is fitted is simAstronomy TECHNOLOGY TODAY
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VIXEN VC 200L mary optic back and forth, in effect changing the focal length of the optical train to match the location of the imaging sensor or eyepiece focal point, rather than moving those elements to a fixed focal point. This mirror shift can sometimes cause target objects to shift on the focus plane during focus and can be quite troublesome while imaging deep sky objects. Because the VISAC primary stays stationary, mirror shift induced image shift is essentially eliminated. Another interesting feature is the VISAC’s metal side plate which runs along one side of the dovetail plate. This brilliant idea prevents the clamp screws of the saddle plate from marring the dovetail plate and should be incorporated on other designs. Another nice feature is a carrying handle located on top of the OTA. This proved to be very useful when lifting the optical tube on and off the mount. The VISAC is surprisingly light at about 16 pounds including the supplied 7x50mm finder and 1.25-inch star diagonal. Vixen also offers an optional
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Astronomy TECHNOLOGY TODAY
carrying case, and an f/6.4 focal reducer which is highly recommended for imaging. The focuser does accommodate a larger 2-inch star diagonal if desired. I would have preferred that the 2-inch visual back be equipped with a compression ring instead of the older school thumb screws as this would further help prevent possible oscillation of the diagonal. Compression rings tend to secure diagonals a bit more solidly than set screws alone and also help prevent set screw marring of the diagonal barrel. These observations took place on June 19, 2007, from Pasadena, California. Seeing conditions on this evening were about 7 out of 10 and nice enough to conduct some good observations of deep sky objects as well as planets. I started my first observations on Vega in order to check collimation and star test the instrument. The collimation was dead perfect, while the optics exhibited just a bit of under-correction. My first observations started with a Televue 22-mm Panoptic eyepiece. This produced a magnification of 82x, and framed M8, the Lagoon nebula, very nicely. The emission nebula exhibits an ample number of stars for demonstrating the full field performance of the VICAC, and, to my surprise, these were pinpoint from nearly edge to edge and proved to be much tighter than those produced by the Schmidt-Cassegrains I’ve tested in the past. I then slipped in a 2inch star diagonal and my 35-mm Televue Panoptic eyepiece for a magnification of 51x, and, once again, the stars were pin point from nearly edge to edge. One thing that really stood out while focusing the image was the actual focuser itself. The VISAC’s stock focuser is one of the smoothest I’ve ever tested and I really liked it; in fact it felt even nicer than the focuser on my 6-inch Takahashi refractor. Two other observers who were present during this observation agreed that the rack and pinion focuser was exceptional. Jupiter was pretty well placed at this point, so I decided to put in some higher magnification using a Pentax 10-mm XW eyepiece to yield 180x. Although the deep sky images were quite wonderful, the size of the central obstruction was a bit less favorable for teasing out optimum contrast of the features of Jupiter. Jupiter however still
revealed a number of colored belts and enough detail for an interesting and enjoyable view. Although there may be more appropriate choices for planetary observations, it is important to remember that the VISAC was not really designed with planetary work in mind. Next, I decided to have a look at Alberio, the famous colored double in Cygnus. High magnifications with a Pentax 7-mm XW at 257x, revealed two very nice Airy discs surrounded by a few very faint diffraction rings. The red and blue colors of the pair also stood out quite well. Overall, the visual image quality of the VISAC was quite impressive, particularly considering how portable and light weight it is. It is a step up in image quality from the typical Schmidt-Cassegrain in my opinion, particularly with regard to edge sharpness. Although the VISAC costs nearly double what an 8-inch Schmidt-Cassegrain optical tube does, I think it’s worth it! The build quality is very high and collimation options are almost limitless. There are a series of adjustment screws at the back of the optical tube for collimation by adjustment of the primary and focuser orientation can even be adjusted as well.
VIXEN VC 200L Shawn Tries His Hand at Imaging with the VISAC I would like to thank Woodland Hills Telescope for allowing me to test the Vixen VC200L. I was given the telescope with the claim that the Vixen VC200L was designed to produce one of the best astro-imaging instruments available and I set out to prove them right, wrong, or somewhere in between. It would not be fair to test the scope on an inferior mount, so the scope was equipped with a Vixen Sphinx Mount, the same that is paired with the VC200L when purchased as a package. I can sum up my impressions of the mount this way: smooth, solid, and Xbox meets astronomy. The Star Book is a fantastic product and the mount/tripod combination a very well engineered machine. But, that is another review for another time. The VC200L is an excellent visual scope as well as imaging platform. Once cooled and set up properly, the scope delivers sharp, low power images, bright objects with crisp stars, and very good high power images of double stars, carbon stars, and most every other deep sky object I pointed it at. Views of Jupiter were pleasing, but not optimum, due to loss of contrast caused primarily by the effects of the secondary mirror assembly central obstruction. That is the downside of the relatively large 40 per cent obstruction of that assembly. This however is very important to the photographic side. The large secondary allows the Telescope to fully illuminate a 35mm film frame. This is one of the very nice features of its unique catadioptric design. The VC200L is not a SchmidtCassegrain as it may appear upon first inspection. You will quickly notice the lack of a corrector lens on the front of the tube assembly. This is because it uses a sixth order aspherical primary mirror, a convex secondary mirror, and finally a triplet corrector lens. Vixen has assigned the abbreviation VISAC (Vixen Sixth Order Aspherical Cassegrain). I simply call it stunning. The optical train contains a 3-element corrector which corrects for field curvature and coma much better than a Schmidt corrector. This lends to stars as sharp on the edge as they are in the center of the film or
CCD. A nice secondary benefit of the design is that it does not dew up as easily, but you still may want to use a dew shield to protect the secondary from dew. The open tube also cools much faster and cool down is an absolute necessity to image quality. Indeed, the VC200L showed large thermal currents that were very visible in the image until it has fully cooled. Fortunately, this did not take long. Along with proper cool down, perfect collimation is key to obtaining a good star test. Collimation is accomplished by a procedure similar to that used for Newtonians; tilt of the secondary mirror is first adjusted and then that of the primary mirror. Collimation held much better than with Newtonians I've experienced, but not as well as with a standard Schmidt-Cassegrain. That said, if you are going to use the scope for imaging, take the time to tune it and it will exceed your expectations. Another benefit of the design is that the fixed primary mirror eliminates the mirror shift that plagues Cassengrains that accomplish focus by moving the primary. While the rack and pinion focuser with which the
scope was equipped was a pleasure to use, I recommend adding a JMI “Motofocus” to that focuser for convenient, hands-off focusing. This makes achieving optimum image focus a much faster, less frustrating process. There are a ton of little things that add up to make this telescope a joy to work with: simple things like a built in camera bracket to more advanced features like a 60mm visual back that illuminates 2-inch eyepieces without vignetteing. After adding a few accessories such as anti-vibration pads, Vixen's optional f/6.4 focal reducer, and the JMI Motofocus unit, I would agree with Vixen Optics that this is one of the best telescopes available for astroimaging. This telescope is a good value for the astronomer that is ready to get serious about astrophotography. I rate this telescope a 9/10 for the imager, but would recommend a more traditional SchmidtCassegrain for the visual only astronomer, as they would find more aperture and contrast for the same cost. As you can tell, I was really impressed with this scope and couldn’t wait to take it out to clear, dark skies.
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VIXEN VC 200L Finally the new moon arrived and I joined an informal gathering of astronomy enthusiasts at Mount Pinos Recreation Area. Operated by the U. S. Forestry Service, the observing site is a large paved parking area at the very end of a paved road (no lights in the parking lot). A summer evening at the Pinos observing site, which sits at an elevation about of about 8,300 feet, can get pretty chilly after sunset requiring a light jacket. In winter months it is much colder, which means there are sometimes only a handful of people viewing. However, in the summer there can be more than 150 people enjoying the dark skies, which was the case when I took the VC200L out for its paces. And the skies were dark this night, offering excellent viewing conditions. It took me a couple of hours to get set up, and then for the next six hours I was entranced with using the scope. I have to say, having the complete package with the Sphinx Mount and STARBOOK S, which incorporates Vixen’s GOTO controller with a built in star chart that shows you exactly where the telescope is pointing and displays “what’s up” right now, just makes constellation surfing so easy and I was able to explore so much more of the sky than I was used to! That night I shot over 200 short exposures until finally knocking off. I broke everything down and headed home to process the images using the Maxim DL imaging processing software. I have to say I love my Meade DSI Pro camera and LX75SN8, but the Vixen package was definitely a joy to use and I would not mind seeing one appear in my stocking on Christmas day!
M3
M27
M13 The images of M3, M13 and M27 were taken using the VC200L, Sphinx Mount and a Canon 350D DSLR. Each of the 180 second exposures were unguided, relying solely on accuracy of my initial alignment and the subsequent tracking of the Sphinx Mount.
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The Weekend Dob Base Project
“Building a Dob mount is easy. Some may wonder where to start, but the answer is obvious - if you’ve already got a Dob mount, then you’ve got a nice template for your new mount!”
by Erik Wilcox
The Dobsonian revolution is very much alive and well – the “Dob” may be more popular and has attained more forms than even John Dobson himself would have ever envisioned – it seems they are everywhere. Go to any star party and you’re likely to see a Dobsonian domination, with their aggressive, cannon-like OTAs ready to gobble up photons. Truss tubes, split tubes, ball scopes, and string scopes – everything from the $200 mass produced four and a half inchers to the finely crafted 30 inch that requires a trailer and ladder as standard equipment – and all sizes in between. No longer just “light buckets” – the high end and modified Dobsonians can rival apochromatic refractors in terms of contrast, but with a whole lot more aperture. If you want to see refractors at many star parties, you might be forced to look for them mounted on top of Dobs! In the past decade, mass produced Asian sourced Dobsonians have made big aperture truly affordable for all. Many years ago, a 6-inch Newtonian was considered a fairly serious instrument, and a fairly serious
investment – now, a 6-inch is among the smallest Newtonians you’ll see – at least on a Dob mount – and $250 will buy you one! Even truss tube Dobs are beginning to be mass produced, and at very consumerfriendly prices. Besides cost, the ability to easily modify Dobs makes them even more attractive. There are a host of add-ons and modifications one can make to improve performance: flocking the inside of the OTA, installing a better focuser or a curved spider, and refiguring the optics are all popular modifications, but building a better platform for your Dob might offer the biggest overall improvement. Most mass produced Dobsonians come with a heavy and somewhat clumsy base that’s usually made out of particleboard. Particleboard is inexpensive, but it presents a lot of problems. Strength is one of the biggest – screws holding the panels together can come loose over time; weight and flexure is a problem with larger scopes. I remember large chunks of the particleboard base on my 16-inch Starfinder breaking off
as I rolled it across concrete to my observing spot. And every time I tried to set the 100pound tube on the Dob base, it would flex and the tube would end up lodged down between the side panels. I think it was at that point that I decided a better mount was in order. Building a Dob mount is easy. Some may wonder where to start, but the answer is obvious – if you’ve already got a Dob mount, then you’ve got a nice template for your new mount! It’s that simple. Buy a sheet of quality plywood (I’ve found the 3/4inch Birch hardwood plywood to be an excellent material that’s also reasonably priced) – except for the largest scopes, one 4foot by 8-foot sheet will likely be plenty. Next, disassemble your current Dob base. You can place each component of the old base on top of the sheet of uncut plywood. This will give you an idea of how to most efficiently plan your cuts. Then, simply use a pencil and “trace” the outline of the mount components onto the plywood. You may want to evaluate whether the old base was designed to the right dimenAstronomy TECHNOLOGY TODAY
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THE WEEKEND DOB BASE PROJECT
View of base with right side panel removed.
all the pieces for your new mount, the temptation might be to screw it all together and be done with it – but not so fast! Remember the part about particleboard being heavy, but without much strength? A nice piece of plywood doesn’t have those issues. For that reason, you may consider cutting out more material from the front and side panels. This will save weight, and, if done right, the stability won’t be sacrificed either. For scopes over 10 inches, cutouts in the panels can make a big difference in weight (several pounds). Just make sure that the cutouts don’t affect how the scope moves; for example, you don’t want the scope to make contact with one of the cutouts in its range of motion. On many Asian-made Dobs, a sort of “double-hub” is used to avoid contact between the OTA and side panels, but many older models simply use a piece of Nylon or PTFE mounted on the side of the tube. If
Installing the right side panel.
the latter is the case, you’ll want to make the cuts so this piece doesn’t make contact with the cutouts – or move the bearing piece to a different spot on the tube. Another way to save weight is to cut the very bottom baseboard into a triangular shape instead of the round shape seen on many Dobs. On a smaller scope, the cutouts can also serve another purpose. All of the mounts I’ve built have been collapsible for easy transport, and a simple way to do that with a small base is to drill holes vertically through the baseboard (make sure these are in spots where nothing – like the bearing pads mounted between the bottom sections of the base will come into contact with them as the scope moves in azimuth) and up through the side panels so that a long bolt can be installed. You can then install wing nuts on the other end, inside the cutout. This makes disassembly without tools easy to do in the dark. For scopes of 8 inches or
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sions: height, etc. I was able to take 3 inches off of the height of my original Starfinder base without the OTA making contact with the baseboard. The solution, of course, was to simply cut the front and side panels shorter. I’ve found similar issues on other Dobs, so it pays to take the time and see if any improvements can be made in the measurements of your new base – just make sure you don’t take too much off the height and cause the OTA to make contact with the base at any point. A simple jigsaw will work fine for making the cuts, although a table saw may make them straighter. If you’re using a jigsaw, take your time and make sure the cuts are as straight as possible. I believe in function over form, but it’s still nice to build something you can be proud of! You’ll also want to drill the hole in the center of the round baseboards at this time, and make sure any nylon shims fit nicely inside the hole. After cutting
Another angle of base with right side panel removed.
www.catseyecollimation.com 46
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THE WEEKEND DOB BASE PROJECT
View from the rear of the assembled base.
less, two wing nuts per side, one in the front panel cutout as well, and one or two on each side connecting the three panels together, are sufficient. For larger scopes, you might want to install more bolts and wing nuts, or use a different method for a collapsing mount – more on that later. Next, you’ll want to sand the cuts smooth. Medium grit sandpaper (around 120 grit) works well enough. You can finish it off with some fine sandpaper (220 grit) to make everything nice and smooth. Make sure that the “U” sections where the altitude hubs sit are nice, smooth, and even, so that the scope will glide perfectly across the surface of the bearing strips. Finally, you’re ready to stain or varnish the wood. This is important, not just for looks, but also to keep moisture out of the wood during those nights when dew may be a problem (in some places, that’s every night!). There are lots of different stains to
View showing details of one of the side panels.
choose from. I’ve had good luck with the Minwax brand wood finishes, and they’re available in many different shades. The Minwax stuff stains and seals, and it only costs a few dollars. A 1/2 pint will be plenty for most projects. Make sure the surface is clean and free of any dust left over from sanding. Apply the stain evenly with a brush suitable for oil based products, avoiding runs, and allow it to dry. You can add a second coat after a few hours, if desired. Finally, you’ll want to add bearing material to the round baseboard. You could use the ones from your old mount, but the PTFE or Nylon used on many mass produced Dobs isn’t of the best quality, so you may consider buying some new virgin PTFE – it’s available through many sources, including ScopeStuff (www.scopestuff.com) and Meridian Telescopes (www.meridiantelescopes.com). Magic Sliders brand bearings and similar products can also work well for
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THE WEEKEND DOB BASE PROJECT
Another angle of the assembled base.
smaller scopes, but make sure to buy the ones that fastened with screws. I usually remove any foam tape on them, as the foam can introduce a bit of “slop” into the motions of the scope. Mount the sliders directly to the baseboard and/or the altitude hub arms on the side panels. For large scopes, I’ve found that steel “Lazy Susans” work very well, although many seem to either love or hate them.
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Above view of the assembled base.
There is literally no friction with the Lazy Susans, so friction must be introduced to keep the scope in place in azimuth. There are several ways of accomplishing this. You can use some sort of “shim” that rubs against the bottom of the top round baseboard, tighten the center bolt a bit more, or install some sort of “brake.” I've found that installing a few Magic Sliders provided just the right height to act as an efficient “friction brake” on my 16-inch Dob when using a 12-inch Lazy Susan as the main azimuth bearing. For medium sized scopes, Ebony Star laminate also works very well in conjunction with virgin PTFE. However, with a very heavy OTA, a Lazy Susan is the easiest way to get a silky smooth azimuth motion, in my opinion. Earlier in this article, I mentioned the collapsing aspect of building a mount. Unless you plan on never transporting the scope, I can see no reason not to make the mount collapsible. It just makes dark sky trips so much easier! After trying many different scenarios and designs, I found that the easiest way to make a large mount collapsible without it having a hundred bolts and wing nuts, and while still maintaining structural stability, is to use a “slot” system. I’ve never seen another mount utilize this design, but it’s worked great for me. Here’s how to do it: For my 16-inch mount, I used four square 1-inch by 1-inch by 6-inch pieces of Poplar strips. These pre-cut pieces of wood are commonly available at most home
A base that supports a Meade 4.5-inch Newt - simple and effective. improvement stores. I cut the wood into eight two-foot long sections for the side panels, with two 16-inch sections and two 14inch sections for the vertical sections of the front panel where it meets the side panels. Finally, two four-inch sections are cut to serve as bracing for the bottom of the front panel. I attach the strips, two high, to the round top baseboard so that the side panels slide down in between them. In other words, just a hair over 3/4 inches apart. Then I installed long 10-24 bolts, facing outward, horizontally through the top piece of the slots. I then installed plastic hand knobs on the outside end of the bolts. This makes assembly and teardown easy. Finally, I cut out long, thin “U” shapes into the bottom of the side panels so these fit over the bolts that go horizontally through the slots. I permanently mounted the 16-inch and 14inch slots on the front of the side panels so that the front panel section slides securely between the slots. Finally, I mounted the four-inch sections onto the top baseboard so that the front panel would sit between the slots. This all sounds much more complicated than it really is – the pictures illustrate how the base fits together much better than can be described in words. The final pieces of the puzzle are two small “C” clamps mounted to the edges of the front panels. This is why one of the vertical slots is 16 inches and the other is 14 inches. One side of the “C” clamp is placed directly on the front panel above the 14-inch
THE WEEKEND DOB BASE PROJECT slot, and the other side is tightened onto to the 16-inch slot on the side panels. This keeps the front and side panels locked together securely, with great stability. I played with some other ideas, but the “C” clamps, combined with the slot system, seemed to be the easiest and most cost effective solution to holding the three sections together on a large base. For smaller mounts, the long bolts and wing nuts work great, and are pretty much self-explanatory. With either method, you obviously want to avoid mounting screws or bolts where they would come into contact with the bearings on the bottom baseboard as it moves in azimuth. For my 16-inch base project, I replaced the woefully undersized hubs with some 14.5-inch hubs from AstroSystems (www.astrosystems.biz). The general rule is that the altitude hubs should be 1.5 times the size of the primary mirror, but I didn’t want 24-inch hubs! In moderation, smaller hubs can be just as smooth as larger hubs, but the scope may be more sensitive to balance issues. In any case, you don’t want 5inch hubs on a 16-inch scope, and if you’re building a base, it’s a good time to evaluate the altitude hubs. I also added some casters with wheel locks to the groundboard – this makes rolling the fully assembled scope easy, and you can lock the casters so the base doesn’t move around when slewing the scope. The 16-inch base is the largest I’ve built, and despite the unorthodox design, it works flawlessly. With the slot hand knobs tightened down, I can pick up the entire assembly by the side panels, and it won’t come apart – that aspect was very important to me. The motions are very smooth, and tracking at magnifications of more than 500X is easy, with no backlash. In addition, unlike the stock 70-pound particleboard base, I can actually lift the Birch base easily, as it tips the scales at just over 40 pounds. Whether you have a 6-inch or 16-inch Dob, replacing the particleboard base with a home built plywood base is a cinch with just simple tools – you don’t need a fully equipped workshop. So give it a try- it might be the best $80 upgrade you’ve ever done – and is very easy!
The new Astro-Physics 6" Eagle Adjustable Folding Pier is a versatile work-of-art as well as a totally practical tool for the advanced imager. The one piece assembly sets up quickly in the field and allows adjustment of pier height, leveling of the mount, and eases the process of polar alignment.
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While astronomy can be a solitary activity, it is interesting to experience the camaraderie that people share when they get together to gaze at the stars. And, although we can’t cover every star party and astronomical get-together hosted throughout the country, we try to regularly offer our readers a look at what is and has happened. July was definitely a banner month for astronomy related events, and interestingly, this month we report on three events that stretched across the nation. On the west coast, OPT hosted its Third Annual SCAE, in the nation’s heartland the inaugural EPOCH 2007 was hosted by 20/20 Telescopes, and farther east the National Radio Astronomy Observatory in Green Bank, West Virginia, was the site of the Green Bank Star Quest. Alas, we missed all three! However, we were lucky enough to receive reports from each event and we are glad to bring them to you!
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Top photo: This 30-second exposure at ISO800 was taken on July 10th by Joe Tarkanay at EPOCH 2007 with a Canon 20Da using a 15-mm lens on a regular camera tripod. The view is similar to that seen with the unaided eye. Bottom photo: Rodney Waugh’s photo of attendees at the Green Bank Star Quest.
Third Annual Southern California Astronomy Exposition The good folks at Oceanside Photo & Telescope hosted more than 1,200 people from all across the globe who converged on their headquarters in San Diego, California, to attend the SCAE. We have heard reports that Craig Weatherwax, OPT’s president and founder, was mingling with the attendees appearing in his Superman outfit, however we don’t have the pictures to prove it! The event was held over two weekends and featured seminars, a star party (yes, unfortunately there were clouds!), product demonstrations and what has to be one of the largest raffles of astronomy equipment ever held! John C. Smith, guest lecturer from NASA’s Jet Propulsion Laboratory, kicked off SCAE with an informative talk on the Cassini-Huygens Mission to Saturn and Titan. Lectures continued throughout the day by such noted speakers as Planetary Scientist, Dr. Kevin
Grazier, famed astrophotographer, Tony Hallas, San Diego's favorite astronomer, Dennis Mammana, and amateur astronomer, Stew Hall, who gallantly stepped in at the last minute to fill the time slot of cinematographer and solar imager, Gary Palmer, when he was faced with a family emergency and could not attend SCAE. In the late afternoon, prizes were awarded to the SCAE Photo Contest finalists, including First Place winners Jeff Lunglhofer, for his beautiful image of Rho Ophiuchus, and to John Laborde, who photographed an enviable southerly view of the Milky Way from his personal observatory. Evening festivities included a free chuck wagon barbecue and star party at San Pasqual Battlefield State Historic Park, located about 30 miles east of OPT, and resulted in a crowd of over 200 people, in spite of dense clouds that draped
the sky overhead. Volunteers from California State Parks and Oceanside Photo & Telescope Astronomical Society (OPTAS) set up dozens of telescopes on the observing field and waited for the skies to clear. Unfortunately, humidity and clouds persisted into the evening, but the great majority of attendees stayed and enjoyed spirited conversations about equipment – the usual topic of conversation for a cloudy star party! Two weeks later, the OPT parking lot became a hive of activity as the muchawaited SCAE Telescope Demonstration Convention got under way. Approximately 800 people were on hand throughout the day to talk face-to-face with a multitude of representatives from superb companies like ADM, Apogee, Astrodon, Astronomy Magazine, Canon, Celestron, Chronos, Coronado, Denkmeier, Astro Hutech, The Imaging Source, Maxfactory, Meade, Pentax, QSI Imaging, SBIG, Stellarvue, Takahashi, Tele Vue, Vixen, William Optics, and Yankee Robotics. Short talks by various manufacturer representatives took place in the OPT Underground Gallery throughout the day, interrupted only by a free pizza lunch for the masses at 2 p.m. Forty large pizzas, as well as chips, cookies, and drinks, were set out and a line promptly formed. Let’s just say there will be more pizzas (especially pepperoni!) next year! The culmination of SCAE has quickly become legendary, and for good reason. The Giant Giveaway Raffle caused approximately 500 people to collectively hold their breath as Ben Hauck, Chief of Operations for OPT, called out a winning number over fifty times. Prizes totaled over $20,000, including the grand prize, a SBIG ST-7XME worth more than $2,500! As the crowd slowly dispersed, talk had already begun about “next year” – we can’t wait! For lots more photos of the event go to www.optcorp.com and click the “SCAE Event Info” link.
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Green Bank Star Quest
A BANNER MONTH FOR ASTRONOMY EVENTS O’Dell Carroll and Roy Lee Cook, who gave a talk about their activities that, along with others, led to the novel Rocket Boys and the movie “October Skies”. They also emphasized the importance of reading and education. They work with schoolteachers in several states to build interest in education among young people. Quentin sold “T” shirts that read “I SPEAK GEEK!” and the Rocket Boys were happy to autograph the shirts. NRAO staff offered high tech tours of the facilities and NRAO Education Director Sue Ann Heatherly offered an introduction to radio astronomy. Tom Crowley of Chiefland, Florida, offered hands on instruction and use of the 40-foot radio telescope for Star Quest participants. Dr. Andrew Clegg, the director of the Electromagnetic Spectrum Management
Photo above: Vendors were set up in the visitors center atrium next to the Star Light Cafe. Photo Right: A satisfied door prize winner. Photos by Rodney Waugh Once again the Central Appalachian Astronomy Club and the Kanawha Valley Astronomical Society joined up with the National Radio Astronomy Observatory at Pocahontas County’s beautiful Green Bank, and held the largest radio and optical star party in West Virginia. Four days and nights of astronomical fun for all! Rodney Waugh, President of the Kanawha Valley Astronomical Society, was very pleased with the crowds and clear skies. “Friday night and Saturday night were exceptional! The dark skies cleared to the point the Milky Way looked like a cloud. The campground and RV area was crowded with telescopes of all kinds.” “Anyone interested could travel around and look at dozens of astronomical objects thru telescopes that were shared by their owners,” he continued, “I know of no other hobby where the own-
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ers of thousands of dollars of equipment are so happy to share. The payback to the owner/operators is the comments like: ‘o-gee,’ ‘look at that,’ ‘I have never seen it that well,’ ‘it has color,’ and so on that the viewers make. Saturday night’s observing was topped off by a fireball that traveled near the Zenith and moved from North to South. It left a trail that was visible for several seconds and covered over one hundred degrees of sky!” In addition to the clear skies, the main attraction was the West Virginia Rocket Boys, Quentin Wilson, Jimmy
Program of the National Science Foundation, discussed the difficulties that are involved in keeping the frequencies used for radio astronomy clear. Besides radio and TV, a lot of everyday household items produce radio waves that must be eliminated or minimized. NRAO oper-
A BANNER MONTH FOR ASTRONOMY EVENTS ates a truck that searches for radio interference in the surrounding areas. Often an electric fence, electrical equipment, wireless Internet or even a home microwave is sniffed out by NRAO which has legal authority to enforce the rules in the Radio Quiet Zone! Several vendors set up shop in the visitor’s center and just about anything astronomical was offered. Companies selling or displaying products included Howie Glatter Collimation, Burgess Optical, Camera Concepts, Southeastern Camera, B. Crist Miniatures, R.F. Royce Precision Optical Components and Criterion Machine Company. A number of speakers offered programs each day including Robert Royce of R.F. Royce Precision Optical Components, who discussed topics ranging from composite mirrors to the next generation of amateur telescopes. “Donald Nicholson and Harold McAlister flew in from California’s Mount Wilson Observatory to speak of the history of the great institution,” said Waugh. “Don Nicholson is the sharpest 89 year old I have ever met! Don has known and worked with people such as George Hale, Edwin Hubble and Albert Einstein! His father, Seth Nicholson, discovered 4 of the moons of Jupiter!” Other programs included Mark “Indy” Kochte on the “Mercury Messenger” Project, Dr. Jack Littleton of West Virginia University on “Extrasolar Planets”, and Brent Maynard on “Webcam and DSLR Imaging”. Dr. Jim Thiemann joined the event by teleconference with “Radio Jove” and attendees listened to a Jovian storm using Radio Skypipe software. Dr. Michelle Shinn discussed a brief history of women in radio astronomy, as well as “Missing Mass, the Search for Dark Matter”. The clubs are already planning next year’s event and more information on dates and times will be available soon at www.greenbankstarquest.org.
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EPOCH 2007 Star Party and 2007 Midwest AstroImaging Conference A BANNER MONTH FOR ASTRONOMY EVENTS
EDITORS NOTE: With an attendance of over 300, EPOCH 2007 was the most attended star party event in the Midwest since AstroFest 2005. It was blessed with moderate weather – it only rained 20 minutes one afternoon during the entire week of the event. Instead of our telling you about the event, we are fortunate that Joe Tarkany, a member of the Miami Valley Astronomical Society in Dayton, Ohio, was an attendee and provided us with his behind the scenes look at the week long event. On July 8-15 I had the privilege to travel with Carl Allen to Northwestern Indiana. We were able to set up a telescope and observe every night! We stayed on location for a full week of astronomy with comfort. The accommodations included Carl’s 35 foot trailer and with it all of the amenities of home. Carl brought his Meade LX200 12-inch telescope and I had room for three small scopes. The event was called EPOCH 2007 and we were to meet other dedicated stargazers for a laid back week of observing. John d'Entremont, Rick
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Weiss, Justin and Kristie Cox would join us at Astro-Acres in the middle of cornfields. John brought his 13-inch scope. Rick brought his TV85 and Big Binoculars. Justin and Kristie brought their new 80-mm Meade refractor with the LXD55 mount. Are all nice scopes, I used and looked through all of them. Day time adventures included van transportation to tour a local dairy complete with ice cream, an ancient meteor crater, and a visit to a local observatory, the Conway Observatory. Justin attended the Astro-Imaging Conference, a two
day seminar on state of the art techniques in astrophotography and image processing. The imaging conference was held at St. Joseph’s College in Rensselaer about fourteen miles away. The event hosts provided a van for transportation to the conference. My goal was to start logging the Messier list with my 8-inch Dobsonian. The Dob holds an F/7.17, the last mirror figured at the Boonshoft Museum. It is an ultra-portable telescope; the secondary support fits inside the rocker box when transporting. A two-strut mount holds a JMI focuser where I placed a 24.5-mm eyepiece. This wide-field made the telescope easy to use. A Meade ETX105 and Tel Vue Pronto would also made the trip. Sunday night was clear, but a bit hazy to start. There are only a few lights on the horizon, maybe three miles away. The place had already made my expectations high. The Milky Way was reachable early so it promised to be a good observing week. A wireless network was available and the Clear Sky Clock for AstroAcres showed good viewing. 88.1 on the FM dial also gave reports from a big tent on location and included weather and schedule updates. In the Messier log book that I prepared I added the information: Right Ascension, Declination, Distance, Visual Brightness, and Apparent Dimension about each object from seds.org. Then I printed one object per page and placed into a binder. The requirements for the logs are taken straight from the Astronomical League web page. The sky glow to the north was seen but the south was dark, very dark. I aimed the scope south. I logged most, but not all, of Sagittarius that I saw the first night. These are objects that I can easily find. The next few nights I covered most of Ophiuchus. I am not as familiar with this constellation, so I had to go back and forth between the objects, not just to record them, but to remember
A BANNER MONTH FOR ASTRONOMY EVENTS where they are. The sky glow to the north was present again, but within a couple hours from Chicago this was remarkably dark. It was magnitude six or better to the south and you could stay up all night. It was looking good. Parked next to us was Lee Paul from St Louis. He was using a 5-inch Celestron Cassegrain. After he had help collimating the scope it showed great views of Jupiter. He went with us on day trips to restaurants or for supplies. The trips were short because there were shopping places close by. Later in the week more people moved in. Green Bay had representatives. Dave and his family had a trailer to the north of us. He was the first to find a comet. He used a modified LXD55 mount holding a computer controlled Meade AR5 refractor. Nice view and Blue tooth controlled. Ron Ravenburg, from Columbus, Ohio, with friends, settled to the east of us. Nice scopes! We wandered over to them and mentioned the comet. I then had the privilege to use his scope to find C/2006 VZ13 (LINEAR). I looked through his 60-mm finder and the comet was visible through it! Through the 10-inch it looked even better. Bill Burton said it is brighter than the reported tenth magnitude it is listed at, probably Mag 7! The location of the comet in respect to the sun lined up so a possible tail would be aimed away from the earth; so we did not see a tail. We were able to watch the comet move past the background stars. Bill brought along the telescope that Jim, of Star Splitter, made. A two strut mount Dobsonian that holds a 10-inch mirror; great optics on an easy to use portable telescope. The secondary mirror mount has been modified to eliminate the need for shroud or baffle. A bracket incorporated a block for background light while holding the secondary mirror. Ron said that extra innovations in telescope making make for a more
relaxing observing session. Ron was using the next generation design, another 10-inch, but the two poles are rotated at 45 degrees making it even easier to use. The observer could stand higher and look down towards the eyepiece. Ron mentioned the design change had to be chased throughout the scope to make it work. These telescopes are just another reason to attend an event like this. Both telescopes are magnificent to look at and a pleasure to use (see photo previous page). To the south of us were two Kendrick tents from Green Bay. One housed a Meade LX200 12-inch set up for imaging. There was an 18-inch Dob near by so we found the comet quickly. Dick responded that he and Kevin just finished the 12 recordings required for the Astronomical League observing. He documented two drawings of each of the comets that he found and submitted them to his Astronomical League coordinator (ALCOR). He was surprised on how much the comet had brightened. He called Kevin away from the 12 inch to grab a look. The last page of the log book was a page from the Astronomical League to record drawings. I went back and recorded the comet. I then used the ETX105 to see the comet. After finding the comet I was able to add an object to the database using the hand paddle. The name used was the time. I was able to record the travel of the comet using the ETX with the updated AutoStar over the next few nights. Kristie was now familiar with her 80-mm Meade and the controls to aim it. She covered Messier objects 2 through 32 in one night. The wide field framed in the Lagoon Nebula nicely. The scope was
also used to document the comet using the AutoStar hand paddle. Friday, during the day, Al Nagler displayed his newest products. One of his bigger refractors was aimed at aluminum chips on a black background. Looking through the eyepiece, “WOW!”, the eyepiece was bigger on the inside than on the outside! And a flat image all the way across the field! I want one! The Tele Vue 13-mm Ethos specifications listed the apparent Field at 100º. The Ethos is on my Christmas list. Saturday a band was playing sixties and seventies music. Al liked the music and requested some “Yes” songs. Al’s demo was behind the stage so he hung around and enjoyed the moment. He also autographed my hat while enjoying the sounds. I grabbed another look through the eyepiece. Later, Al gave his presentation “Giant Eyepieces That Swallow Spacecraft”. He explains where he came from and by his equipment you know where he is. His presentation includes his work and that of his friends. It’s a nice story with good pictures. He also signed autographs and answered questions. Kristie took the picture of Al shown above. The biggest scope on site belonged to Chris Brownwell of 20/20 (the host of the event), a 25-inch Obsession. It was set up and used with Al Nagler Friday
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A BANNER MONTH FOR ASTRONOMY EVENTS
night. I want the eyepiece. Saturday night when I went to look through it, Chris was gone. I returned a few times and found that he was servicing telescopes that some of the attendees were having problems with. Good or bad, events like this are where you can find help with your telescope. (See photo of Chris’ Obsession above)
inch Cassegrain that I was not familiar with. I think he said it had a 3150 focal length. Anyway it was aimed at Jupiter and a shadow transit of one of the moons was easily visible. Nice, but when Franz aimed at M13 he told me to call all of my friends over and tell them to take their shoes off so they can count the stars. This took a while. He also had his home built 18-inch Dob. Franz displayed it at Apollo Rendezvous and won an award for telescope making. Nice scope! I aimed at the comet for yet another nice view! Friday, at dawn, we saw the crescent moon rising above distant cornfields. I
While walking back and forth to the Obsession, I walked by two Astro Physics mounts. One had a 6-inch F/7 refractor aimed at Jupiter. Nice view! The other is owned by Franz Frederick who had a 10-
captured the moon using eyepiece projection. The camera was aimed through a 56-mm eyepiece looking through the Pronto. Yes, I was holding the camera in my hand.
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Chris, Wes and Jon, from 20/20, did an excellent effort hosting EPOCH 2007. They asked for opinions on what to do next. If any one needed a ride somewhere they supplied a van and driver. This made it nice for those who did not know the area. They did make merchandise available under a big tent the whole week the event was in progress; including eyepieces, telescopes and accessories. There were some great buys of new and used equipment. An Internet connection provided quick credit card response, and they shared the Internet with a wireless connection to the observing field. For door prizes, shopping sprees were awarded totaling $4,000. The shopping spree award winners were able to select anything on hand, or normally stocked merchandise at 20/20. Nice! Yes, I will go back to Epoch 2007, and they plan for another week next year. The understanding from the other dedicated stargazers is that they will also return.
Impatience is the Mother of Invention The Starizona MicroTouch Autofocuser
By Scott Tucker
A couple of months ago I wrote in this magazine about how technology such as CCD cameras and the HyperStar system were making astrophotography much simpler. And, while I certainly praised the fact that this made the process of imaging more enjoyable and opened up this aspect of our hobby to many more people, I may have lamented a bit the demise of the suffering that used to be required to take astrophotos. It didn’t seem right that it should be so easy. Of course, I’m not really complaining about saving time and trouble. I’m fine with not going back to suffering for astrophotos. A major nuisance of deep-sky imaging was the process of focusing. The MicroTouch Autofocuser, available in both wired and wireless models, is a powerful and precise motorized focuser that helps turn focusing from a dreaded, time-consuming, arduous task, into a simple click of a button. The Way it Was Thinking back to my days (or nights, rather) of film astrophotography, it never ceases to amaze me how far we’ve come technologically in less than a decade. My
first astrophotos were focused by just looking through the camera viewfinder and hoping for the best. This resulted in some, shall we say, less than successful results. Take for instance the night I drove 150 miles to reach skies darker than the inside of a cow, only to take eight hours of out-offocus astrophotos. I decided that was unacceptable, although that may not have been the exact term I used at the time. So I upgraded to using a high-power loupe to magnify the image on the groundglass in the camera’s viewfinder. This helped a bit, but was still a hit or miss proposition. Next was the only surefire method of focusing a film camera: the knife-edge focuser. Mine was built from an old plastic CD case, a piece of film, some tape and a couple rubber bands. And it was about as easy to use as a piece of film taped to a CD case and attached to a camera with rubber bands – which is to say, not very. The jump to CCD technology alone was a huge leap forward in the ease and consistency of focusing. Imagine the difference between, say, trying to hit a baseball with your eyes closed versus swinging with your eyes open. Your batting average is
going to go way up. With a CCD camera you can actually get feedback from the computer on the size of a star. Make the star as small as possible and you’re golden. While my average went from below the Mendoza line to a perfect thousand, focusing remained tedious. The process still necessitates focusing by hand, and there are other hassles that make it more time-consuming than necessary. Viewing the computer screen from where you can reach the focus knob isn’t always easy. You have to touch the scope and that induces vibrations. You have to make a guess about the actual star size, since the values displayed change slightly due to atmospheric turbulence. In the end, it typically takes at least ten minutes to focus by hand. There’s room for improvement. Impatience Drives Innovation Technology saves an amazing amount of time. We used to have to wait for things like dinner, film processing, pregnancy tests. Now we get instant results, although the element of suspense is lost, for better or worse.
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Think of all the things that technology has made faster and easier: e-mail, for example. Remember when you used to have to walk all the way to the mailbox to get unsolicited junk? Or, consider how online dating has changed lives. You used to have take time to clean up and put on nice clothes to go to a bar. But now you can surf for prospective dates on-line from the convenience of home, while wearing a beat-up Kansas Live in Tuscaloosa 1977 T-shirt and fuzzy bunny slippers. You can’t get dates in a bar in fuzzy bunny slippers (or at least it’s never worked for me). The Internet has revolutionized activities as varied as the art of spreading rumors, the task of disseminating misinformation, and identity theft. But now technology can do something you’ll actually find useful! It can automatically focus your telescope. Plus it can do it better and faster than you. A process that used to take 10 to 15 minutes now requires only 30 seconds of your precious time. That means more time for you to work on deleting all your junk e-mail. Focusing Numbers Focusing with a CCD camera, whether manually or automatically, involves the analysis of values displayed by the software controlling the camera. The basic idea is to determine the size of the star, turn the focus knob, see if the star gets smaller or bigger, and continue turning the knob to make the star as small as possible. Doing this requires going past the actual point of best focus, because you don’t know
what the minimum size of the star will be until you’ve passed it and started to make the star bigger again. The usual value for measuring the size of a star is its full width at half max, or FWHM. Imagine a graph of the intensity of a star. A star is not a perfect pinpoint after passing through an optical system. Instead, it is brightest at its center and quickly drops off in brightness away from the center of the star image. The profile of this intensity has a bell shape, and a perfectly focused star creates a very tall, skinny bell. As the star is defocused, the bell spreads out, and the peak intensity (the top of the bell) gets lower because the light is being spread out over a larger area. The FWHM of a star is simply the width of the bell at a point halfway to the top of the bell – the full width of the star image at half its maximum intensity. The smaller the FWHM value, the smaller the star image. Also, the maximum pixel value, or the intensity of the brightest pixel in the star image, increases as FWHM decreases due to more light being concentrated in a smaller area. So what are the typical values of the FWHM? It depends greatly on the telescope, the seeing conditions and the CCD camera. This is why you have to pass the point of best focus to find the minimum FWHM value. Even with the same telescope and the same camera, it might be different than on a previous night due to changing atmospheric conditions. Ideally, it would be best to focus the
STARIZONA MICROTOUCH AUTOFOCUSER computer program knows exactly how much to move the focuser to reach a given FWHM value. It does this by initially learning your telescope system. It determines how much to move the focuser to change the FWHM value by a certain amount. Then, by measuring the current focus position and the current FWHM value, it knows how much to move to reach the minimum value. Plus it knows what the minimum value should be, based on the characteristics of your system.
telescope every time you point it to a new object. This allows correction for shifting optical components, expansion or contraction of the scope due to changes in temperature, and changes in seeing conditions. If you are manually focusing, this gets pretty old pretty quick. Technology to the rescue! Autofocusing The idea behind autofocusing is simple. It does the same thing you would do, only faster and more accurately. The software looks at the FWHM values (or a related value called the Half Flux Diameter, about which below) and moves the focuser to reach the minimum value. The advantages are many – not least of which is that you don’t have to touch the scope and induce vibrations, and of course, the usual advantage that a computer can do math faster than you. The real advantage of the softwaredriven focusing system, though, is that the
This is Where the Magic Happens The MicroTouch Autofocuser is ASCOM compatible and can be controlled by a number of software packages. The focuser ships with a copy of FocusMax, software by Larry Weber and Steve Brady. This program integrates seamlessly with camera control software such as MaxIm DL to allow easy autofocusing. FocusMax is initially calibrated to the user’s telescope system. It learns how quickly the telescope focus converges on the ideal point and how much to move the focus motor to effect a certain change in focus position. Once this is known, the software simply needs to determine whether the telescope is inside or outside of focus and the size of the star image. FocusMax uses a measurement called Half Flux. This measurement is similar to FWHM but is less sensitive to factors such as seeing conditions and light pollution. After calculating the size of the star, it is a
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simple matter of offsetting the focuser by the correct amount to reach exact focus. While an understanding of this procedure is useful, all you really need to know is that it works. I prefer to think of it the way I think of my car: I don’t need to know the exact inner workings of an internal combustion engine. I just need to know that I can put gas into it and it will get me to a Mexican restaurant. I give it fuel, it gives me burritos. The rest is just magic. You feed an autofocuser photons and it gives you perfect pinpoint stars in less than a minute. Magic! The entire process is amazingly fast. The focuser is moved to a starting position and a low-resolution image is taken of the full field of view. The brightest star is automatically detected. A high-resolution subframe is then taken of just the bright star. The focus is moved and the star is imaged again. The software then takes a sequence of five or six more images of the star to average out fluctuations due to seeing conditions. There is a dramatic 5-second pause when you think maybe something has gone terribly wrong. Then – abracapocus! – a perfectly focused star image appears on the screen and you can breathe again. Magic! The MicroTouch Autofocuser The MicroTouch was designed around the Starlight Instruments Feathertouch Focusers. These focusers are high-precision and feature 10:1 fine focus adjustments. They are available for just about any type of telescope, including popular imaging systems such as refractors and Schmidt-Cassegrains. The quality and prevalence of these focusers made them ideal for a new autofocuser system. By driving the 10:1 fine focus shaft of the Feathertouch Focuser, the MicroTouch provides extremely high accuracy. Precision is important, especially for fast-focal-ratio imaging systems such as HyperStar. A telescope with a fast focal ratio has a very narrow depth of focus, so being able to move
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STARIZONA MICROTOUCH AUTOFOCUSER the focuser in tiny increments is essential to achieving exact focus. Each pulse of the MicroTouch stepper motor equals a mere 1/300th of a revolution of the focus shaft. This allows precise focusing of even the most sensitive imaging systems. Avoiding Entanglement Having no wires attached is a lofty ideal – just ask Pinocchio. A typical CCD imaging setup has cables for telescope control, the CCD camera, an autoguider, the focuser, and power cords for all those items, plus other accessories like a dew heater. It’s only a matter of time before you trip over all those wires, hit your head, and see the wrong kind of stars. You can get wireless phones, wireless networks, wireless Internet connections, wireless remotes for your TV, and even wireless control for your telescope. Why not a wireless focuser? Aside from the coolness factor (which is always the most important thing, I think), there is a practical side. Many imagers are starting to go
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This image of the Iris Nebula was taken by Larry Moore using a HyperStar equipped Celestron C14 and Starlight Xpress SXVF-H9C one-shot color CCD camera.
STARIZONA MICROTOUCH AUTOFOCUSER remote. In the dead of winter, when the skies are clear and the temperatures are 30 degrees below comfortable, it’s nice to sit inside while your telescope suffers out in the elements. Having one less cord to run from your scope to the computer simplifies things. The wireless model of the MicroTouch Autofocuser has a range of up to 300 feet. Additional Features The MicroTouch Autofocuser also features temperature compensation. This allows the focuser to compensate for changes in focus due to the expansion or contraction of the telescope’s optics or mechanical structure. This is ideal for long-exposure imaging. The temperature compensation, and other features such as the motor speed and direction, focus position and digital readout, wireless connection, and more, can be controlled either through the MicroTouch hand control or through the stand-alone software included with the autofocuser.
Firmware updates for the hand control and motor control can also be downloaded to the autofocuser from the Starizona Web site. Autofocusing is a perfect solution for avoiding one more of the challenges of astrophotography. Wireless connectivity adds the bonus of being able to sit inside toasty warm in the winter or out of the humid bug-filled nights of summer, at your computer in your fuzzy bunny slippers, capturing images of the universe and wondering how you ever got along without all this technological magic. More details on the MicroTouch Autofocuser at www.starizona.com For tips and tutorials on focusing, see the Guide to CCD Imaging at www.starizona.com/abc/ccd/ccd.aspx. This site also features a detailed discussion on the mechanics of focusing, including depth of focus, focusing for a curved field, and focusing tolerances.
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Brainless Astronomy 101 By Jack Huerkamp
Brainless astronomy – “What’s that?” you may ask. Well, that’s a term that was introduced to me by Beth Watzke, a schoolteacher and member of the Pontchartrain Astronomy Society (PAS). She uses that phrase to describe astronomers who use “Push-To” and “Go-To” systems to aim their scopes without the need of knowing anything about the sky. Her husband, John, had a Meade LX90 and has graduated to a Meade LX200GPS – both Go-To telescopes. He too practices “brainless astronomy.” She on the other hand likes to learn the sky by star hopping with her simple but effective Orion 10-inch
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Dobsonian. For over 20 years, I used Beth’s purist approach when observing with my 17.5inch Dob, pictured bottom left when I attended the 1982 Texas Star Party. The scope wasn’t fancy, but it gave excellent views of deep sky objects. It wasn’t computerized and it had no setting circles. To locate deep sky objects, I had to pull out my star charts, climb the ladder to the finderscope and eyepiece, and with a red light shining on the map, follow a trail of stars to the target. On many occasions, I gave up in frustration – my hunt once again unsuccessful. This wasted valuable observing time in an area of the country where good nights are rare. In 1997, I retrofitted my 17.5-inch scope. Well, actually, I saved the primary mirror and burned the rest on my trash pile. I ordered an AstroSystems TeleKit to house the primary, and spent 39 months finishing it (the reasons why it took that long would fill a book). When the scope was completed, I decided to embark on a new way to observe. I added 8192 step encoders on the altitude and azimuth axes, and an Argo Navis DTC (Digital Telescope Computer).
The Argo Navis DTC, pictured above, provided the brain, letting me know how far the scope was from the desired target. By simply pushing the scope in altitude and azimuth to zero out the offset positions determined by the “black box,” I was able to locate targets. However, this was not a true Go-To system – it was Push-To. While at the 2003 Mid-South Stargaze, I ran into Jim Nadeau, the owner of NightSky Scopes. He is a fellow member of the PAS, and he was delivering a new 18-inch NightSky Dob to
Elliott McKinley. Elliott had ordered all the bells and whistles from Jim – including a ServoCAT. I was able to see Elliott’s scope in action at the event, and decided to make the final jump to ultimate brainless astronomy with my 17.5inch TeleKit. What’s a ServoCAT? The ServoCAT system is a complete electronics package that allows for control of a telescope using either an Argo Navis or Sky Commander control computer as the “reference.” A CAT can be used to control either a Dobsonian or an equatorially mounted telescope. “Control” means the ability to track or automatically follow the sky, slew (move around) at various speeds selectable by the user, and Go-To a specific object. I purchased StellarCAT’s “ServoCATSky” model Dobsonian retrofit kit to go along with the Argo Navis DTC I already owned. My kit included the original version of the ServoCAT system, including the controller pictured above, manufactured by Gary Myers. Version 2 of the ServoCAT is now available with
additional features such as EasyTrack, which provides tracking without the need for digital setting circles or a computer. The Sky version allows users to connect their Argo Navis or Sky Commander to the ServoCAT system without the need for a PC. It provides for tracking and full GoTo operation using the digital telescope computer as the object database! All features of the digital telescope computer remain, including object identification and search functions, including Constellation search. The system includes a full-featured wired handpad and an optional wireless handpad is also available. Handpad controlled slewing of 5 to 6 degrees per second, full Go-To, as well as other functions, provide for great control and full use of the telescope. Although a PC is not needed at the telescope, the setup of parameters is through a simple Windows utility. It is performed once and the information is stored in the controller. More than one telescope can be programmed into the software, so the controller can easily be transferred to another ServoCAT motorized scope if desired. High power viewing is made practical and comfortable because the CAT automatically and accurately tracks the target once it is located. The ServoCAT-Sky version uses the
DTC encoders mounted on the axes as an “absolute” reference. Therefore manual movement or slip (intentional or not) of the scope will not affect proper tracking rates and Go-To capability. A realignment is not required if the scope is manually moved as long as the groundboard does not change positions.
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BRAINLESS ASTRONOMY 101
ServoCAT Installation Within a week of Mid-South Stargaze 2003, I contacted Gary Myers of StellarCAT and ordered a system. The turn around time for the CAT was about 4-6 weeks, and while I waited for its arrival, I downloaded the information available on the StellarCAT Web site. This quickly revealed the first obstacle that I needed to overcome. Newer TeleKits have an advantage over older ones regarding adding the ServoCAT azimuth drive to the rocker. My scope had the original, double-thickness rocker base with pockets cut into it to reduce weight while retaining strength. As the azimuth drive requires a smooth, flat mounting surface, I needed to devise a means to fill in some of the “holes� in the rocker. I prepared a full-scale AutoCAD drawing of the inside of the rocker bottom showing all the pockets. From it, I made a template and cut out two plugs from pieces of Home Depot 3/4-inch Birch plywood. The Depot plywood was slightly thicker than that used by Randy Cunningham of AstroSystems (0.75 inch versus 0.70 inch), so I had to run the plugs through a wood planner to insure that they would not project above the tops of the pockets in the Rocker. The area containing the plugs was then covered with a section of 1/8-inch model aircraft plywood to provide a solid, smooth base for the azimuth drive. The necessary holes for the azimuth drive wheel and manual release clamp were drilled into the rocker, and the azimuth drive bolted into place. The two springs provide the necessary tension to hold the drive wheel against the edge of the round groundboard. With the azimuth drive
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Image 1
Image 2
Image 3
Image 4
BRAINLESS ASTRONOMY 101
Image 1 - Rocker Base with Two Plugs Image 2 - Plugs Covered With Plywood
Image 5
Image 3 - Azimuth Drive Assembly Image 4 - Groundboard and Azimuth Drive Wheel Image 5 - Wedge As Delivered by AstroSystems Image 6 - Finished Wedge Installed on Mirror Box Image 7 - Altitude Motor Drive Cover
Image 7
Image 6
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BRAINLESS ASTRONOMY 101
M51 – Single 28 Second Frame 28-inch, f/3.66 Starmaster
installed, attention turned to the altitude assembly and a new problem surfaced. Most Dobs have their altitude bearings separated by 60-70 degrees; but those on the TeleKit were separated by 90 degrees. With the scope aimed at either the zenith or at the horizon, there was no altitude bearing projecting above the Teflon pads. This is critical, as the drive cable must contact the altitude bearing as it leaves the drive wheel. I had to devise a solution. I drew a side view of the rocker and mirror box using AutoCAD, and developed a “wedge” to lengthen the
altitude bearing. I sent the file to Randy at AstroSystems, and within three weeks I had the prototype in hand. I sealed and varnished the wedge and screwed it onto the mirror box. The rest of the altitude cable drive installation went according to the instructions. I had previously made a laptop table that mounted to the rocker using the wheelbarrow handle T-nuts. However, now that the altitude drive had been installed, I needed to modify the leg on my laptop table. The altitude drive motor was right in the way. I fabricated a box out of 3/4inch Birch plywood to encompass the drive and removed a piece of the leg to make a place for it. It helped maintain the wonderful aesthetics of the TeleKit. With all problems solved, I was now ready for my first class in “brainless astronomy.” Due to the long stretch of bad weather that plagued the gulf south for most of the summer of
TeleKit with ServoCAT, Laptop Table and Tag-Along Battery Supply
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M1 – Single 28 Second Frame 20-inch Starmaster at f/2.5
2003, I was not able to test the ServoCAT until Monday, September 15th. The wait was worth it! I set up the scope before dark, and by 8:00 p.m., I was able to align the Argo Navis on Vega and Altair. For the next 90 minutes, the ServoCAT guided the scope to over 30 objects (one every 3 minutes), and all targets fell within the center of the 100X field of view of my 20-mm eyepiece. Once the targets were found, the ServoCAT followed them. I tested the tracking on The Blue Snowball for 10 minutes at 300X – the CAT passed the test. Prior to the CAT, observing at high powers was a problem. Constant readjustment of the scope to allow the object to track across the field of view did not allow for intense scrutiny of the target. This also presented a problem at Stargazes. I would have to constantly climb the ladder to replace the object in the field for the next observer. With tracking, subtle detail that could not be detected without tracking is now seen. Video Astronomy Because of the precision tracking provided by the ServoCAT, it is possible to utilize specialized astronomical video cameras like the MallinCam to observe. These devices effectively increase the size of your telescope. Using my 17.5-inch Dob and 2.1 second exposure B&W MallinCam PRO from my magnitude 4.5 backyard, I have seen all 4 galaxies in Hickson 34 live on the monitor. They
BRAINLESS ASTRONOMY 101
M20 – Single 56 Second Frame 17.5-inch TeleKit at f/3
NGC 6781 – Single 56 Second Frame 17.5-inch TeleKit at f/3
range from magnitude 14.7 to magnitude 18.5. While at New Mexico Skies in June of 2005. I observed all five galaxies in Hickson 50 – down to magnitude 20 – with the same scope and camera. Recently, longer integration times were added to the MallinCam, with 56 seconds being the current limit. Above are a few single frames from observing sessions held at Chiefland Astronomy Village in February and May of this year. The combination of a ServoCAT and a MallinCam provides the ultimate live viewing experience. Regarding Beth Watzke, she too has recently gone brainless. She purchased a 14.5-inch NightSky Scope with Argo Navis DTC, and she is enjoying the ability to quickly find objects by using the Push-To system. One day she will add a ServoCAT to her scope to make it fully Go-To. Questions If you have any questions on my TeleKit, the ServoCAT, or my laptop table, you can contact me at: jhuerkamp@bellsouth.net Additional information on the construction of my TeleKit and the modifications I have made to it may be seen on my website: www.WaningMoonII.com If you own a TeleKit and want to add a ServoCAT to it, you can obtain the altitude wedge from AstroSystems at www.astrosystems.biz and the ServoCAT at www.stellarcat.com. Astronomy TECHNOLOGY TODAY
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Reader
Profile ERIC WILCOX
Editor’s Note Eric has been a monthly contributor to this magazine since it’s conception. We get many emails asking about his background in astronomy and decided to feature him in this issue’s Reader Profile. I was born in San Francisco, California, the oldest child in a large family. Though I lived in many places throughout my childhood, I grew up in a mostly urban environment. I think it was for that reason that I didn’t discover astronomy until later in life. I was always interested in science and math, but in school was often bored and uninspired. I spent a lot of time reading, as books interested me more than what I was being taught in the public school system. Carl Sagan was (and still is) my favorite; “Cosmos” first enabled me to begin to understand the basics of Relativity. Despite
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moving around quite a bit, I generally did well in school, but never had much focus or direction. I wouldn’t say that I had a “typical” childhood, but certainly an interesting one. Music has been one of my passions for as long as I can remember. I always thought it was amazing that so many sounds and moods could be expressed with just seven notes. By the time I got my first guitar, I knew that I wanted to try and express my own feelings through music. I was mostly self-taught, aside from a few courses at a local music college, and some private lessons several years later. Eventually, I also started singing, though in a very untrained and unorthodox manner that suited my roots and personality. After playing in several bands, I formed my current heavy rock band, “Bad Karma” (www.badkarmamusic.com), in 1995. We’ve released numerous CD’s, and have had the occasional minor successes with radio airplay, TV appearances, and record label showcases. After 12 years as a band, we still perform regularly. In my twenties, the astronomy bug really started to hit me. Having only owned an inexpensive department store refractor as a kid, I didn’t know what to buy. Without the Internet, I did what little research I could, and bought a 4.5” reflector. I went through many other inexpensive scopes, but was always disappointed with the views. It had to get better than this. A couple of years later, during a late night walk in San Francisco where I lived at the time, I ran into some members of John Dobson’s Sidewalk Astronomers. I’d never
seen such large scopes - Saturn was incredible through the eyepiece of the big Dob! The next day, I looked in the phone book and found an Orion retail store nearby. The XT10 was my first choice, but it wouldn’t fit into the backseat of the old Z28 I had at the time, so I chose the XT8 instead. Over the next few years, I viewed many, many objects through my prized telescope, and eventually began looking online for reviews on astro-gear. It was at this time I found the Cloudy Nights Forums. I was very green, and used to dealing with music forums, where people were often confrontational. I quickly realized that amateur astronomers weren’t like that - everyone was instead very helpful, and nice. Since then, I’ve lived and breathed astronomy. My wife Kate and I were married in 2004, and in addition to playing together in our band, she enjoys astronomy as well; most often we attend star parties together. I’ve immensely enjoyed learning about optics, modifying telescopes, and experimenting with different gear. I love doing public outreach, as I want others to experience this wonderful hobby too. I eventually caught aperture fever and bought a 16-inch Meade Starfinder, which I later converted to a truss dob. After around 10,000 posts on Cloudy Nights, I became a moderator, and posting on the forum is still a part of my daily routine. Writing for ATT has been a great experience as well, which I thoroughly enjoy. I don’t have any fancy credentials or impressive catalogues of obscure objects I’ve bagged - I just love to view, and do it often!
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