ASTRONOMY
TECHNOLOGY TODAY Your Complete Guide to Astronomical Equipment
STELLARVUE NIGHTHAWK NEXT GENERATION • TMB OPTICAL PARAGON 40 NEBULOSITY IMAGE CAPTURING AND PROCESSING • DSLR DEEP-SKY IMAGING STELLAFANE DONATION SCOPE PROJECT
Volume 2 • Issue 5 May 2008 $5.00 US
The Story of Paul Van Slyke’s Black Forest Observatory
Contents Industry News
Cover Story Images - 33 Paul Van Slyke stands in the interior of the Black Forest Observatory (BFO) beside the 30-inch f/9 Dall-Kirkham Cassegrain and massive German Equatorial Mount that he constructed to serve as the primary instrument of the BFO’s collection of telescopes. The 30-inch Cassegrain features an f/3 primary mirror and ASTRONOMY 12-inch secondary mirror. Focus of the instrument is TECHNOLOGY TODAY accomplished by a motorized secondary mount that provides a full 3 feet of back focus and by a motorized 3-inch focuser of the design that later became known as the Van Slyke VSI SPF that is docked to the scope’s visual back. The mount features a solid steel 3.5-inch RA shaft fitted with a 20-inch Byers gear, while the Dec shaft carries a 12-inch Byers gear. Three independent motor systems drive each axis via a custom computer The Story of Paul Van Slyke’s Black Forest Observatory control system.
11 OPTICAL MECHANICS Constructs 48-inch Dobsonian
Your Complete Guide to Astronomical Equipment
STELLARVUE NIGHTHAWK NEXT GENERATION • TMB/BURGESS PARAGON 40 NEBULOSITY IMAGE CAPTURING AND PROCESSING • DSLR DEEP-SKY IMAGING STELLAFANE DONATION SCOPE PROJECT • THE TZEC MAUN FOUNDATION
Volume 2 • Issue 4 April 2008 $5.00 US
In This Issue 8 Editor’s Note Some Things Bear Repeating… By Gary Parkerson 30 Upcoming Events National Astronomy Day, RTMC, Texas Star Party By Dave Miller 33 Black Forest Observatory An Unpublished Story By Paul B. Van Slyke 41 Stellarvue 80ED Nighthawk The Next Generation and M1 Deluxe Alt-Az Mount is the Perfect Travel Package! By Erik Wilcox 45 Nebulosity A Certified “Best Buy” for Image Capture and Processing By David Snay 51 TMB Optical Paragon 40 Add Some “Wide-Field Variety” to Your Life By Mike Hardin
55 DSLR Deep-Sky Imaging Using a Canon DSLR and TMB-130 Refractor to get Eye Popping Images By Klaus Brasch 63 Stellafane Donation Scope Project Giving Back to Those Who Gave Us Amateur Telescope Making By Robert J. Teeter, Jr. 68 Astro Tips, Tricks, and Novel Solutions Grading Sky Transparency with an Automotive Tool By Gene Hunter
11 OCEANSIDE PHOTO & TELESCOPE Dates Announced for SCAE 2008 12 GALACTIC STONE & IRONWORKS A New Source for Meteorites 12 HALF-HITCH TELESCOPES New Company to Offer Grab and Go Mount 13 ASTROSYSTEMS Now Offering Ostahowski Optics 13 ASTRO-RUBYLITH Offers Night Vision Saving Rubylith Direct to Astronomers 14 FARPOINT ASTRONOMICAL RESEARCH To Produce a 10-inch Dall-Kirkham 16 TELE VUE OPTICS 13-mm Ethos Now a Bit More Bino-Vue Friendly 17 BACKYARD OBSERVATORIES AND TECHNICAL INNOVATIONS Announce Joint-Venture 17 ZHUMELL Announces 16-inch Truss-Dob Prototype
Astronomy TECHNOLOGY TODAY
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Contributing Writers
Contents New Products
Klaus Brasch, Ph.D., is a retired biology professor living in Arizona. Getting hooked on astronomy as a teenager through the Royal Astronomical Society of Canada and the A.L.P.O., he took his first grainy moon pictures in 1957 and has pursued astrophotography ever since. He has been widely published in books and magazines, and translated Urban Astronomy, Great Observatories of the World and New Atlas of the Moon from French into English. Klaus frequently lectures on topics ranging from astro-imaging to life in the universe to students, clubs and the public.
18 JMI TELESCOPES Another JMI Innovation – Motor Drive for the Meade LightBridge 19 ORION TELESCOPES & BINOCULARS Introduces the StarBlast 6 Astro Telescope
Mike Harden is the owner of Cosmos Apparel & Embroidery, Inc., located in Southwest Florida. He has been an amateur astronomer since childhood. He currently serves as Vice President of his local astronomy club and is active in public outreach.
Gene Hunter has been an avid amateur astronomer since he was 14 when he bought his first dime store telescope. By day Gene represents a clinical laboratory equipment company. He got the idea for a communal observing site while in California at Mount Pinos and started the BOG, or Bethune Observers Group (www.machunter.org), in Bethune, South Carolina, where 10 astronomers and telescopes call home.
Dave Miller decided after 25 year of computer software consulting and eCommerce sales, to follow his passion for astronomy. Dave now owns Durango Skies and has the opportunity to work with observatories and astronomy equipment every day.
David Snay is a retired software engineer living in central Massachusetts. He graduated from Worcester Polytechnic Institute and has been an astronomer and astrophotographer for more than 10 years. David currently pursues fine art photography, specializing in traditional black/white images.
Rob Teeter is a telescope builder and owner of Teeter's Telescopes, where he has produced over 50 custom Truss-Dobsonians since 2002. Rob graduated from Rutgers University in 2005 with a degree in Environmental Policy and from Montclair State University in 2007 with a Master's Degree in Environmental Management. Rob's current day job is as an environmental regulatory compliance consultant for a private New Jersey firm.
20 TETON TELESCOPES Announces a New Version Intes Micro M615 22 TELESCOPE ATLANTA Introduces the New T1-16 Lightweight Truss-Dob 23 STARMASTER PORTABLE TELESCOPES Introduces Three New FX Series “No Ladder” Telescopes 25 SKYSHED Introduces the G-POD, the World's First Green Observatory and the New "PZT" Configuration for POD 26 STARIZONA Announces the Hyperion Line of Astrographs
Paul B. Van Slyke is the owner of Van Slyke Instruments and operated Black Forest Observatory (BFO) offering educational outreach programs from 1986 to 2001. He is an avid ATM’r and has built a wide variety of telescopes over the years.
Erik Wilcox has been observing the sky for more than 20 years. In addition to being a longtime moderator on the popular astronomy forum at www.cloudynights.com, he recently started a new forum at www.starstuffforums.com. When he’s not viewing the sky, he sings and plays guitar in a rock band.
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Astronomy TECHNOLOGY TODAY
27 DENKMEIER OPTICAL Announces the New .85X Power x Switch for Newtonians 29 STELLARVUE TELESCOPES Introduces the Deluxe M3 Alt-Az Mount
The Supporting
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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.
20/20 Telescopes and Binoculars www.2020telescopes.com page 54
Blue Planet Optics www.blueplanetoptics.com page 72
Lumicon www.lumicon.com page 17
Adirondack Astronomy www.astrovid.com page 62
Bobs Knobs www.bobsknobs.com page 22
Meade Instruments www.meade.com page 4, 69
Catseye Collimation www.catseyecollimation.com page 35
MoonLite Telescope Accessories www.focuser.com page 40
Alpine Astronimical www.alpineastro.com page 57 Alvin Huey Observing Guides www.faintfuzzies.com page 18
Amateur Astronomy Magazine www.amateurastronomy.com page 53 APM Telescopes www.apm-telescopes.de page 28
Celestron www.celestron.com page 32 DayStar Filters www.daystarfilters.com page 21 Denkmeier www.denkmeier.com page 29 Durango Skies www.durangoskies.com page 13
Astro Telescopes www.astrotelescopes.com page 22
Far Laboratories www.farlaboratories.com page 39
Oceanside Photo and Telescope www.optcorp.com page 23 Optec www.optecinc.com page 25 Optical Mechanics www.opticalmechanics.com page 37 Ostahowski Optics www.ostahowskioptics.com page 31
Starlight Instruments www.starlightinstruments.com page 14 Stellar Piers www.stellarpiers.com page 31
Stellarvue www.stellarvue.com page 20
Quantum Scientific Imaging www.qsimaging.com page 48
Surplus Shed www.surplusshed.com page 10
Glatter Collimation www.collimator.com page 11
Rigel Systems www.rigelsys.com page 13
AstroPhoto Insight Magazine www.skyinsight.net page 53
Great Red Spot Astronomy www.greatredspot.com page 65
Rubylith www.astro-rubylith.com page 20
Green Bank Star Quest V www.greenbankstarquest.org page 67
ScopeBuggy www.scopebuggy.com page 18
Half Hitch Telescopes www.halfhitchtelescopes.com page 46
Scope City www.scopecity.com page 12
Jack’s Astro Accessories www.waningmoonii.com page 56
ScopeGuard www.scopeguard.com page 34
JMI Telescopes www.jmitelescopes.com page 15
ScopeStuff www.scopestuff.com page 31
Khan Scope Centre www.khanscope.com page 43
Scope Trader www.scopetrader.com page 31
Backyard Observatories ww.backyardobservatories.com page 26, 27
Stark Labs www.stark-labs.com page 64
ProtoStar www.fpi-protostar.com page 31
Astro Hutech www.hutech.com page 24
AstroSystems www.astrosystems.biz page 19
Starizona www.starizona.com page 52
Stellar Technologies International www.stellar-international.com page 57
Farpoint Astronomical Research www.farpointastro.com page 66
AstroShorts www.astroshorts.com page 49
SkyShed Observatories www.skyshed.com page 36
Peterson Engineering www.petersonengineering.com page 26
Astro Domes www.astrodomes.com page 64
Astro Physics www.astro-physics.com page 9, 42
Shrouds By Heather www.teeterstelescopes.com/shrouds page 25
Tele Vue Optics www.televue.com page 70, 71 Thousand Oaks Optical www.thousandoaksoptical.com page 37 Vixen Optics www.vixenoptics.com page 3 William Optics www.williamoptics.com page 2 Woodland Hills Telescopes www.whtelescopes.com page 16 ZCO www.zco.com page 44
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ASTRONOMY
TECHNOLOGY TODAY
Volume 2 • Issue 5 May 2008 Publisher Stuart Parkerson
Managing Editor Gary Parkerson
Editor’s
Note Gary Parkerson, Managing Editor
Associate Editors Russ Besancon Karol Birchfield Jessica Parkerson
Art Director Lance Palmer
Staff Photographer Jim Osborne
Web Master Richard Harris
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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Astronomy TECHNOLOGY TODAY
Some things bear repeating… A Digital Version of ATT Is Just a Few Clicks Away We’re sensitive to repeating ourselves here, but some things bear repeating as new subscribers are added to the list of ATT readers. This issue seemed an appropriate time to remind those who’ve just discovered ATT, as well as charter readers, that all issues of ATT are available to subscribers online. ATT is and will remain primarily a print journal – indeed, every page is designed from that perspective. But, because international demand for access to the magazine exceeded the cost-effective reach of the postal system, an online, digital version was created. An ancillary benefit of the online version is that it allows you to view the graphics that accompany each article in far greater resolution and fidelity than is possible in these pages. The interior pages of ATT are printed on newsprint, albeit high-quality newsprint, because it is simply the most cost-effective format available to us – it’s what allows us to bring ATT to you at ridiculously low prices. But, those pages often do a poor job of reproducing critical detail of astrophotographs and other graphics. So, when you find yourself thinking, “I can’t see a bloody thing in that – why’d they
bother?” as you view an image in this issue, please remember that a more visually pleasing version of that image is only a few mouse clicks away. In this issue, we dedicated fully four pages to images captured by Klaus Brasch while preparing his article on astrophotography with the TMB-130 Signature Series Apo and an Astro Hutech spectrum modified Canon 20D DSLR. We received four mega-bite and larger versions of each image from Klaus and they are simply stunning. Our very capable graphics guru has presented them here as well as they can be presented given the inherent limitations of newsprint. It was particularly important to us that our reproduction of the before/after, with/without comparison photos do justice to Klaus’ originals and, while you can see those differences in this print version, please do take the time to view them also on your computer monitor. As you will see with David Snay’s report on Stark Labs’ Nebulosity software in this issue, the online, digital version of the magazine offers another benefit: it allows virtually unlimited space for content and images that a finite number of print pages simply can't accommodate. David’s article relies heavily on images of various screens within which he worked when using the
software and, although we reproduced the most critical screens here, many more are included in the online version of his article. Plus, those screen images that are reproduced here are unlikely to reveal every detail that is necessary to a full appreciation of David’s description of the software. So, do yourself a favor and experience the digital version of David’s article as well. After all, for most of us, astronomy is a primarily visual experience and we may as well use technology when available to enjoy the most pleasing visual experience possible. Renewals? Is It That Time Already? Because this is the twelfth issue of ATT, a number of you have written or called to ask whether we will be notifying you of subscription renewal options before your subscriptions lapse. Rest assured, an email message will be sent to the address that you provided with your subscription well before your subscription lapses, however, many of you have a few more months before your charter subscriptions lapse. As you may recall, we introduced ATT last year with a free, three-month trial offer and many of you took advantage of that offer. Your subsequent annual subscription was, therefore, added to the three free issues, effectively increasing your subscription period to a total of 15 issues. As to the email and physical mailing addresses that are on record in our subscriber database, please remember that you may verify or change all such information directly by accessing your online member account directly. To do so, just click on the “Login” link in the header of the ATT homepage at www.astronomytechnologytoday.com. As always, should you have questions about any of this, please direct them to info@astronomytechnologytoday.com. We hope you enjoy this, our twelfth issue, as much as we have bringing it to you.
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.
www.astro-physics.com • 815-282-1513 Astronomy TECHNOLOGY TODAY
9
The Supporting
CAST
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.
20/20 Telescopes and Binoculars www.2020telescopes.com page 54
Blue Planet Optics www.blueplanetoptics.com page 72
Lumicon www.lumicon.com page 17
Adirondack Astronomy www.astrovid.com page 62
Bobs Knobs www.bobsknobs.com page 22
Meade Instruments www.meade.com page 4, 69
Catseye Collimation www.catseyecollimation.com page 35
MoonLite Telescope Accessories www.focuser.com page 40
Alpine Astronimical www.alpineastro.com page 57 Alvin Huey Observing Guides www.faintfuzzies.com page 18
Amateur Astronomy Magazine www.amateurastronomy.com page 53 APM Telescopes www.apm-telescopes.de page 28
Celestron www.celestron.com page 32 DayStar Filters www.daystarfilters.com page 21 Denkmeier www.denkmeier.com page 29 Durango Skies www.durangoskies.com page 13
Astro Telescopes www.astrotelescopes.com page 22
Far Laboratories www.farlaboratories.com page 39
Oceanside Photo and Telescope www.optcorp.com page 23 Optec www.optecinc.com page 25 Optical Mechanics www.opticalmechanics.com page 37 Ostahowski Optics www.ostahowskioptics.com page 31
Starlight Instruments www.starlightinstruments.com page 14 Stellar Piers www.stellarpiers.com page 31
Stellarvue www.stellarvue.com page 20
Quantum Scientific Imaging www.qsimaging.com page 48
Surplus Shed www.surplusshed.com page 10
Glatter Collimation www.collimator.com page 11
Rigel Systems www.rigelsys.com page 13
AstroPhoto Insight Magazine www.skyinsight.net page 53
Great Red Spot Astronomy www.greatredspot.com page 65
Rubylith www.astro-rubylith.com page 20
Green Bank Star Quest V www.greenbankstarquest.org page 67
ScopeBuggy www.scopebuggy.com page 18
Half Hitch Telescopes www.halfhitchtelescopes.com page 46
Scope City www.scopecity.com page 12
Jack’s Astro Accessories www.waningmoonii.com page 56
ScopeGuard www.scopeguard.com page 34
JMI Telescopes www.jmitelescopes.com page 15
ScopeStuff www.scopestuff.com page 31
Khan Scope Centre www.khanscope.com page 43
Scope Trader www.scopetrader.com page 31
Backyard Observatories ww.backyardobservatories.com page 26, 27
Stark Labs www.stark-labs.com page 64
ProtoStar www.fpi-protostar.com page 31
Astro Hutech www.hutech.com page 24
AstroSystems www.astrosystems.biz page 19
Starizona www.starizona.com page 52
Stellar Technologies International www.stellar-international.com page 57
Farpoint Astronomical Research www.farpointastro.com page 66
AstroShorts www.astroshorts.com page 49
SkyShed Observatories www.skyshed.com page 36
Peterson Engineering www.petersonengineering.com page 26
Astro Domes www.astrodomes.com page 64
Astro Physics www.astro-physics.com page 9, 42
Shrouds By Heather www.teeterstelescopes.com/shrouds page 25
Tele Vue Optics www.televue.com page 70, 71 Thousand Oaks Optical www.thousandoaksoptical.com page 37 Vixen Optics www.vixenoptics.com page 3 William Optics www.williamoptics.com page 2 Woodland Hills Telescopes www.whtelescopes.com page 16 ZCO www.zco.com page 44
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NEWPRODUCTS
JMI TELESCOPES Another JMI Innovation – Motor Drive for the Meade LightBridge
We know of no company that has introduced more innovation to this market than JMI and it’s doing it yet again with the development of a bolt-on motor drive system for the Meade LightBridge. The JMI Motor Drive for LightBridge,
planned for availability by June of 2008, will feature friction drives on both axes to permit free hand slewing of the scope without need of unlocking any clutches. Of course, the user will also have the option of slewing with the motor drive system instead, but most LightBridge owners may come to rely on the JMI Motor Drive more for centering and tracking objects without the vibration induced by handling the scope. This feature should prove especially important to vibration-free centering and tracking of objects at high magnification. A dual axis hand control will allow the user to control the speed of both azimuth and elevation motions at the handset. Initial installation of the Motor Drive system is easily accomplished in 30 to 45 minutes and disassembly requires
ScopeBuggy MAKING VIEWING EASIER! • • • • • • • • •
For use with most tripods, DOBs and piers Load tested to 600+ pounds Assemble in minutes for use or storage Pneumatic inflated 10” tires for soft ride Gloss Black powder coat paint Optional battery equipment tray Approx. Adjustable rear axle height, 1 1/2” to 7” Plus S&H, g USA in $30 Shipeipght 36 lbs. Anodized gold wheels Shipping w PS ground One person can move any size scope shipped U quickly and easily • Ideal for the new Meade RCX Series • Ideal for the Meade LightBridge Series Patent Pending • Ideal for scopes up to 36”
Please visit us at www.scopebuggy.com
SCOPEBUGGY P. O. Box 834 Elephant Butte, NM 87935 Toll Free: 866-312-8449 18
WE ACCEPT: VISA – MASTERCARD – AMERICAN EXPRESS PAYPAL – MONEY ORDERS – CASHIERS CHECKS
Astronomy TECHNOLOGY TODAY
only the removal of the single elevation clutch tension knob. A critical feature of the system is its provision for automatic centering of the elevation tangent arm with the press of a single button – a feature that should be of particular interest to those of us who’ve experienced the frustration of running into the end of the range of motion of a tangent arm drive with no way to tell whether we’ve re-centered it other than to slew in the opposite direction while trying to hand-feel the center of the tangent screw in the dark. Pictured is a 12-inch Meade LightBridge mounted on JMI’s Wheeley Bars for LightBridge and with the Motor Drive for LightBridge installed. The projected price for the Motor Drive system for the 12-inch LightBridge is just $349. For further developments, please watch www.jmitelescopes.com.
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"At The Eyepiece" Observing Guides by Alvin Huey Hickson Group Observer's Guide Abell Planetary Nebulae Observer's Guide Observing the Arp Peculiar Galaxies
www.faintfuzzies.com
NEWPRODUCTS
ORION TELESCOPES & BINOCULARS Introduces the StarBlast 6 Astro Telescope
SPECIFICATIONS
Orion Telescopes & Binoculars has introduced a larger, 6-inch version of its popular and versatile StarBlast Astro Telescope. Like its smaller cousin, the StarBlast 6 is designed to provide a fun, user-friendly platform for new astronomers, but, also like its smaller 4.5-inch cousin, it’s destined to be as popular with seasoned observers who appreciate the bright, wide-field views that the StarBlast made famous. The StarBlast 6 is compact and portable, weighing in at only 23.5 pounds and sports a built-in carry handles in the base. The sturdy swivel base is shipped pre-assembled for easy setup and the package includes 10- and 25-mm Sirius Plossl eyepieces, an Orion EZ Finder II, and a convenient eyepiece rack. The StarBlast 6 mount features Teflon bearings and adjustable altitude tension for smooth, predictable motions in both axes. The StarBlast 6 also features Orion’s world famous customer service and a one-year limited warranty. For more information, visit www.telescope.com.
Aperture ...........................................................................................150 mm Focal Length......................................................................................750 mm Focal Ratio............................................................................................f/5.0 Optic Type.......................................................................................Parabolic Glass Material.........................................................................Soda-Lime Plate Optical Quality ......................................................................Diffraction Limited Focuser ........................................................................1.25-inch Rack & Pinion Secondary Mirror Obstruction ...............................................................1.85-inch Secondary Obstruction by Diameter ..............................................................31% Secondary Obstruction by Area .....................................................................9% Mirror Coatings/Over-coatings ..........................................Aluminum/Silicon Dioxide Mount Style ..................................................................................Alt-Azimuth Mount Bearings ....................................................................................Teflon Tube Material ........................................................................................Steel Mount Material .....................................................................................Wood Length of Optical Tube .....................................................................28.0 inches Weight of Optical Tube ....................................................................12.0 pounds Weight of Mount............................................................................11.5 pounds Weight Fully Assembled ..................................................................23.5 pounds
Astronomy TECHNOLOGY TODAY
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NEWPRODUCTS
TETON TELESCOPES Announces a New Version Intes Micro M615
Rubylith Saves Your Night Vision! Rubylith comes in 15×20 inch sheets and can be used to cover anything that emits light. It’s sturdy enough to be reused and flexible enough to cover flashlights, led lights, etc…and of course it’s ideal for computer monitors. It actually increases contrast on monitors for better seeing in the dark!
www.astro-rubylith.com
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Astronomy TECHNOLOGY TODAY
At the request of Teton Telescopes’ Mark Rieck, Intes Micro has produced a 6-inch Maksutov-Cassegrain with a central obstruction formed by the secondary mirror of only 25 percent of aperture, optimizing the instrument for high-contrast, high-magnification views. The new version has been designated the M615. Reduction of the diameter of the secondary does, of necessity, decrease the size of the illuminated field, but for lunar, planetary and double star observation and imaging requiring optimum contrast, this is a more than acceptable tradeoff. The new version M615 was available beginning April 2008 and features a padded, flexible carry case, integral tube carry handle, a 10x50 finder scope with illuminator port and quick release six-point bracket, a piggyback camera adapter, two mounting bases for the finder or camera
adapter, a 2-inch visual back and star diagonal with 1.25-inch adapter. The rear port of the scope is threaded T2 for accessories. The f/10 M603, with its 34 percent central obstruction and larger illuminated field, is still an ideal choice for general purpose observation and imaging. For more information on this and other Intes Micro instruments, please visit www.tetontelescope.com.
SPECIFICATIONS Aperture ...............152 mm/6 inches Focal ratio .............................f/15 Focal length .......2280 mm/90 inches Lens ....................................BK7 Coating........Broadband multi-coated Mirror.........................LK5 (Pyrex) Coating ............95 percent reflective CO ................25 percent of aperture Optics.......1/8 Wave Peak to Valley + Tube ............................Aluminum Finish ................................White Focus .......Zero-shift moving primary Weight .....4.9 kilograms/10.8 pounds Length .............440 mm/17.3 inches Diameter ............198 mm/7.8inches
NEWPRODUCTS
TELESCOPE ATLANTA Introduces the New T1-16 Lightweight Truss-Dob Dan Llewellyn, owner of Telescope Atlanta, has announced the introduction of its new T1 series of Ultra-Light Dobsonian Telescopes. David Roberts, telescope designer/engineer, and Dan Llewellyn, owner/engineer, have combined their talents to offer the T1-16, a futuristic minimalist Dob which its producers claim packs as much performance, pound for pound, as any telescope in production. Sporting a 16-inch f/4.1 primary mirror, the focal length is 64.5 inches, and the entire scope comes in at an amazingly light 69 pounds, making it, according to Llewellyn, the lightest 16-inch Dob that he knows of. The heaviest piece for transport is the mirror cell, which is 39 pounds and easily carried by one person. The T1-16 was designed to accomplish four goals: (1) To keep the overall size, weight and ease of assembly manageable for one person. Llewellyn reports that, in less than five minutes, one can lift the scope out of the vehicle, assemble it, and be ready for observing. The height of the eyepiece at zenith should eliminate the need of a ladder for most people. Llewellyn maintains that the design results in “…no more transport worries, or fear of being up on a ladder late at night. A person 5 foot 3 inches needs no ladder at the zenith with the T1-16.” (2) Convenience of transport. Says Llewellyn, “We wanted the scope to fit in a subcompact car, so one could drive to their favorite star
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Astronomy TECHNOLOGY TODAY
party or observing site and take the vehicle that gets the best gas mileage.” (3) A clean, professional design. Llewellyn reports that the production model will use no plywood or laminate, being constructed instead of aluminum and ABS marine board. (4) Performance. Reports Llewellyn, “Only the finest mirrors from the top mirror makers are used in the T1-16. An inverted 4 vane spider and a 3.1 secondary provide spectacular planetary and deep sky views.” The T1-16, which debuted at the 2008 Mid-South Star Gaze, is preliminarily priced at $5,995 for the base model (baffle and shroud are included) and $8,995 with Argo Navis and ServoCAT Junior installed for goto and tracking. For further information, contact Dan Llewellyn at Telescope Atlanta, 404-8439610, or visit www.telescopeatlanta.com.
NEWPRODUCTS
STARMASTER PORTABLE TELESCOPES Introduces Three New FX Series “No Ladder” Telescopes Rick Singmaster was on hand at the Mid-South Star Gaze to demonstrate the newest addition to the Starmaster FX series of telescopes, a 16.5-inch f/3.7 wonder that is designed to permit feet-on-the-ground viewing for observers of even modest heights. Starmaster's FX series telescopes feature optics fabricated by Mike Lockwood from thin substrates for fast cool down.
Pictured is Jack Huerkamp of Jack's Astro fame standing next to the Starmaster FX 16.5-inch f/3.7
The Starmaster FX series also features all of the other refinements we’ve come to associate with Starmaster telescopes, including no-tool setup, quick detach mirror cell and lightweight oak primary transport case, premium components and optical coatings, all executed with Starmaster's exceptional attention to detail. Optional accessories include Starmaster’s proprietary Sky Tracker gotothen-track drive system, Sky Commander, dual hand controls, premium Feather Touch focuser, dual transport handles, secondary mirror heater, and more. The new Starmaster 16.5-inch, f/3.7 FX is available now with delivery times of three to six months. For more information on this and other Starmaster FX telescopes, please visit www.starmastertelescopes.com. Astronomy TECHNOLOGY TODAY
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NEWPRODUCTS
SKYSHED Introduces the G-POD, the World's First Green Observatory and the New "PZT" Configuration for POD SkyShed POD's principal, Wayne Parker, has announced that his popular POD (Personal Observatory Dome) is now available in a version that is produced completely from recycled plastic (Re-HDPE). This new version will be designated the G-POD (“G” for “Green”). It will boast all of the UV factors and longevity of the original POD constructed of “virgin” HDPE and, like the original POD, is designed to last for decades. SkyShed's G-POD will initially be available in the colors tan and gray and will include all other enhancements that are now available with the original POD, including the new environmentally friendly Ecomate hardened insulation and black lining for POD Bays. The G-POD will be available in all models including the standard sized POD, as well as the XL3 and XL5 versions. SkyShed even uses 100 percent recycled HDPE in construction of all optional Bay linings that are delivered
with the G-POD. The new SkyShed PZT (Portable Zenith Table) provides unobstructed views of the zenith for those few scope/mount combinations that heretofore have had difficulty accessing objects nearest zenith with the standard POD configuration. The PZT permits slewing through zenith from horizon to horizon without need of moving the dome at all, accommodating the longest duration images regardless of scope/mount design. The PZT mounts flush with the bottom of the primary dome flange and the outside Wall/Bay sections. Whenever you desire, simply and easily slide the entire open dome onto the PZT to provide an even greater unobstructed view of the night sky than is available with the standard POD configuration. The PZT is two feet deep, providing very generous clearance near zenith without need of mount offset.
Following plans available free on the SkyShed POD website, the POD owner can easily construct the PZT using materials readily available from most home-improvement stores. A complete, ready to install version will also soon be available directly from SkyShed. For more information on both of these two new SkyShed POD options, please visit www.skyshedpod.com.
Astronomy TECHNOLOGY TODAY
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NEWPRODUCTS
STARIZONA Announces the Hyperion Line of Astrographs Starizona has announced its new Hyperion line of telescopes designed with the specific goal of achieving the ultimate highresolution imaging system. With extremely high performance over a large field of view, the Hyperion outperforms the competition in its class, while costing significantly less. The first Hyperion telescope to be placed into production is a 12.5-inch f/8 model. The Hyperion produces a 70-mm (1.6 degree) diffraction-limited image circle, producing a flat, aberration-free field and pinpoint star images throughout the large field of view. The Hyperion uses a modified Cassegrain optical design. While providing high performance, the simplicity of this design produces a relatively inexpensive telescope. Despite its lower price point compared to other telescopes in its class, there are no sacrifices in mechanical quality. Components are CNC-machined aluminum and a comprehensive set of standard features are included. Standard features of the Hyperion include a large 3.5-inch Feather Touch focuser capable of carrying the largest camera setups and allowing for a large illuminated field, consistent with the wide, flat field produced by the Hyperion optical design. The scope also features a low thermal expansion carbon-fiber optical tube, MicroTouch temperature com-
D O B S E R VAT O R Y
Our newest offering, the Dobservatory is specifically designed for the low pivot point of DOBs allowing you to view near the horizon. The Dobservatory is available in sizes from 7'6" x 7'6" to 15'6" x 15'6".
pensating autofocuser, CNC machined 6061 aluminum construction, two Losmandy-style dovetail plates, two rear cell cooling fans for rapid thermal stabilization and two ergonomic back-plate handles for easy transport. Located in southern Arizona, Starizona manufactures both optical and mechanical accessories for telescopes, including a wireless temperature-compensating autofocuser and the popular HyperStar system. For more information and images, please visit www.hyperiontelescopes.com. SPECIFICATIONS Aperture .................12.5 inches (320 mm) Focal Ratio......................................f/8 Focal Length ...........................2540 mm Secondary Mirror Diameter .......5.5 inches Overall Length .........................39 inches (45 inches with focuser) Overall Diameter ...................15.5 inches Total Weight...........................50 pounds Price ............................To be announced
The Home Model is the perfect design of form, function and, of course, pricing with every feature you’ll need for the ultimate in observing! The Home Model is available in sizes from 7'6" x 7'6" to 15'6" x 15'6".
HOME MODEL
From Maine to California, Montana to Texas, BYO builds the highest quality roll-off roof observatories on the market today. We are now beginning our 6th year of providing turn key observatory solutions throughout the U.S. and have gained experience second to none.
Why Backyard Observatories?
DENKMEIER OPTICAL Announces the New .85X Power x Switch for Newtonians Focal reduction with a Denk Binoviewer in a Dob? Yes! Denkmeier Optical has announced a new .85X Power x Switch Reducer System for Newtonians that, for the first time, provides Newtonian users the benefits of focal reduction previously enjoyed only by SCT and refractor users. Specially designed to work with its D21 eyepieces, this new system allows the D21s to operate as if they were 24-mm 65 degree eyepieces. Any Denkmeier Binoviewer using its 2-inch OCS and Power x Switch system can be easily upgraded to add this auxiliary reducer. With a Denk Power x Switch equipped with the new .85X reducer, reduction can be implemented instantly and then removed just as instantly! Denkmeier Optical offers a true Power Switching 2-inch Optical Corrector System and now the “Reduction-Mode” makes wider field
More options, Most roll-off roof experience, 25 years construction experience, Turn-key installation, Ever customizable designs, Highest quality residential specs (not shed type construction), Heavy duty industrial capacity roller system design, Exclusive m1 OASYS roof automation, Standard and Heavy Duty roof motor designs, Big Bear Piers, Warm/Control room options, Plans available created by an experienced builder/astronomer with DIYers in mind, Our observatories have been chosen 10 to 1 over other commercially built observatories at Deerlick Astronomy Village.
BYO EXCLUSIVE
views of nebulae and galaxies possible for Newtonian owners. The .85x reduction option is designed by Russ Lederman, owner of Denkmeier Optical and longtime 20-ionch F/5 Dob user. Information will be added to the Denkmeier website, www.deepskybinoviewer.com, soon featuring photos and descriptions as well as focuser requirements.
CLUB MODEL
Our Club Model is quite probably the largest home observatory available and more bang for the buck than anything else out there! The Club Model is available in sizes from 16' x 20' to a whopping 24' x 32'!
WWW.BACKYARDOBSERVATORIES.COM • 330-667-3214 WWW.M1OASYS.COM
m1 OASYS A Backyard Observatories Exclusive! The m1 OASYS system is the ultimate Roll-OffRoof Observatory Automation/Security System. This very flexible and robust system is a must-have tool for anyone wishing to secure, monitor, and remotely control their telescope observatory and best of all, you can install it yourself! Go to www.m1oasys.com for more info.
Factory authorized sales and installations of Technical Innovations’ Home Dome, Pro Dome and other fine observatory products.
FACTORY INSTALLATIONS
BACKYARD OBSERVATORIES
NEWPRODUCTS
STELLARVUE TELESCOPES Introduces the Deluxe M3 Alt-Az Mount Stellarvue announces its new M3 AltAzimuth Mount with optional built-in computerized (push to) function. According to Vic Maris of Stellarvue, ‘This is more than a beefed up version of our small grab and go mount. We are using stainless steel shafts and large 3.5-inch bearing surfaces on both axes. This provides an extremely smooth and stable mount head that is light in weight, but will hold telescopes up to our five-inch Apo triplet!’ Originally designed for 102mm refractors, Stellarvue oversized the mount and discovered that its capacity was far greater than expected. Despite its capacity, the mount and tripod are lightweight and can be easily relocated. Two quick release, spring loaded dovetail shoes are available: one will work with the standard Vixen-style dovetail rail and the other will work with Losmandy rails. The standard M3 mount head includes an integral column and Vixen dovetail shoe. It will attach to a heavy-duty Bogen or surveyor's tripod using the standard 3/8-16 bolt and retails for $399. The version using the larger Losmandy dovetail shoe is $30 more. The computerized versions include internal encoders and the Sky Commander computer with database and connecting cables. Priced from $799, this system will take the guesswork out of locating faint objects. Customers who already own a computer (Agro Navis, NGC-MAX, Tele Vue or Sky Commander) may order the computerized version of the mount without computer for $599. Stellarvue offers a heavy duty surveyor's tripod specifically modified specifically for this mount for just $109. It is light in weight, yet more
stable than many imported aluminum tripods. The M3 can also be mounted on Stellarvue's TSL5 wooden pier tripod. Optional handles are available for the mount head allowing the user to guide the scope effortlessly across the sky. Large aluminum tension knobs allow the user to individually adjust tension for each axis for smooth yet stable operation. There is no need for slow motion controls with this mount - it operates smoothly and effortlessly, allowing the user to gently nudge the telescope from one object to another, or to follow the planets with ease. Damping time with most telescopes is under one second! For more information on the M3 Mount visit the Stellarvue website at www.stellarvue.com.
Astronomy TECHNOLOGY TODAY
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The Supporting
CAST
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.
20/20 Telescopes and Binoculars www.2020telescopes.com page 54
Blue Planet Optics www.blueplanetoptics.com page 72
Lumicon www.lumicon.com page 17
Adirondack Astronomy www.astrovid.com page 62
Bobs Knobs www.bobsknobs.com page 22
Meade Instruments www.meade.com page 4, 69
Catseye Collimation www.catseyecollimation.com page 35
MoonLite Telescope Accessories www.focuser.com page 40
Alpine Astronimical www.alpineastro.com page 57 Alvin Huey Observing Guides www.faintfuzzies.com page 18
Amateur Astronomy Magazine www.amateurastronomy.com page 53 APM Telescopes www.apm-telescopes.de page 28
Celestron www.celestron.com page 32 DayStar Filters www.daystarfilters.com page 21 Denkmeier www.denkmeier.com page 29 Durango Skies www.durangoskies.com page 13
Astro Telescopes www.astrotelescopes.com page 22
Far Laboratories www.farlaboratories.com page 39
Oceanside Photo and Telescope www.optcorp.com page 23 Optec www.optecinc.com page 25 Optical Mechanics www.opticalmechanics.com page 37 Ostahowski Optics www.ostahowskioptics.com page 31
Starlight Instruments www.starlightinstruments.com page 14 Stellar Piers www.stellarpiers.com page 31
Stellarvue www.stellarvue.com page 20
Quantum Scientific Imaging www.qsimaging.com page 48
Surplus Shed www.surplusshed.com page 10
Glatter Collimation www.collimator.com page 11
Rigel Systems www.rigelsys.com page 13
AstroPhoto Insight Magazine www.skyinsight.net page 53
Great Red Spot Astronomy www.greatredspot.com page 65
Rubylith www.astro-rubylith.com page 20
Green Bank Star Quest V www.greenbankstarquest.org page 67
ScopeBuggy www.scopebuggy.com page 18
Half Hitch Telescopes www.halfhitchtelescopes.com page 46
Scope City www.scopecity.com page 12
Jack’s Astro Accessories www.waningmoonii.com page 56
ScopeGuard www.scopeguard.com page 34
JMI Telescopes www.jmitelescopes.com page 15
ScopeStuff www.scopestuff.com page 31
Khan Scope Centre www.khanscope.com page 43
Scope Trader www.scopetrader.com page 31
Backyard Observatories ww.backyardobservatories.com page 26, 27
Stark Labs www.stark-labs.com page 64
ProtoStar www.fpi-protostar.com page 31
Astro Hutech www.hutech.com page 24
AstroSystems www.astrosystems.biz page 19
Starizona www.starizona.com page 52
Stellar Technologies International www.stellar-international.com page 57
Farpoint Astronomical Research www.farpointastro.com page 66
AstroShorts www.astroshorts.com page 49
SkyShed Observatories www.skyshed.com page 36
Peterson Engineering www.petersonengineering.com page 26
Astro Domes www.astrodomes.com page 64
Astro Physics www.astro-physics.com page 9, 42
Shrouds By Heather www.teeterstelescopes.com/shrouds page 25
Tele Vue Optics www.televue.com page 70, 71 Thousand Oaks Optical www.thousandoaksoptical.com page 37 Vixen Optics www.vixenoptics.com page 3 William Optics www.williamoptics.com page 2 Woodland Hills Telescopes www.whtelescopes.com page 16 ZCO www.zco.com page 44
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INDUSTRYNEWS
OPTICAL MECHANICS Constructs 48-inch Dobsonian Optical Mechanics of Iowa City, Iowa, has constructed a 48-inch Dobsonian for installation in the Ft. Davis, Texas, observatory of Jimi Lowrey. Constructed of aluminum and steel, the completed telescope weighs in at approximately 3,000 pounds. The massive scope features a pointing and tracking system by Gary Myers of StellarCAT that combines standard components of its ServoCAT system with custom components specifically designed to interface with OMI’s friction drive system. The scope also features digital telescope control by Wild Card Innovations’ Argo Navis system, so many large Dob owners would feel right at home using the mammoth 48-inch Dob. The primary mirror was supplied by Yuri Petrunin of Telescope Engineering
Company and was made from AstroSitall by Lomo in Russia. The Physical diameter of the primary is 48.875 inches and it is 5 inches thick with a focal ratio of f/4. The massive optic alone weighs a little over 700 pounds. The secondary mirror is an 8-inch minor axis flat made of fused quartz by Howard Johnson Optical Labs. A feature article on the design, fabrication, construction and
installation of the 48-inch Dobsonian is planned for as early as the June 2008 issue of ATT.
OCEANSIDE PHOTO & TELESCOPE Dates Announced for SCAE 2008 OPT has announced dates for the 2008 Southern California Astronomy Exposition, otherwise known as SCAE. The Seminar Symposium & Star Party will be held on Saturday, July 12, and the much anticipated Telescope Demonstration event and SCAE Giveaway is scheduled for Saturday, July 19. The SCAE Seminar Symposium will be a day filled with stimulating talks on some of the most exciting topics in astronomy by well-known professional and amateur astronomers. After the festivities at OPT’s headquarters, the event will move to the main campus of Palomar Community College for an evening under the stars with local telescope manufacturers, astronomy club members, and the telescope staff from OPT. But that's not all! Thanks to Mark Lane, the astron-
omy professor from Palomar College, OPT has secured a large lecture hall for its keynote speaker of the evening. OPT will announce the speaker and more details about this free public event soon, so stay tuned to its website! The Telescope Demonstration, taking place the following Saturday, will feature the largest and most exciting names from the telescope industry. OPT is expecting more than twenty manufacturers to attend and demonstrate their latest and greatest telescopes, CCD cameras, binoculars, accessories and more. The day will culminate with what has become one of the biggest giveaway raffles in astronomy! OPT invites all to join its professional team for one of the hottest events in astronomy. For more information, please visit www.optcorp.com.
Astronomy TECHNOLOGY TODAY
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INDUSTRYNEWS
GALACTIC STONE & IRONWORKS
HALF HITCH TELESCOPES New Company to Offer Grab and Go Mount
A New Source for Meteorites
Mike Gilmer, who has contributed to previous issues of these pages, is the driving force behind a new source for collectible meteorite specimens. Galactic Stone & Ironworks specializes in procuring rare samples of significance to collectors and scientists alike. Galactic Stone’s large inventory moves quickly with new samples being added regularly, including samples of lunar and Martian sources. The complete, current inventory can be reviewed at http://bellsouthpwp2.net/ m/o/moxibustion/meteorites.html, but Gilmer promises that, ‘If I don't have it, I can get it – just inquire.
12
Astronomy TECHNOLOGY TODAY
Charles Riddell has announced the establishment of Half Hitch Telescopes, a new company established to provide premium portable mounts at affordable prices. According to Riddell, “The all CNC machined and anodized Half Hitch is a true grab-‘n-go telescope mount that is packed with premium features, including backlash-free slow-motion controls, complete twoaxis balancing, dovetail system, preloaded Timken bearings, and caliper disc brake on the altitude axis.” The Half Hitch mount is precision bored for encoder installation and is accurately squared for reliable computerized pointing. Made from virgin aircraft-grade aluminum and stainless steel, the Half
Hitch will attach to most tripods using a standard 3/8-16 screw. Riddell continued, “At only 4.7 pounds, the Half Hitch is one of the lightest mounts available, yet its cross-braced design is exceptionally rigid. It provides excellent tripod clearance so that a tripod extension column is not needed. Moreover, its centerline loading position promotes good performance on lightweight tripods. Encoders in machined housings and a folding DSC bracket are available as options. Other accessory items will be available soon. In total, the Half Hitch is a highly engineered mount optimized as a comprehensive grab-‘n-go solution.” For more information, please visit www.halfhitchtelescope.com.
INDUSTRYNEWS
ASTROSYSTEMS
ASTRO-RUBYLITH
Now Offering Ostahowski Optics
Now Offers Night Vision Saving Rubylith Direct to Astronomers Rubylith RM3 is a high-tack ruby film coated onto a 300-gauge polyester membrane. Rubylith produces very consistent results when used to create a night vision safe red light out of standard white light sources, unlike most “quick-fix� materials such as red tape, paint and thin, colored cellophanes. Rubylith can be used to
cover anything that emits light. It is ideal for computer monitors. Many users find that it actually increases contrast on monitors. Because Rubylith is bound to a 300gauge polyester membrane, it holds its shape well when cut, is durable and is very easy to work with. For more information, visit www.astro-rubylith.com.
AstroSystems has announced that it is now offering Ostahowski optics to its customers. In addition to selling the optics themselves, AstorSystems is also offering Ostahowski optics in its line of build-ityourself Truss-Dobsonian TeleKits and its Quantum line of finished telescopes. All Ostahowski primary mirrors come with interferograms and data analysis. Interferometric documentation is supplied with every optical surface and all interferometer measurements incorporate Zygo certified reference elements. Each primary mirror is given meticulous attention to detail, including precise diamond bevels, pain-staking hand correction, and timeconsuming interferometric testing done with double pass auto collimation and Ross-Null test setups. Enhanced aluminum coatings are included in the price of the primary mirrors and each is supplied with a certified, enhanced aluminum coated secondary mirror. For more information go to www.astrosystems.com.
Astronomy TECHNOLOGY TODAY
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INDUSTRYNEWS
FARPOINT ASTRONOMICAL RESEARCH To Produce a 10-inch Dall-Kirkham
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Astronomy TECHNOLOGY TODAY
Detail of OTA back showing the cellular mirror, internal fans and LCD fan controller.
Detail of Cellular Mirror, 3.0 pounds - thermal equalization possible in < 10 minutes (depending upon initial temperature).
FarPoint Astronomical Research is developing a 254-mm Dall-Kirkham optical tube assembly for release later this year. The design will feature cast cellular optics, forced air cooling, focusing accomplished via the secondary by stepper motor, integrated microcontroller control of both focus and fan speed, and an ASCOM interface. FarPoint plans to produce 100 percent of the system in house - from hot forming the mirror blanks, optical work, testing, and optical coatings, to electronics and machining. This total control of all aspects of design and production will allow the company to produce a product of the highest degree of quality, performance, fit and finish, as well as to deliver it in a timely manner. According to FarPoint, “The telescope is being designed and produced to the highest degree of performance and craftsmanship in order to create a true connoisseur’s telescope.” Farpoint is currently prototyping this telescope system and further details of progress and test data will be presented as they become available. Progress on the prototype is: the primary Cellular mirrors have been cast, thermal equalization data has been taken against equivalent solid blanks, 96 percent reflective coatings have been designed and are being tuned and tested in FarPoint's vacuum deposition
system, in-house machining of components has begun, electronics have been procured, and code development is underway. Estimated introductory pricing will be between $6,000 and $8,000, depending upon the size of the initial production run. For those who are interested in purchasing the first run of this telescope, please contact FarPoint at orders@Farpointastro.com to be placed on the reservation list. No commitment will be required at this time, but interested buyers must be on the reservation list in order to qualify to purchase from the first run. For more information, please visit www.farpointastro.com. SPECIFICATIONS Aperture: 254 mm Focal Length: 6350 mm Focal Ratio: f/25 overall • Lightweight cellular optics for extremely rapid thermal equalization, with cooling fans • Temperature sensing on primary mirror, OTA and ambient air • Digital, stepper motor driven secondary focusing, including ASCOM interface • Integrated micro controller to coordinate fan speed and focusing • Temperature data logging • Carbon fiber tube
INDUSTRYNEWS
TELE VUE OPTICS 13-mm Ethos Now a Bit More Bino-Vue Friendly
Don’t Miss Our Triple Reward Sale Jan 18,19, 20!
Limited Time - 10% Off Tele Vueʼs Top-Rated APO Refractors! Tele Vue-60 2-el. APO 1¼” Focuser $745 OTA Tele Vue-76 2-el. APO 2” Focuser Starting at $1,190 OTA Tele Vue-85 2-el. APO, 2” Focuser Starting at $1,575 OTA
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Tele Vue-102 2-el. APO, 2” Focuser Starting at $1,995 OTA
Tele Vue-102iis 2-el. APO, 2.4” Focuser $2,685
Tele Vue-NP101 4-el. Flat-Field APO, 2” Focuser $3,295
Tele Vue-NP101is 4-el. Flat-Field APO 2.4” Focuser $3,585
Tele Vue-60is 2-el. with Flattener APO 2” Focuser $1,525
Tele Vue-NP127is 4-el. Flat-Field APO 2.4” Focuser $6,285
Astronomy TECHNOLOGY TODAY
As Vic Menard relayed in his report in the last issue of ATT on the Tele Vue 13-mm Ethos, that remarkable new eyepiece is adding a dimension to binoviewing never before reached. The 13-mm Ethos produces the same true field of view as a 26-mm Plossl, but at twice the power factor and four times the contrast factor! Unfortunately, the 63.5-mm diameter of the barrel of the 13-mm Ethos has heretofore restricted its use in binoviewers to those whose interpupilary distance equaled or exceeded that measure. While this may have adversely impacted relatively few potential users, Tele Vue elected to address the issue.
The barrel of the 13-mm Ethos has now been redesigned to reduce its diameter to 62 mm for eyepieces delivered after Mid-March of 2008. While the difference is only 1.5 mm (or 0.75 mm when pairing a first production unit a current production sample), Tele Vue decided to announce this comparatively small change for the benefit of all who want to give the Ethos a try in binoviewers – an experience that we highly recommend! For more information, please visit www.televue.com.
INDUSTRYNEWS
BACKYARD OBSERVATORIES AND TECHNICAL INNOVATIONS
ZHUMELL Announces 16-inch Truss-Dob Prototype
Announces Joint-Venture Scott Horstman of Backyard Observatories has announced that he has teamed with Technical Innovations to bring that companyâ&#x20AC;&#x2122;s Home Dome 6 and 10, Pro Dome 10 and 15, as well as the Robo-Dome complete robotic observatory, to Backyard Observatory customers. Backyard Observatories is fully factory authorized for sales and installation of all Technical Innovations domes and can therefore ship directly to the purchaser for DIY setup or construct the deck/foundation, pier and observatory, complete with automation, all as a turnkey operation. Backyard Observatories has the training and experience to cover all aspects of your most challenging observatory applications or installation sites. Technical Innovationsâ&#x20AC;&#x2122; sturdy fiberglass construction lasts a lifetime and keeps the temperature inside the dome within a few degrees of ambient. TI domes of all sizes are also available with the most economical commercially available automation system on the market today. Prices start at just $2,990 US and international shipments are available. For more information visit www.backyardobservatories.com.
Zhumell has announced that it is developing prototypes of a 16-inch f/4.5 truss-tube Dobsonian with a target introductory price of less than $2,000. Plans are that the production model will feature a 2-inch, micro-adjust 10:1 Crayford style focuser with 1.25-inch adapter. Announced factory specifications include a 16-inch parabolic primary mirror with 1/12 wave peak to peak accuracy, a focal length of 1800 mm, an 18-point flotation mirror cell with 4.7-inch cooling fan, and a roller bearing wood base. Please visit www.zhumell.com for further developments and a list of authorized dealers.
Astronomy TECHNOLOGY TODAY
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BFO in its heyday. A variety of portable scopes were used to view many celestial objects at once during evening sky tours and for portable deployment at schools, etc. By Paul B. Van Slyke
What Came Before When asked to write this article, I was hesitant because I’ve always believed that a low profile was in the best interest of my business and a quality product sells itself, without all the hype. That may sound counter-productive, from a capitalist perspective, and deserves further explanation. Perhaps a future article will include more about VSI products and my unique philosophy. I decided to accept ATT’s offer of this space because of two subjects I’ve been passionate about all my life: amateur telescope making and encouraging informed pro-space citizens. Applied properly, the former can be an exponential catalyst for the latter. The VSI website contains a slightly dated, but still topical article written about two decades ago and titled Why Space, for those who might share my adamant views on this astronomical subject (www.observatory.org/whyspace.htm).
Many years ago, the “premier” astronomy magazine asked me for an article on the Black Forest Observatory (BFO). In my youthful exuberance (and ignorance), I jumped at the offer. To make a long story short, they sat on the article and never published it. Evidently, my viewpoint had a slant they considered inappropriate or simply did not support. I will not speculate on their agenda, but know that every person/organization has one, whether they know it or not. The following is not the identical unpublished article from long ago, but it does touch on the subjects others were [then] afraid to publish, and may still be? Unfortunately, the more things change, the more they stay the same, so I must [still] offer an abridged version with a more subtle persuasion. Before I tell the revised version of the story, an overview of BFO’s construction and equipment is provided, because that is what BFO was, and ATT
is all about - telescopes and the associated equipment. The Facility Colorado’s largest observatory existed from 1986 to 2001. BFO, with its 18-foot dome and 30-inch Cassegrain, was not created for research. It was established to create a byproduct, [what I call] pro-space citizens. It was cut short by my need to eat and maintain a roof over my head - BFO was a non-profit in all aspects, especially for me. All I received from the endeavor was a giant honkin’ telescope which, in itself, could not sustain my existence. Thus, BFO finally gave way to the for-profit business, Van Slyke Instruments (VSI), but that is another story for another time. However, in its “heyday,” tens of thousands of people experienced the night sky during BFO’s short 15-year tenure. Although BFO was somewhat antiquated Astronomy TECHNOLOGY TODAY
33
BLACK FOREST OBSERVATORY “read,” if nothing else. However, if you would like to build a telescope from the ground up, and would really enjoy more than a modicum of satisfaction from this accomplishment, you may help to reignite that dying spark known as the ATM. Of course, if you really want to purchase your Meade/Celestron/etc. telescope and just look through it for all eternity, at all eternity, I’ve no objection. We truly need amateur astronomers to support the community of businesses and people, yours truly included, who try to make a living from the mechanically challenged or disinterested. BFO's warmroom/control center.
by today’s standards, it did have all the expected “pomp and glitter” of Star Wars, Stargate, and all the sci-fi genre that people have come to expect from a [then] fairly sophisticated facility. To be honest, most of those rack mounts, monitors, oscilloscopes, microfiche rear projectors (Palomar Sky Survey, etc.), joysticks, lights, gauges and switches were nothing but “eye candy” for the public, emulating the vacuity of the Stargate stage sets. However, much of that seemingly superfluous equipment did actually serve a practical function in the operation of the facility. Our three desktop computers each contributed significantly, although only one of them actually controlled the positioning of the dome and telescope. The remaining two were for general reference, sky charts, etc. This story is also about the rambling and reminiscent memories of what has become a literal dinosaur - the Amateur Telescope Maker (ATM): that miniscule minority who would rather build a telescope than look, or image
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through it. The mainstream amateur astronomy community no longer designs and builds its telescopes from society’s discards, as it once did. The typical amateur today buys a go-to mount, a tube assembly and a CCD camera. We attach the mount to the floor of a suitable structure, the tube assembly to the mount, and insert a CCD camera in the hole in the back of the scope, enjoy a long gloat period, and flaunt our images to the world. How many of today’s amateur astronomer actually built that scope? Instead, a few very expensive parts are assembled. The ATM is dead. Long live the ATM. But I am not here to evaluate today’s amateur astronomer. With apologies to those who, like me, produce those high quality and relatively expensive parts, I am here, in part, to try and rejuvenate the wonderful hobby of telescope making by reflecting (pun intended) on my story of what was, and could be again. If you have no interest in building a telescope, the following will only be of passing curiosity. Hopefully it will be an interesting
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34 Astronomy TECHNOLOGY TODAY
The Observatory Large commercial domes are expensive! That said, building your own from scratch, while a daunting task, can save much of your bankroll for the scope. You may say, “A rolloff-roof is simple, easy and adequate.” True, but it’s not as publicly acceptable or consistent with expectations as a domed observatory. People expect Mount Palomar, the Keck Twins, or better when they come to experience your observatory. Nothing less will satisfy! Comments from those who visited BFO ranged from, “This isn’t the Mount Palomar I expected…” to, “I was expecting a hut in the woods, and this is a real domed observatory. Impressive!” The dome was built by “world renown” mirror maker, Alan Raycraft, with very little [occasional] help from me. The base ring and ribs were formed from 1/2-inch plywood cut into circular hemispheres, by hand, using a jigsaw. The sectional flats were glued together, using construction adhesive, to form a rigid continuous frame structure. Yeah, I know what you’re thinking, “That’s a lot of time and tedious work!” But, remember what I suggested before, “It’s not the effort, it’s the continuing journey.” The gores were cut from 1/8-inch tempered Masonite, screwed and glued to the skeleton frame using construction adhesive. A conventional center split, bi-directional shutter was selected and built to take advantage of esthetics - a timeless symmetrical design. Long aluminum C-channel sections were built into the dome and dolly-type wheels were attached to the two shutter sections to provide easy
BLACK FOREST OBSERVATORY
Alan Raycraft and Paul Van Slyke building the skeleton frame for BFO’s 18-foot dome.
opening and closing. The dome was lifted onto the square base structure with a large construction crane. Sixteen 6-inch diameter metal wheels were attached to the square building. Two of the wheels were used in tandem, creating railroadtype wheel sets. In other words, two of the wheels were mounted on a central seesaw pivot, like a flotation arm, that applies even pressure between two of the wheels on the dome’s lower base ring. There is a materials conflict that must be noted. Metal wheels make it much easier to rotate the dome, but the metal wheels will eventually shred the plywood base ring. Using hard rubber wheels will make it much harder to rotate the dome, but the plywood laminate will not shred. My best solution was to have an 18-foot diameter, sectional sheet metal base ring made at a local sheet metal shop and attach it to the bottom of
Local astronomy club members help move the dome from its construction site to the observatory (looking like a giant white, multilegged bug).
the dome’s base ring using wood or sheet metal screws. Use at least an 8 gage (1/8-inch thickness) sheet metal or the sheet metal will also eventually shred. After initial installation, the dome was rotated, by hand, using a long rope with many “volunteers” attached to the end. Watching them rotate the dome reminded me of the Egyptian slaves moving those massive stones with simple ropes and brute force…with appropriate music - possibly the March of the Slaves by Tchaikovsky. Usually I was the marcher, not the watcher. Eventually the dome rotation was motorized along with the shutters. A box-like bracket plate was used to mount the 1/2-HP reversible AC motor, a 50:1 worm-gear reducer and a chain and sprocket turning a shaft, with a golf cart tire attached to the end and pressing against the dome’s lower base ring. I know it doesn’t sound
like it would apply enough force/torque to rotate the dome, but it worked flawlessly for 15 years with very little maintenance, even in heavy snow and ice conditions. The shutters were also motorized using two gear reduced Bodine AC reversible motors and an independent cable/pulley at each end of the shutters. If the shutter’s cables ever slipped, the motors could be individually reversed to resync the shutters. The Telescope I do not consider pushing your own glass a prerequisite to earning the title of ATM. Some may disagree. Mirror making, especially a large one, is a singular art requiring a tenacious disposition and the patience of a monk on a crusade. I have the utmost respect and admiration for the ATM who not only builds his telescope from scratch, but also grinds his own
Astronomy TECHNOLOGY TODAY
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BLACK FOREST OBSERVATORY
Spider and motorized secondary hub.
mirror. However, building your own telescope, less the optics, requires enough skill to keep most of us, including myself, busy for a very long time. I personally believe that a telescope should not be built out of wood. Wood is for furniture. I’m going to get a lot of flack for this comment, but I think there is a lot of repressed support for this philosophy. I’ve built more telescopes in my life than I can remember, and they have all been metal. No Dobs and no alt/az mounts, because they could not track. Of course, nowadays many Dobs and alt/az
36 Astronomy TECHNOLOGY TODAY
RA axis with 20-inch Byers drive and 3-motor drives.
mounts track well via computer control. All my ATM telescopes were reverse engineered from society’s discards. Yes, all of them were metal, but they were fabricated from scrap metal - a shaft here, a tube there, etc. I would slow down when passing an old culvert lying beside the road - a possible telescope pier or tube? I’d spend all day at a local scrap metal yard, mind racing with endless possibilities. That was fun to me. I know, get a life! Do you need a fancy machining facility to shape these discarded metal structures to your needs? No, but a simple metal lathe and a
Dec axis with 12-inch Mathis drive and 3-motor drives.
welder helps. However, my early telescope fabricating tools consisted largely of a bunch of files, hacksaw, and a hand drill. BFO’s 30-inch, f/9 Dall-Kirkham Cassegrain optics were fabricated, to my specifications, at a commercial facility in Utah. The 30-inch, f/3 primary mirror was mounted in an 18-point flotation cell and the 12-inch secondary mirror was mounted in a spider assembly that provided a full 3 feet of back focus range with the push of a button. To clarify, moving the motorized secondary in or out from the primary changed back focus by a
BLACK FOREST OBSERVATORY secondary mirror [primary] focusing with a large secondary focuser docked to the visual back. In other words, a scope with only one focusing capability loses a lot of functionality, especially if you do visual and imaging with the same telescope. A sigThe dome rotation motor and mechanisms. nificant change in back focus, say shortening your imaging train profile to accommodate a shorter visual/eyepiece profile, is much more convenient when you have dual focusing capability. The 3-foot diameter tube assembly was rolled from a 1/8-inch thick anodized aluminum sheet and simThe 30-inch Cassegrain primary and secondary mirrors before ply held together at the installation in the tube assembly. seam using sheet metal ratio of approximately 6 to 1. One inch of disscrews. An internal ribbing structure served a tance separation related to 6 inches of back dual purpose: providing structural stability and focus change. Of course, this is a "rule-ofinternal light baffling. Two stability trusses thumb" ratio. The primary mirror cell was were attached to the front of the tube cradle heavy die-spring loaded and collimation was and extended to the front of the tube assembly. achieved by turning three large hand wheels. Many ATMs build a telescope without conThe helical, non-rotating motorized spider was sidering the importance of primary mirror and stepper motor controlled and both were fabritube internal diameter clearance. Even a truss cated, from scratch, at my machine facility. tube can be affected by these parameters. I use The scope's visual back, which also douanother "rule of thumb" measurement for debled as the flotation system for the primary termining this clearance, which is 12 to 1. If mirror, had a motorized 3-inch rack and pinyou have a 12-inch diameter primary mirror, ion/Crayford custom designed focuser docked you need 1-inch of tube clearance between to it, providing a [front/rear] dual focusing cayour mirror and your tube. A 36-inch scope pability. It was actually the prototype for a fuwould require 3 inches around its tube. These ture focuser that would be called the VSI Super clearances are minimum - any less and tube Power Focuser (SPF) - an R&P/Crayford hycurrents will radiate into your parallel incombrid. This early design finally gave way to a ing light cone and deteriorate imaging quality. pure Crayford design that many of you may I've always preferred German equatorial remember as the Monster Focuser, now also mounts, but only if they are permanently discontinued. mounted - counterweights can be heavy to I believe that a versatile scope should have transport. Except for the occasional mechani-
cal flip-flop (crossing the meridian), an equatorial has no physical obstructions to deter pointing around the North Celestial Pole (NCP). Concerning fork mounted scopes, to me it is a "non-issue" to even consider it necessary to allow an imaging train to clear between your forks. I get this concern from so many people/clients who consider this an important factor that, when building an imaging train, they sacrifice much more important considerations just so the scope can point to the NCP unobstructed by the fork. Why? There are so few NCP celestial objects that would
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Astronomy TECHNOLOGY TODAY
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BLACK FOREST OBSERVATORY worms were connected to three independent motor drive systems: a synchronous motor for simple tracking, a pair of stepper motors for tracking and variable speed slow motion control for pushbutton centering of objects in the field of view, and a pair of matched DC servo motors with tachometer feedback and closed-loop digital The dome was loaded on the flatbed trailer before it was destroyed IC velocity controllers on I-25. Also shown is the crane that lifted the dome off the building. with ramping that procause this conflict, that to even consider it a vided tracking, slow motion and fast slewing problem is obsessive-compulsive at best. with 5 inch-pounds of torque from 3 to 5000 The BFO mount, from the ground up, rpm. All three motor systems were mechanistarted with a reinforced concrete isolation cally connected via cog pulleys and belts to a platform, 3 feet in diameter and set about 5 common shaft that drove the worm gears in feet into the ground. A 3-foot diameter cardboth axes. The stepper motor and the DC board Sonotube worked great. A 4-inch servo motor shafts rotated freely when off, and ABS/PVC conduit was installed down the centhe synchronous motor had an automatic ter and through the sidewall of the cardboard built-in magnetic clutch that disengaged the tube going to the warm-room. I found an old motor shaft when not running, so there were 14-inch cast-iron sewer pipe about 4 feet long no motor engaging conflicts along the comwith a [12-bolt pattern] flange on one end for mon motor shaft. When possible, I have althe pier, and it was free, discarded in a conways preferred to build redundant versatility struction site. The wall thickness was a more into my scopes. than adequate 3/4 of an inch. Scope movement and positioning were The German equatorial mount was deavailable from a hand paddle at the scope, a signed and created at a machine shop facility to joystick controller platform in the warm-room, which I was assigned at the time and primaor by computer. All three motor control sysrily from pieces found in the scrap metal yard tems were available at each control station of that facility. The RA shaft was machined again, redundant versatility. The acronym for from a 3.5-inch diameter, solid steel shaft, fitthe computer control positioning and dome ted with 6-inch radial ball-bearings. The Dec sync was “OTIS” (Observatory Telescope Inshaft was a salvaged stainless steel control rod terface System). A friend and I wrote the prodrive that was originally destined for a nuclear gram in Basic Pro v4. After many code power plant, but was rejected. It was not radio changes, we finally achieved a final operating active - important point! version and compiled the open code. It worked The RA shaft was equipped with a 20well for years, but the software and hardware inch Byers gear with a stainless steel worm and interface was built as a one-off proprietary systhe Dec shaft was equipped with a 12-inch tem that was specifically designed for the DC Mathis drive. The 12-inch Mathis drive was a servo motors and controllers that I acquired at little undersized, but, as noted before, when a local electronics surplus store. These hardyou are scrounging for parts, they are not alware motor controllers were surprisingly adeways a perfect fit for the application. The quate, considering they were never actually
38 Astronomy TECHNOLOGY TODAY
designed to be computer interfaced in the first place. The End of BFO BFO’s 30-inch scope and 18-foot dome were sold, long after Van Slyke Instruments had become a viable business. I eventually decided that I am only one person and VSI alone had become a virtual 3-man operation: me, myself and I. It was difficult to make a decision to liquidate an effort that consumed 15 years of my life. What really helped me accept the loss was my mental and physical condition at the time. I was totally exhausted from years of trying to maintain both businesses myself. At the time, the end of BFO was a relief. The scope was sold, dismantled and carefully packed in the buyer's truck. It is becoming operational again at a much better location at an elevation of over 9000 feet on the west side of Pikes Peak, still in Colorado. The dome was a different story. When the dome was lifted off the observatory building, it was split in two half hemispheres (it was designed that way) and loaded on a flatbed semi-trailer for its journey south. On its way down I-25, the dome sections caught a good head wind and [both] were launched off the back of the semi, tumbling down the middle of the freeway. Needless to say, they were demolished. Small pieces of dome were scattered along the highway for miles. The highway patrol was not happy with the mess either. Luckily, the dome was insured and no one injured. Of course the big hole in the center of the remaining building was a problem, so I had a framing crew build a pitched truss roof on the structure making the building whole again. My wife and I installed a nice drop ceiling, with lighting, and the old BFO is once again a viable structure supporting VSI. The lower building structure is now VSI's new office, shipping and receiving, storage and product warehouse. BFO's Educational Space Mission To return to our opening commentary and space, BFO's educational mission was to encourage pro-space citizens - to promote
BLACK FOREST OBSERVATORY
After BFO. VSI's new office, etc.
space exploration by sharing a sense of personal connection to space. Our sky tours were offered to all, from school children to senior groups. We also traveled to schools with telescopes offering daytime solar programs and provided accredited in-service courses to K-12 teachers with hands-on telescope experience. I even taught astronomy at the University of Colorado under an honorary teaching position. Initially, my most difficult challenge was how to overcome cloudy nights at the observatory. Eventually, I found an effective strategy for parting the clouds, both day and night. Was it divine intervention? No, just practical application and some techno-magic. Scheduled sessions were never weather dependent after this epiphany: I simply installed a small 2inch monitor at the focus point of the eyepiece, and connected it to the 30-inch telescope like a regular eyepiece. At first, I didn’t think the plan would work, as children are not easily excited or impressed. We didn’t try to fool them into thinking it was the real thing in real time, but visitors were able to step up to the eyepiece, look “through the telescope,” and see whatever the computer wanted them to see. Turned out, everyone loved the idea. Even though they knew it wasn’t “real,” it provided a hands-on and engaging experience. The above, and other observatory “magic,” was designed to provide the sense of connection to space necessary to creating those pro-space citizens, not from sci-fi special effects magic, but
from real magic - the catalyst created from knowledge and truth. The extended “space mission” of BFO was to provide a meaningful context for public consideration of issues relating to our connection with space (again, see Why Space for more) - for consideration of such questions as: Did our government mistake the wishes of [now] almost two generations of planet earth dwellers? Oh, we returned to space, but why did we need to return to anything? Why did we ever leave in the first place? After Apollo, the shuttle was developed, but its initial charter was to deploy dozens of military spy satellites to orbit before NASA could even begin to do any pure science and to develop space. Was NASA’s peaceful, scientific development of space deferred by the military? After all, the military had their own independent rocket program and could put spy satellites into orbit all day long. Was it governmental “bean
counter” strategy that forestalled human exploration of space? Were our representatives, from both parties, appropriately considering our long-term space interests? And finally, did we needlessly spend over a billion NASA dollars just to find out that the space plane wouldn’t work? Is our Constellation space program going “back to the future” simply by readopting Apollo-like applications? Obviously, I have definite opinions on these matters, but offer these questions to better explain the range of bigger-than-Earth issues BFO was designed to encourage the consideration of, regardless of individual conclusions reached. My rhetorical questions are meant to be constructive, not to criticize or “point fingers” at anyone or any single organization. Nor are they intended as partisan. I simply maintain that, as a species, we can’t afford many more 30-year delays in our space efforts. We may outgrow our home planet before it happens, but most of us who study astronomy know that the habitable “lifespan” of this planet is finite. However, the universe is, by comparison, infinite, with every star potentially orbited by habitable planets - there are enough extra-solar rocks out there for each of us to have our own, if we’ll only go. Think large! Is this the appropriate “place” for this discussion? Probably not. But, I hope I am talking to a receptive choir? If you own a telescope, you have all the tools you need to encourage in others a meaningful and real connection to the cosmos - especially when you create those tools with your own two hands. “The planet is in your galaxy.” As always, thanks for your continued support!
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The perfect travel package! By Erik Wilcox
When ATT asked me to review the new Stellarvue 80ED Nighthawk Next Generation and M1 Deluxe Alt-Az mount, I eagerly accepted. Aside from some quick looks through the very popular SV 80/90s at several star parties, my experience with Stellarvue telescopes was limited to one older Nighthawk. A few years back, I’d gotten to use and compare that particular telescope extensively with several other designs and came away with very positive impressions. The only areas where I thought improvement might be in order were with the rack-and-pinion focuser with which that older generation Nighthawk was equipped, finding it a bit more stiff than I prefer, and the weight of
that telescope. However, its weight was a result of the fact that it was simply built like a tank, so that’s not necessarily a bad thing. What I remember most though is that it had great optics and from the Nighthawk owners I’ve talked over the years, I’ve gathered a strong sense of intense brand loyalty. So I was very curious to see what type of travel scope Stellarvue would come up with. The Nighthawk NG and M1 Alt-Az Mount were delivered just in time for a week long trip to dark skies of our cabin site on the Big Island of Hawaii. Everything was very well packaged for shipping and arrived in perfect condition. I must say that I wasn’t expecting such a beautiful scope! This premium f/7 refractor has
a build quality that competes with many of the highest-end refractors I’ve had the pleasure of using and the Stardust white finish of the optical tube really showcases its overall looks. The rotating, dual-speed Crayford focuser is just gorgeous, with a buttery smooth action that holds its position under the heaviest eyepieces. A micrometer scale on the drawtube is also a nice, useful touch. The sliding dew shield moves back and forth with a silky ease, yet stays firmly in the fully retracted or extended positions, and the lens cap is metal, with a felt insert. A heavy duty CNC machined clamshell ring holds and balances the optical tube nicely. It has a Vixen style dovetail with a safety catch Astronomy TECHNOLOGY TODAY
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STELLARVUE’S 80ED NIGHTHAWK and a bracket for the included red dot finder. Admiring the collimatable objective lens at an angle, I could see a pretty greenhued multi-coating. The lenses appeared to almost disappear when viewed from straight on, so it seemed as though the coatings were clearly doing the job. Peering into the OTA, I could see no stray reflections or shiny objects - just a jet black tube with two baffles to further eliminate the possibility of any contrast robbing glare. Attention to detail is obvious everywhere – the focus knobs have a nice knurled grip and chrome trim gives them a classy look. The gear reduction knob is easily gripped and has a very smooth feel. Even the compression ring screw on the drawtube is chrome. The Nighthawk NG delivered to me was also “binoviewer-ready,” with a removable tube section that allows the telescope/binoviewer combination to reach focus without the addition of a Barlow of OCS as required by most fixed tube tele-
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scopes. Unfortunately, because I don’t own a binoviewer, I wasn’t able to test the scope in that configuration. The Nighthawk NG arrived with a sturdy airline-portable carrying case with the Stellarvue logo embroidered on the front. Inside, there are several pre-cut holes for eyepieces and other accessories. I carried this case onto the airplane and, in addition to the telescope and a number of accessories, had room for a few personal items and reading material (the latest issue of ATT, of course!) for the five hour flight. The zippered case has a convenient handle, as well as an adjustable shoulder strap. The M1 Deluxe Alt-Az Mount is of a very unique and innovative design. With the exception of its stabilizing section/extension bar, the mount is very light in weight. Despite the lightweight design, it proved to be a very sturdy mount. The tripod legs have three sections that, when fully extended, place the eyepiece height at nearly 6-feet (with the scope pointed at a 45-degree angle). Even with all three legs
extended, stability wasn’t noticeably affected. The stabilizing section directly under the scope’s center of gravity really does its job very well. The tripod leg sections collapse inside of each other to about 18 inches long and the stabilizing bar is easily removable (without tools) for transport, making for a very compact package. Large, knurled aluminum knobs adjust the motion tension in each axis and they work flawlessly. Motion in both axes was smooth, predictable and sure. The M1 Deluxe Alt-Az Mount that I tested included an optional handle that made slewing the scope even more convenient. Conditions couldn’t have been better for the scope’s first light. It was a moonless night and the skies at my cabin site are pristine, with no lights nearby. The site is on the slopes of Mauna Loa, at an elevation of 4,500 feet, and the limiting magnitude approximately 7 on most nights. M51 is naked eye visible when high enough in the sky (the site is at 19 degrees North Latitude) and despite a bit of VOG
STELLARVUE’S 80ED NIGHTHAWK NIGHTHAWK NG SPECIFICATIONS ment is held permanently in place, the retainer applies less pressure on those elements, eliminating pinching that can introduce optical aberrations. Mounting Rings: Stellarvue heavy duty CNC clamshell mounting with long Vixen style dovetail rail with safety catch. Dimensions: 3.5-inch diameter main tube and 4.0625-inch diameter dewshield. OTA length is 17.125 inches and 19.75 inches with the dewshield fully extended. Weight is approximately 6 pounds. Objective lens: 80-mm clear aperture, 560-mm focal length, air spaced, doublet objective. Its true ED lens was designed to provide maximum contrast and reduce false color.
Focuser: 2-inch dual speed Crayford focuser (standard model) or 2-inch Feather Touch focuser (deluxe model).
Tube assembly: All aluminum, fully baffled, precision machined optical tube assembly.
Finder: Stellarvue F1001 red dot finder included.
Lens cell: High precision aluminum, adjustable cell for accurate and stable alignment. The cell features eight contact points to hold the lens elements in position, even under impact that would cause misalignment in other designs. Because each lens ele-
(volcano fog) along the horizon from the very active Kilauea volcano, transparency was excellent overhead. On this night, M36 and M37 were naked eye, so I started with them. At 23x, both clusters looked like tiny diamonds scattered against the jet black sky, and fainter M38 was very nice as well. Over in Orion, an unfiltered view of M42 showed extensive nebulosity and the four main components of the Trapezium were easily resolved. At high power, the “E” component was visible with averted vision and installing a Thousand Oaks narrowband filter gave the nebulosity an intricate, “textured” look. At 187x, Saturn showed a plethora of detail, with the planet’s disk glowing through the translucent Crepe Ring. Despite the low tilt of the rings, the Cassini Division was visible with little effort and banding detail was quite evident on the disk - nice performance for a 3-inch scope! A star and Ronchi test showed very good optics and chromatic aberration was only visible on the brightest stars, like Sir-
Case: Included is a heavy duty travel case that holds the telescope, a diagonal, eyepieces and star charts. Price: From $599
ius. Stars really “snapped” to focus at any power. Even at high magnification, the mount was solid, with less than three seconds of dampening time needed after a solid rap on the side of the legs. For the next several nights, I had a great time with the Nighthawk NG and Mount, and the hours seemed to pass by much too quickly. Often, I found myself just scanning the Milky Way at low power to admire the star-fields, which were tight and crisp from edge to edge. Back in California, I got the scope out on several nights (under much poorer skies, of course) and by this time, the moon was waxing towards the first quarter. In focus, there was very little chromatic aberration visible at any magnification; a bit of a pale magenta along the limb if I really looked for it, but certainly nothing to complain about. I saw very little violet false color on the moon, despite its minor presence on the brightest stars. Unlike many of the medium focal ratio achromats I’ve used, I Astronomy TECHNOLOGY TODAY
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STELLARVUE’S 80ED NIGHTHAWK never felt that the very small amount of chromatic aberration in this scope detracted from the views. The moon’s deepest craters and shadows were virtually colorless and the views were simply beautiful. A low-power view showcased the moon’s earthshine and its beautiful contrast against the background sky. I’m generally not much of a lunar observer, but I’m continuously amazed at how much detail one can see with even a small scope. The Nighthawk Next Generation did not disappoint! I always find it important to mention the positives as well as any negatives in my reviews. I want the readers to get an accurate overall impression of how a product performs, as well as its specific attributes and its potential downsides. But, with this review, I must confess that I’m struggling to come up with anything remotely negative. The build quality and functional aspects of the Stellarvue 80ED Nighthawk Next Generation telescope would be very difficult to improve upon. The optics are
44 Astronomy TECHNOLOGY TODAY
excellent and though the color correction isn’t quite “apochromatic,” it’s far better than that of a standard achromat. On all but the brightest objects, I was hardpressed to see any false color; the exotic ED lens element really does the job. The focuser is extremely smooth and precise and with a slight tension adjustment, it had no problem holding my heaviest 2inch eyepieces. And the mount is simply the best travel option I’ve seen, period. The stability is much more than I expected and I love the ability to place the eyepiece height at nearly 6 feet high (I’m a tall guy). The optional 2-inch Stellarvue mirror diagonal with which the telescope was supplied is also very good, with a build quality that complements this excellent telescope. It’s often been said that there is no “perfect” telescope, as each design has its compromises and limitations. That may be true, but if the parameters are a beautifully designed and well built 80mm scope with great optics, on a stable,
yet portable mount, it would be tough to beat the Stellarvue 80 ED Nighthawk Next Generation/M1 Deluxe Alt-Az Mount combination. Whether you're considering a telescope/mount for travel or for simply setting up in your backyard, you'll be hard pressed to find a better combination of functional optical excellence and convenient, stable mounting. Having experienced its latest version, I'm confident that the already huge popularity of the Stellarvue Nighthawk series is about to increase even more.
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Nebulosity
A certified "Best Buy" for image capture and processing
A note from the editor: This article includes screen images that demonstrate various features of Nebulosity. Unfortunately, our print format is ill suited to reproducing the fine detail necessary to full appreciation of each screen shot. We wish to remind you that your current subscription to ATT includes ready access to the online version of every issue of the magazine. All images in this and the other articles of this issue are available there in high-resolution PDF. There you will also find additional screen images that compliment this article. By David Snay
Readers of Astronomy Technology Today are likely familiar with Craig Stark of Stark Labs. He has previously contributed to ATT, describing the ins and outs of PHD, the autoguiding software that is available free on the Stark Labs web site, www.starklabs.com. He is also the author of Nebulosity, a program that provides image capture as well as pre- and post-processing features for the very small price of $45. Nebulosity specializes in performing data capture and image pre-processing functions, such as alignment and stacking, with very high precision. It can also perform much of the fine-tuning functions required to produce a high quality image from all those photons you worked so hard to capture. Nebulosity uses 32-bit precision for all its functions in order to achieve more accurate integration of sub-exposures as well as calibration with dark, bias and flat frames. In addition to providing a wide array of features, Craig has done a masterful job of documentation. I have used several processing packages and I can say without hesitation that the information in the help sections of Nebulosity is far superior to anything I have seen anywhere. The education on dark, bias and flat frame usage alone is worth the price of admission! Craig has also produced some very helpful “how-to” doc-
uments that reinforce the information in the help sections extremely well. These documents are available on the Stark Labs website as tutorials within the Nebulosity section. The interface to Nebulosity is very clean and simple. All the tools you will need for image capture (and nothing you will not need) are on the main window and easily understood. Critical controls are located along the right side of the frame and there is also a status bar along the bottom that tells you what is going on while leaving the overall screen uncluttered. A quick tour through the documentation will make the screen layout even easier to understand, as well as reveal changes you can make to the appearance, but you can certainly start without any help on your first night out. Read the section on the Exposure panel and you’ll collect even better data that is easier to manipulate later. Nebulosity supports the FITS file format very well. All the data that I’ve grown accustomed to finding in the FITS header is still there. I am especially happy to find that both exposure length and CCD temperature are recorded, making it much easier for me to pick the appropriate dark frames for later use. The set of features within Nebulosity is far too extensive to explore in the context of
one article. Besides, that would be tantamount to duplicating the help provided with the software. However, it is appropriate to review some of the features you’ll likely use most frequently. I’ll start with data capture tools and then move to image processing tools. Data Capture Craig has put together a set of tools that is very effective for data capture, while keeping to his desire to keep things simple to use. I used the full set to make an image of M48 on February 2, 2008, while the moon was shining brightly. Select the Frame and Focus button in the Capture palette and you’re presented with the screen shown in Image 1 on the next page. The first time I selected this option I was thrilled to see the crosshair. I have been struggling for more than two years to center images with the software that came with my imagers. The software I’ve been using doesn’t show the entire image in the preview window (I still don’t know why that is true.). To learn that Craig had the answer all this time was both a relief and humbling, as a little exploration on my part would have yielded this solution long ago. Now all I have to do is specify a short exposure duration, select this tool, and compose the Astronomy TECHNOLOGY TODAY
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NEBULOSITY IMAGE CAPTURING AND PROCESSING
Image 1 – Frame and Focus Interface (Note the Crosshair Feature in the Main Screen Section)
image as I desire. Once I had the cluster centered the way I wanted it, I exited the Frame and Focus tool and moved on to the Fine Focus tool as shown in Image 2. When you first select this tool, you need to specify a star to use for focus adjustment. In this image you
can see that the star I selected is still out of focus, even though it appeared to be in focus in the Frame and Focus window. As you improve focus, the star image will improve and the values shown will rise. There is a detailed description of the meaning of these values in Craig’s documenta-
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tion. You can use your eye, the values, or both, to fine tune your focus adjustment. Once I had the image focused properly I then selected the Directory button in the Capture palette to specify where to save all files. I then entered a name to use for the prefix for all files for the next Capture Series. I was almost ready to start the series. One quick preview of my desired exposure duration and I would be ready to fire away. The status bar along the bottom of the window indicated that Nebulosity was taking one image in a series of one image, each at 120 seconds duration. It also told me that the percentage needed to complete the current image capture had been accomplished and that it was actively capturing data. If the series were complete, then it would have shown “idle” rather than “capturing.” Everything looked good at this point so I decided to go ahead and let it capture 15 exposures of 120 seconds duration each. After making that change, the status bar revealed the details of that longer series. Since working on this report, I have learned that I can change the display to show the current temperature of the CCD chip along the status bar, if that data is supported by the camera. That will prove very useful for ensuring the use of the correct dark frame. When capture was complete, the status indicator changed from “Sequence acquisition" to “Sequence done”, and “Exposing” and “Capturing" changed to “Idle.” The middle section which showed “Exposing 15% complete” also indicated which file the data was saved to at the end of each exposure. Image Processing The first processing tool you should familiarize yourself with is the Grade Image Quality tool. This tool is ingenious. It measures all images in any given set for clarity against each other and assigns a grade to each of them. It can then either rename the existing files or make new copies with the appropriate names. The naming scheme is straightforward and easy to understand. Average quality exposures will be indicated with a value near "50" in the new name. Poorer quality exposures are assigned lower values and best quality will approach "100."
NEBULOSITY IMAGE CAPTURING AND PROCESSING This tool can remove much of the subjectivity from the process of choosing which exposures to use for the composite. Once you’ve selected the images you want to use, it is time to calibrate them with whatever dark, flat and/or bias frames you choose via the Pre-process B&W/Raw Images or Pre-process Color Images tool. This process couldn’t be simpler. You are presented with a simple pop-up that allows you to perform only the tasks you need. Select an option and you are presented with an interactive window where you can specify the calibration file to be used for the specified task, as shown in Image 3, and then another which will let you specify the light frames to use. Did I already mention that Craig provides an enlightening section on this aspect of the program that is well worth reading before you do any processing of your data? He does a very nice job of taking the mystery out of all three calibration tasks. While I’m on the topic of dark frames, I want to share the results of a test I performed regarding Nebulosity’s control of my Meade DSI-Pro II camera. Amp glow has been a constant problem for all users of this imager. There is a noticeable glow in one corner of all images above a short exposure and I assumed it was just something I had to live with. Well, was I ever wrong! I compared 60-second dark frames taken with the software that accompanied my imagers to those taken using Nebulosity and there is almost no comparison. The amp glow is virtually non-existent in the images taken via Nebulosity! (Comparison images are included at the conclusion of the online version of this article.) I feel it is important to interrupt this demonstration to comment on the quality of dark frame calibration provided by Nebulosity. I have struggled with having dark frames produce the dreaded “brush mark” effect on many of my images ever since I started this wonderful hobby/obsession. I compared the results of my original tools with those of Nebulosity for this set of data. The brush marks were very obvious in my “normally” processed image, but completely absent in the image produced by Nebulosity. This is an amazing improve-
Image 2 – Fine Focus
Image 3 – Select dark frame
ment over the software provided with my camera. If you are using a one-shot color camera, you will need to "Debayer" the images using the Batch Demosaic + Square Raw Color tool before alignment. If you are using a monochrome camera with nonsquare pixels, then you will just need to square them using the Batch Square B&W tool. Both of these tools are found under the Processing tab. The process of aligning and combining these pre-processed data files is also simple.
Nebulosity provides several methods for aligning the individual frames, ranging from simple one star (Translation) automatic alignment, all the way up to two star alignments with each frame fine tuned by the user. My testing showed a significant improvement in the shape of my stars when I used the two star alignment method, Translation + Rotation. This is because the one star alignment method uses only whole pixel adjustments while the two star methods use re-sampling to achieve finer adjustments. If your image frames are of slightly Astronomy TECHNOLOGY TODAY
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Image 4 â&#x20AC;&#x201C; LRGB synthesis
different scales, you can also let Nebulosity track that, resample the frames, and adjust accordingly, to provide image frames of exactly the same size â&#x20AC;&#x201C; just use the Translation + Rotation + Scale alignment option. The scale problem can occur when you use platforms like Schmidt Cassegrain Telescopes that shift the mirror when changing focus, as this alters the focal length of the optical path. You can also use the now familiar Drizzle process to increase resolution of image data. I prefer the Translation + Rotation method as it allows for finer adjustment of each image as well as using two stars for alignment calculations. The process of alignment is extremely easy to use as Nebulosity shows one frame at a time. You indicate the first star to use as a reference point and Nebulosity cycles through all specified images using that star. The star being aligned in the first pass is circled in red and you can choose to verify each image or let Nebulosity assume it is correct without your input past the second frame. Directions are presented in the status bar. When the first pass is complete, you are then directed to select the second star to use for alignment. That star is circled in green and the first star now has a crosshair through the surrounding red circle. If you are using a monochrome imager, you will need to merge your data sets to
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form a color image. Nebulosity provides a very nice LRGB Color Synthesis tool for that which you will find under the Processing tab. With this tool, you can take the Luminance, Red, Green and Blue data sets and combine them to generate a color image. One of the nicest features of this tool is that you can specify the strength of each color in the resulting image, greatly reducing the effort required to balance the colors in later processing. Nebulosity provides the ability to preview the result before exiting the tool, a very useful feature. Image 4 shows how the interface changes as you select the various files. The three color specific boxes start as grey and change to the appropriate color as you identify the file to be used for that color. In this case, I have already specified the red data and am now choosing the green data. Now that you have completed all your pre-processing tasks, it is time for the rest of the work. All astrophotographers realize that the job has really only just begun at this point. No two images are exactly alike, nor do they require the same processing. However, there are some tasks so common that tools to accomplish them are essential in any image processing software package. Nebulosity includes these as a relatively small subset of its large set of tools. Iâ&#x20AC;&#x2122;ll only discuss the most common tools provided and leave the rest to the reader to discover
NEBULOSITY IMAGE CAPTURING AND PROCESSING on the Stark Labs website and in the documentation included with Nebulosity. One of the coolest tools Craig has devised is the Adjust Color Background tool. Using this tool, you are able to rebalance the colors a bit to accomplish most, if not all, of the task of removing background color, usually from sky glow introduced by light pollution. I experimented with this tool for several hours on one of my images and was unable to find settings that worked better than the defaults generated by Nebulosity. I don’t know how Craig taught it to know what to do, but excellent work there! Image 5 shows the result of this tool on my image. The difference is fairly subtle on this image but it really made the rest of the processing easier. DDP was new to me since I do not have MaximDL or any of the other packages that include DDP mechanisms. However, a little Internet research left me believing that this is much like curves in Photoshop. DDP is probably the tool I have used the least in my experimentation to date. However, it did work fairly well on this image. I suspect this is one of those tools that either works great or not very well, depending on the data being processed. The data produced by my imagers did not seem to suit DDP very well. I really like what I can accomplish with curves, so I will probably continue using them for bringing out faint details. Of course, if and when I change imaging platforms, that may very well produce data for which DDP is the appropriate solution. Power Stretch is very similar to the Levels function of Photoshop. The interface is quite different and my extensive background in Photoshop made using this tool initially harder to understand than it should have been. A quick email exchange with Craig and I was much more comfortable with the use of this tool. Much like other software, it pays to work the stretch in several small iterations rather than one big stretch. This lets the 32-bit processing algorithms work to produce the smoothest transitions across the tones within the image. Using this tool, I was able to bring out subtle detail in images of star clusters and bright nebula.
Image 5 – Adjust Color Background
The last image I will share with you is the finish product. Image 6 on the next page shows the results of the previous steps and a very small amount of gradient removal and curves in Photoshop. The preand post-processing features of Nebulosity made the Photoshop process much simpler than it would otherwise have been. Though I did not use them on this image, two more tools that I used quite a bit in my evaluation of Nebulosity are Adaptive Noise Reduction and Tighten Star Edges. Adaptive Noise Reduction is very well implemented. It does a nice job of reducing background noise, particularly in images of star clusters. When used on images that have a nebula in them, the effect can detract from the nebula, which will require further processing to restore the nebula’s impact.
This is not unique to this tool, as all noise reduction methods will reduce the detail within nebulas. Retaining and/or regaining that detail, or reducing the impact of noise reduction, requires a larger, far more complex processing package. Those packages will also make a much larger dent in your wallet. Tighten Star Edges is a very useful tool for cleaning up the stars in your image. It is similar to the complex High Pass Sharpening procedure used by many astrophotographers when working in Photoshop. When combined with Adaptive Noise Reduction judiciously, the results can be that last piece to take your image from very good to excellent. There are a great many tools included in Nebulosity that I have not discussed in this review. Some of them do not apply to
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Image 6 – M48
the monochrome imager(s) I use and others deal with processing aspects I simply have not had time to investigate further. Who Can Use Nebulosity? Nebulosity runs natively on both Mac and Windows platforms, unlike most of its competitors. You will need to download the software package for each platform, but there is only one purchase transaction. The fact that it runs on Mac should be welcome news to many Mac enthusiasts out there looking for a way to capture astronomical images. Many applications support only cameras from one manufacturer. Nebulosity supports image capture on a large list of imagers, including webcams, SBIG, Meade, SAC, Atik, Artemis, Starlight Xpress, CCD Labs, QHY Astro, Fishcamp, Orion, and Canon, on Windows. The current list for Mac is SBIG, Meade, Starlight Xpress, Fishcamp and Canon, with CCD Labs following soon. At this time, there is no support for webcams on the Mac. This is an impressive list of available configurations and Craig is continually adding to it as demand warrants. Conclusions At first, I was looking at Nebulosity as a replacement for my entire current image processing software, which is comprised of Meade’s Envisage, Autostar Suite Image Processing, SGBNR and Photoshop. In hindsight, that is a pretty tall order. That’s also not the goal of Nebulosity. Nebulosity strives to provide us with a tool that, in
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Craig’s words “gets you to the point where you'd pull your spouse or kid over and say, 'Hey, look what I got last night! It still needs to be cleaned up, but look!'”. In my opinion, it does that very well. In typical end-user fashion, I opened up the software and started plunking around the menus trying to make images comparable to the ones I have generated using the aforementioned list of programs. Needless to say, I was less than successful. Then I put on my reviewer’s cap and decided to read the manual. What a novel idea! I know I have commented on the quality of the documentation before, but it is worth repeating. Craig’s document is award winning caliber material. After reading the documentation, I was able to make much better use of the tools. Craig has produced some online examples of how to make best use of the tools which can be found on the Stark Labs web site and should be considered integral to the documentation. In addition to the documentation, there is also an online user group for all of the Stark Labs software located at: http://tech.groups.yahoo.com/group/stark -labs-astronomy-software/. The group is pretty active and Craig is a regular contributor. I wandered through the posts there and it is clear he is genuinely interested in making the product the best it can be. The strength of Nebulosity’s image processing lies in the pre-processing tools. It does a very nice job of producing excellent data files, which can be used to generate astronomical images. If you don’t already have one of the big, expensive packages, Nebulosity can produce full color images that you can be proud of. They may not be the equal of those produced using Photoshop and/or MaximDL, but you will have a significantly fatter wallet. So, after several months of tinkering with Nebulosity, moaning about the lack of clear skies and pestering Craig with endless questions, I have settled on the following general workflow.
Nebulosity: 1. Capture image sub-exposures in FITS format. 2. Calibrate all images with appropriate dark/flat frames. 3. Align/combine each color set and save each in one FITS file. 4. Align the resulting files with each other. 5. LRGB merge them. 6. Adjust Background Color. 7. DDP or Power Stretch – whichever works best for a given set of data. 8. Save the resulting image as 16-bit TIFF file. Photoshop: 9. Import the color image. 10. Perform fine tuning to taste. Nebulosity (if needed): 11. Adaptive Noise Reduction. 12. Sharpen Image_Tighten star edges. 13. Done! Given that Nebulosity is intended to compliment packages such as Photoshop and MaximDL rather than replace them, I would say that Craig has exceeded all expectations. In fact, it will likely replace my current pre-processing software as I feel it does a better job of dark frame subtraction and sub-exposure combination than the software that came with my camera. Have I mentioned how much I like the Adjust Background Color tool? You have to try it if you live in a location with light polluted skies (don’t we all?). I have used Photoshop for more years than I care to admit for production of digital versions of my Fine Art Black & White photographs and it must remain part of my daily routine. Therefore, I will likely continue to use Photoshop for the bulk of my post-processing work. That being said, there are many experienced astrophotographers producing very nice images using Nebulosity from start to finish. In my opinion, Nebulosity can be a very valuable part of any image processing workflow. Combine that with the pre-processing education contained in the documentation and you have a certified "Best Buy" in Nebulosity.
The TMB Optical Paragon 40 Add Some “Wide-Field Variety” To Your Life! By Mike Hardin
They say, “Variety is the spice of life” and any astronomer will tell you a variety of eyepieces will spice up your observing experience. If you’re like me, you spend a lot of time switching out eyepieces, trying to achieve that perfect view of each unique target. If you’re an SCT user, it’s often that elusive widefield view that you seek. Any question about why I jumped at the opportunity to review a new eyepiece? I’m a Schmidt Cassegrain (SCT) fan – it’s hard to beat the versatility of the design offering the light gathering capacity of larger apertures and long focal length to more easily reach high magnifications with the simplest eyepiece designs, all in a very compact package. What the design doesn't easily
produce is the wide-field views necessary for framing many extended, highlight objects. My test base telescope is an “Orange tube” C11 of early 80’s vintage mounted on a late model Celestron CGE. I’ve tried many combinations of accessories to get this widest field possible, including several types of focal reducers. My conclusion is nothing beats a high-quality, wide-field eyepiece alone. This is where TMB Opticals 40-mm 2-inch Paragon “Orthoscopic Super-wide” eyepiece comes in. Let me say right here that I have been a “black box” eyepiece fan for many years – still am. To say I was skeptical about the possible performance of the TMB Paragon eyepiece is an understatement.
The first thing I noticed when pulling the piece out of the box was the weight. Though it measures 4.75 inches long and nearly 2.50 inches in diameter, it only tips the scales at 17 ounces. As a comparison, one of my favorite eyepieces of slightly smaller dimensions weighs in at over 24 ounces. The build quality of the TMB Paragon is immediately evident. The black anodized all-aluminum body is light and good looking. In case you’re wondering why it’s described as “orthoscopic,” since we've come to associate that term as the shorthand label for the classic 4-element “Abbe” design, this time the term is used in its original sense meaning “free from optical distortion.” As my test of the TMB Paragon proved, Astronomy TECHNOLOGY TODAY
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THE TMB OPTICAL PARAGON 40 this is an appropriate description, at least when mated to the very popular SCT. After packing my gear, I headed for the Fakahatchee Strand, a section of Everglades National Park. We here in Southern Florida are fortunate in that the park service has given our local club special permission to use this area after dark. With a million acres of protected land, it’s arguably the darkest site in the Southeastern United States. Look at the dark skies down there and you’ll think you’ve been transported 30 years in to the past. The Milky Way is so bright I swear it casts a shadow of the scope on the ground. The Andromeda galaxy and Omega Centauri are naked eye objects. The downside to this astronomical Mecca is the 8- to 10-foot alligators that live in the nearby lakes - I have been known to have one eye in the eyepiece and the other on the lake shore (well, it
might not actually be that bad, as we haven’t lost an astronomer yet). The other is the limited viewing season lasting only from November through April. Venture into the glades after May and you’ll learn what it means to be “eaten alive” by mosquitoes. After setting up, I checked collimation, which is standard procedure for me. Even though my scope is nearly 25 years old, it has excellent optics and holds collimation very well. Controller in hand I punched in my favorite widefield test object, NGC 884, the Double Cluster, slid in the TMB Paragon 40, and took a look. The first thing I noticed was that the eyepiece had a field wide enough to take in both clusters with ease – not something I’m used to being able to do with the C11. NGC 884 is a great object for testing eyepieces. It gives you a good sense of the field since the two clusters boast an appreciable amount of
separation. Because there are stars clearly visible from one edge of the field to the other, any that are not pinpoints will be readily apparent. I’m happy to say that the only stars that were not perfect pinpoints were at the extreme edge of the field - more than 90 percent of the field was tack sharp! Many of you using high end refractors will probably find that figure to be closer to 100 percent. This is a strong statement to be able to make about an eyepiece costing less than $250. My second and third targets, M42, the Orion Nebulae, and M41, the Beehive, were equally impressive. Even though the 40-mm focal length only yields a magnification of 70X (very low to most SCT fans), I could easily make out the E and F stars in the Trapezium of M42. The Leo Triplet - you guessed it - fit easily in the field. Before the night was over, I observed a number of other Messier objects with the TMB Paragon
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Astronomy TECHNOLOGY TODAY
THE TMB OPTICAL PARAGON 40 - all within the Milky Way providing views of stars all the way to the edge of the field. Each object brought a surprisingly pleasing view, framed nicely in a much wider field than I'd grown accustomed to. Since the ground at this remote viewing site is covered with gravel, I have a morbid fear of dropping expensive eyepieces. Though this may be a small thing, the TMB Paragon provides two 3/4-inch rubber grips separated by another 3/4 of an inch of anodized barrel. When it’s in your hand, you know you have a firm grip and it’s not going to the ground. It also has a tapered cut on the barrel, rather than the more typical setscrew security recess, so it’s not going anywhere once you tighten the thumb screw on your diagonal and yet doesn’t get hung up when you remove it from the compression rings visual backs that have replaced traditional setscrews.
No, I haven’t talked much about field curvature, kidney bean effect, blackout, on- and off-axis performance, pincushion distortion or lateral color. However, I have been an avid observer since age 7 and worked in an optical laboratory for 20 years - I know a good eyepiece when I see one. I think the best thing I could say about the 40-mm TMB Paragon is that I would recommend it to my best friend as well as to you. To me, that’s the ultimate compliment to TMB and Burgess Optical. The folks at Burgess are certainly offering us a high quality, high performance eyepiece for a great price. A conversation with Bill Burgess at the Winter Star Party revealed plans for many more wide-field eyepieces soon to be released by that source. As for the 40mm Paragon, now I have to see if I can talk Bill and ATT into letting me keep for a while.
The TMB Paragons are currently available in focal lengths of 30 mm and 40 mm. Both feature: • Designed by Thomas Back of TMB Optical • Radical new 6 element, 4 group design • Every Air to Glass surface has Multi Broadband coatings • All lens edges are blackened • Coatings have 99.98 to 99.99% transmission (less than 0.02% loss per surface) • Fully internally baffled • Internal spacers have flat anodizing and micro-baffles to reduce reflections. • Flexible two position eyecup • Apparent Field of View (AFOV) of 69o • True AFOV of 68° (there is virtually no magnification increase across the FOV) • Lightweight design • Lettering with a special, red-light reflection • Tapered safety undercut • Oversized locking lens cap
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Deep-Sky Imaging with a Canon DSLR and TMB-130 Refractor By Klaus Brasch
The development of digital cameras in the 1980s triggered a revolution in astronomical imaging comparable to the 1850s when the photographic plate was invented. That, coupled with powerful computer processing methods, now makes it possible for amateurs with small and medium size telescopes to routinely produce images comparable to or better than those obtained at major observatories just a decade ago. High-quality and increasingly affordable digital single-lens reflex (DSLR) cameras have opened up another chapter in this exciting venture. You can now take full advantage of all that digital imaging offers without spending a small fortune on complex CCD cameras, attendant paraphernalia like filter wheels, cooling devices, special adapters, dedicated laptop computers and the like. Canon, Nikon and other manufacturers now market DSLRs in the 5 to 10 Mega-Pixel (MP) range, which produce images of excellent quality and resolution. In addition to more affordable cameras, several outstanding small to medium aper-
ture apochromatic or semi-apochromatic refractors are now available at more reasonable prices than ever before. The TMB-130, signature series is a perfect example. This triplet f/7 apochromat designed by the late Thomas M. Back is a great performer both visually and photographically. Mine is mounted on a Losmandy G-11 along with an Astro Physics 80-mm f/9 guide scope. Most images shown in this article were taken from my backyard observatory near Flagstaff and on field trips to Arizona Sky Village in Portal. Getting Started Like many converts to DSLR imaging, I chose the Canon 20D when it became available three years ago. Its ease of use, versatility and, most important, extremely efficient, low-noise 8.2 MP CMOS (complementary metal oxide semiconductor) sensor made it the camera of choice. Many other versions of this excellent camera are available, including the Digital Rebel, the limited edition Canon 20Da, specifically
designed for astrophotography, the 30D and the latest version, the 10 MP Canon 40D. The full frame 35 mm format EOS 5D and 1D professional models are considerably more expensive. While all models produce pleasing deep sky images, stock cameras lack sensitivity in the red end of the spectrum, particularly the all-important H-alpha and H-beta wavelengths of ionized hydrogen characteristic of emission nebulae. Fortunately this limitation can be overcome through custom modifications like those provided by Astro Hutech which removes the standard IR blocking filter and replaces it with a UV/IR blocking filter that transmits the desired H-alpha wavelength. This can be further coupled with external filters like the IDAS LPS-V3, for enhanced H-alpha H-beta and OIII sensitivity. Current DSLR cameras have an added feature much prized in astronomical imaging; they can be programmed for long exposure noise-reduction. This is crucial, since all electronic sensors are subject to random internal discharges, hot pixels, dark current, Astronomy TECHNOLOGY TODAY
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DSLR DEEP SKY IMAGING thermal effects, cosmic rays, etc., particularly over long exposure times, all of which impact the signal to noise ratio, image quality and contrast. Image Processing While the available selection of image processing software is extensive, my patience and abilities are definitely not and so I try to keep things as simple and manageable as possible. Typically, I take several successive 5-10 minute exposures at ISO 800 and download them later to my computer. Images are usually stacked in RegiStar by Auriga Imaging which is fast and convenient. Starizona’s Levelizer and Zone Mask plug-in filters can be helpful in compressing the tonal range of object like M-8 and M-42, for example, by bringing out faint detail and attenuating bright areas. Panorama Plus by Serif works well for mosaic assembly, and Noise Ninja by Picture Code helps reduce image granularity. All other processing is done in Adobe Photoshop.
Keeping Things Simple What is most gratifying with this combination of optics, camera and processing tools, is that very pleasing deep-sky images of brighter objects can be obtained with cumulative exposure times ranging from 10 to 40 minutes rather than hours. Moreover, since DSLR cameras are stand-alone equipment requiring only DC power to operate, once the telescope is polar aligned and the object is in the field of view, you are ready to go. Though auto guiders are clearly desirable, they are not essential. If your mount is properly aligned and tracks well, simple manual guiding is both fast and easy since individual exposure times are comparatively short. Focusing is always a challenge in astro imaging; however, this is also comparatively easy with current DSLRs. The Canon 20D does not feature “live focusing” like newer models, but a simple 2.5x right-angle finder and a bright star readily accomplish that. After that, a brief test exposure and focus check is all that’s needed. One additional,
essential accessory is a remote switch or timer to avoid shaking the camera or telescope. Results Visually, my favorite eyepieces with the TMB 130 are the legendary Tele Vue 22-mm Panoptic and the 26-mm Nagler Type 5. Both provide stunning wide field views of objects like M31, M42 and the Pleiades under really dark, transparent skies. Nebulosity abounds in the Orion Nebula and brighter stars are enveloped with “haze” in the Pleiades. The dark lanes in the Andromeda galaxy are very distinct and stars are pin points almost to the edge of the field. With any “deep sky” type filter, it’s even possible do glimpse the major dust lanes in the Rosette Nebula. As expected, lunar and planetary views are sharp and contrasty, with virtually no trance of residual color. Photographically at f/7, the TMB 130 performs extremely well. As the uncropped image of the M17 area (Photo 1)
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DSLR DEEP SKY IMAGING clearly shows, stars are sharp to the edge of the frame and only marginally elongated in the corners. TMB does market a dedicated field-flattener for this telescope that extends to the full 35-mm format, if you are willing to pay for it. For considerably less money, Williams Optics sells a fieldflattener 0.8x reducer which lowers the telescopeâ&#x20AC;&#x2122;s f-ratio to about 5.5. If you can live with some edge of field distortion, this economical and considerably faster combination does produce pleasing, albeit slightly imperfect images (Photos 2 and 3). After modification by Astro Hutech, my stock Canon 20D was visibly more sensitive across the spectrum, but particularly with respect to enhanced red sensitivity. This is clearly illustrated in the before and after images on M8 (Photos 4 and 5). Both are unfiltered 8-minute exposures taken with a Tele Vue 101 f/5.4 refractor. Except for minor level adjustments, each image is otherwise unprocessed.
Although the city of Flagstaff has strong light abatement rules, there is still considerable light pollution, particularly as the population increases. The IDAS LPS-P1 also available from Astro Hutech is very effective in filtering out sky glow and the yellow haze of low pressure sodium lighting. Color balance and image contrast are correspondingly increased. This is clearly shown in the side by side images of the Rosette Nebula (Photos 6 and 7). Both are single 8-minute exposures taken with a Tele Vue 101, but are otherwise unprocessed. Even more effective with such emission objects is coupling the modified camera with an IDAS LPSV3 nebula filter (Photo 8). This TMB 130 f/7 image was generated by combining four separate 10-minute exposures into a single picture with Panorama Plus by Serif. Starizona provides two useful Photoshop plug in filters for bright emission nebulae, Levelizer and Zone Mask. Although similar effects can be obtained
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1. M17 and surrounding regions, TMB 130 at f/7, 15-min total exposure. Except where otherwise noted all images were taken with an Astro Hutech modified Canon 20D. 2. Horse Head and Flame nebula, TMB 130 at f/5.5, 20-min total exposure and an IDAS LPS-V3 filter. 3. IC-410, TMB 130 at f/5.5, 20-min total exposure and the LPS-V3 filter. 4. M8, Tele Vue 101 at f/5.4, 8-min unfiltered exposure with a stock commercial Canon 20D. 5. M8, Tele Vue 101 at f/5.4, 8-min unfiltered exposure with the same camera after spectrum enhancement. 6. Rosette Nebula, Tele Vue 101 at f/5.4, 8-min unfiltered exposure taken within Flagstaff city limits. 7. Rosette Nebula, identical conditions to Fig. 6, but taken with an IDAS LPS-P1 filter. 8. Rosette Nebula, TMB 130 at f/7, montage of four 10-min exposures taken with the LPS-V3 filter.
Photo 9
Photo 11
Photo 13
Photo 14
Photo 10
Photo 12
9. Orion Nebula region, TMB 130 at f/7, 22-min cumulative exposure, LPS-
oto 13
oto 14
V3 filter, stacked in Regi Star, processed with Starizonaâ&#x20AC;&#x2122;s Zone Mask filter. 10. Identical to Figure 9, but processed with Starizonaâ&#x20AC;&#x2122;s Levelizer filter. 11. Same as Figure 10 and subsequently processed in Photoshop. 12. IC 443, hybrid image of two separate 20-min exposure taken with a TV 101 at f/5.4 and the TMB 130 at f/5.5 through the LPS-V3 filter and combined in Regi Star before further processing. 13. NGC 2174/75, TMB 130 at f/7, 22-min total exposure with the LPS-V3 filter. 14. Elephant Trunk Nebula, hybrid image of four 10 min exposures each through the LPS-V3 filter, taken with the TMB 130 and a C14 at f/7 respectively. 15. Comet 17P/Holmes, TMB 130 at f/7, Nov. 20, 2007. 16. M45, TMB 130 at f/7, 20 min total exposure, unfiltered. Photo 15
Photo 16
DSLR DEEP SKY IMAGING with Photoshop alone, these two applications are convenient short cuts. Photos 9 and 10 of the Orion Nebula region illustrate what each filter can do. Both pictures were generated from the same series of TMB 130 f/7 images, 10-, 20-, 30-sec and two 10-minute exposures, respectively, combined with RegiStar, and then processed with either the Zone Mask filter (Photo 9) or the Levelizer filter (Photos 10) before any further manipulation. Photo 11 shows the same series of exposures filtered with Levelizer and then further processed in Photoshop for maximum detail differentiation. Photo 12 showing the supernova remnant IC 443 in Gemini is a hybrid of two 20-minute exposures taken on separate occasions with the Tele Vue 101 and the TMB 130 at f/5.5, both through the LPS-V3 filter and then combined in Regi Star. NGC 2174/75 is a beautiful blend of nebulosity and associated open cluster in Orion is shown in Photo 13, a 22-min total exposure with the TMB 130 at f/7
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and the LPS-V3 filter. Photo 14, the Elephant Trunk Nebula in IC 1396, is another hybrid image. It blends two 10-minute TMB 130 f/7 exposures and two taken with a C-14 (also at f/7 with a Lumicon Giant easy Guider); all taken through the LPS-V3 filter. A remarkable amount of detail was recorded in this combined 40 minute exposure of this complex, but dim, star forming region. Photo 15, showing Comet 17P/Holmes as it appeared on November 20, 2007, is a combination of 10-, 20-, 60- and 120-sec TMB 120 exposures at f/7. The comet was at its prime at that point, both in terms of apparent size and structural complexity. The image of the Pleiades, Photo 16, was also taken with the TMB 130 at f/7. This 20-min total exposure with the spectrum enhanced Canon 20D, but without any additional filters, shows that the modified camera is strongly blue sensitive as indicated by extensive
reflection nebulosity recorded. Conclusion Thanks to the development of DSLR cameras with high resolution, low noise CMOS sensors, spectrum enhancement, narrow band pass filters, and user friendly software, high quality deep-sky photography is now within reach of any amateur with a good telescope and solid mount. DSLR imaging is especially rewarding because extremely long exposure times are not mandatory, nor is an excessive amount of support equipment when you image in the field at remote locations. The TMB 130, Thomas Back signature series f/7 apochromatic refractor is an excellent telescope both visually and photographically. It is beautifully machined, easy to handle and can be collimated if required. Equipped with a Feather Touch focuser and smooth focuser rotation mechanisms, it is ideal for DSLR imaging. Priced around $4,000 US, itâ&#x20AC;&#x2122;s also a relative bargain for what you get.
The Stellafane Donation Scope Project Giving Back to Those Who Gave Us Amateur Telescope Making Part 1
By Robert J. Teeter, Jr.
“Build your dream telescope!” That’s what I was told by the powers that be at Astronomy Technology Today (ATT). Pick from among the best of the best components currently available, design the telescope how I see best fit to do so and cut no corners for the finished product. Those are the guidelines I was given in my quest to give back to the telescope making inspiration and the place that has given me some of my most cherished memories of times with my father - Stellafane. Aside from my father, no other single influence did more to instill in me the desire to hone my telescope crafting abilities as has Stellafane. When in 1998 I placed first in the Junior Division, the judges’ recognition of my 8-inch f/6 Dobsonian was a pivotal point in my life, inspiring my subsequent commercial manufacture of nearly five-dozen “Teeter’s Telescopes.” Since that visit to Stellafane in 1998
and my too brief career as a telescope manufacturer, I have moved on to graduate college and to start a career (and will soon be married), but the Stellafane award still hangs proudly on my office wall. Stellafane has also moved on with the addition of its new Flanders Pavilion and continued growth of its outreach efforts. Along with this major infrastructure enhancement, Stellafane has acquired a debt, which it willingly accepted for the benefit of the thousands who attend and benefit from its programs each year. According to Stellafane.Org, “…the dream of the [Flanders] Pavilion (shown above) has fulfilled its promise - providing a large, unobstructed meeting space that is dry, comfortable and can be darkened when needed for presentations.” I consider the tenth anniversary of my introduction to Stellafane a perfect time to do what I enjoy most to give back to Stellafane when it needs it most.
Brainstorming the Project The Stellafane Donation Scope (SDS), as it has become known in the planning stages of this project, began innocently enough with a phone call to the guys at ATT magazine. I called to offer my time and experience to contribute articles on a regular basis and they were hoping to coordinate a scope building project that could be featured over multiple issues. The match was truly written in the stars, if you’ll pardon the pun, and I was officially out of “telescope making retirement.” It was decided that I would build a telescope in the form and fashion of my choice using components donated by various vendors of my recommendation. As the build process progressed, I would detail it through a series of feature articles in this magazine. The completion of the telescope would coincide with the 2008 Stellafane convention (July 31-August 3) where it would be officially presented to the convention’s founding body, the Springfield Telescope Makers. The Astronomy TECHNOLOGY TODAY
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THE STELLAFANE DONATION SCOPE PROJECT culmination of the project would come with an auction of the telescope, with all proceeds going directly to the Springfield Telescope Makers, its Stellafane convention and the Flanders Pavilion Fund. I simply couldn’t say no to a project of this caliber and of this significance. Selecting the Perfect Aperture With an outline of the project in hand and with the help of this magazine’s enthusiastic managers, a list of potential vendors was created. But before we could begin soliciting components, we needed to establish the aperture and focal length. For telescope makers, when someone tells us to envision the dream telescope you would build, many would think first of a 25- or 30-inch Truss-Dobsonian with an f/3-f/4 focal length to keep the eyepiece height reasonable. Certainly, expecting a vendor to donate a primary mirror of that size with a superb figure at sub-f/4 might not be realistic, and for Stellafane to find a ready buyer for such
a large instrument would also prove daunting. Among the goals of this project was producing a series of articles that will be relevant to the broadest range of ATMers and a scope that will be within the purchase power of a similarly large number of enthusiasts. So, I relied on my experience to go back and reviewed what had been my most popular aperture and focal length combinations when I was building telescopes full-time. It was a tie between the 10-inch f/6 and the 12.5-inch f/5. The commonality between the two is their focal lengths, both approximately 61 inches or just about perfect for observers in the 5 foot 5 inch to 5 foot 10 inch height range to use “flat-footed” on the ground when the telescope is pointed near the zenith. It also goes without saying that much of the observing done with telescopes in this focal length can be done seated, a welcome change to those used to larger, longer, telescopes. Furthermore, these two apertures are great for two distinct classes of observers beginners and those with larger instruments.
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A 10- or 12.5-inch telescope will show enough detail, even in mediocre suburban skies, to please any budding amateur. These apertures can also make a great second scope for an observer who already owns a 20- to 25inch Dob and desires a smaller “grab-and-go” instrument that will cool to ambient temperature faster, won’t be as hindered by seeing and can be much easier to assemble and store. Gathering the Components Luckily, our search for just such a primary mirror of this aperture range coincided perfectly with the completion of a premium 12.5-inch f/4.8, 1.25-inch thickness Pyrex mirror that had just become available through Ostahowski Optics. In fact, the first components of the SDS to arrive in my shop were the primary and secondary mirrors crafted by Terry Ostahowski, of Ostahowski Optics (www.ostahowskioptics.com) in Anza, California. Many of you will recognize Terry’s name from his days with Discovery Telescopes.
THE STELLAFANE DONATION SCOPE PROJECT
Unwrapping the remarkable primary and secondary from Ostahowski Optics.
Terry has produced thousands of mirrors, many of which were made available in the 8 inch to 20 inch solid tube and Truss Dobsonians from Discovery. Since his days with Discovery, Terry has gone out on his own, enabling him to devote greater time to each primary mirror and to draw more fully upon his experience of 28 years as a full-time optician. The test data supplied with the primary from Terry, certifies a Strehl ratio of 0.94, Peak-Valley of 0.21 and an RMS of 0.040, while the Peak-Valley of the secondary is 0.10 and the RMS is 0.025. In summary, this is a very good optical set for an f/4.8 that will yield tight star images and clean, detailed planetary images. We thank Terry sincerely for this most generous donation (especially considering the current pricing on Pyrex) that will become the impeccable heart of a very premium instrument. Additional components were delivered shortly after the arrival of the primary and secondary mirrors, including the focuser, truss poles and truss blocks from Moonlite Telescope Accessories (www.focuser.com) in Danville, Pennsylvania. Al and Ron from Moonlite donated one of their dual-speed, triknob, 2-inch/1.25-inch, Crayford focusers that will make achieving perfect focus on this scope a breeze. The fine-focus knob yields an 8:1 reduction and will allow for minute cor-
rections in focus as seeing changes during the course of a given night. The guys at Moonlite were also kind enough to donate their 1.00 inch outsidediameter black-anodized truss-poles and their matching “ball & socket” truss connectors
and blocks. Going to Moonlite for these donations was not a question in my opinion, as I have used its truss poles and connectors on all of the telescopes I have built, including a 16-inch f/6.1 and two 20-inch f/5s whose long focal lengths would tax the strength of
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THE STELLAFANE DONATION SCOPE PROJECT any truss system. The Moonlite components passed these tests with flying colors, showing only the most minimal, yet still certainly acceptable, collimation shifts across these spans. The relatively short focal length of the 12.5” f/4.8 SDS, with its truss poles anticipated to be under 40 inches in length, will allow collimation to be held with rock-solid stability. We thank Al and Ron for their donation of these high quality components. The latest delivery was of the wooden structural components. I had made the decision early in my “Teeter’s Telescopes” career that it would be more beneficial to the final product if I started a relationship with a local cabinet shop to do the rough-cuts and routing work rather than to do it in-house. Usually these mill-shops employ cabinet makers with decades, not just years, of woodworking experience. This includes the know-how to get the most out of their equipment, which usually includes professional grade table-saws, routertables, band-saws and possibly even CNC routers. Essentially, I like to leave the rough-
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cutting to the professionals. That is precisely what transpired on March 29, when I received a call from Specialty Millwork (732.938.4855) in Howell, New Jersey. Richard Feidt, owner and operator, has been supplying the Baltic Birch plywood and the Wilsonart laminates (ie. Ebony Star for bearing surfaces) for all of the telescopes I’ve produced. I knew from the very beginning that this project would be no different. Richard’s attention to detail is evident throughout on the 12.5-inch SDS with his use of rabbet-joints, precise 90-degree cuts and exact machining of the dimensions stipulated in my CAD drawing of the SDS’s components sent to him. We thank Richard for his outstanding work on this project. Vendors that have committed components to this project include StellarCat (www.stellarcat.com) with its ServoCat drivesystem; AstroSky (astrosky.homestead.com/ Astrosky.html) with an 18-point flotation mirrorcell; StellarVue (www.stellarvue.com) with an optical finderscope, mounting brack-
et and illuminated cross-hair eyepiece; Rigel Systems (www.rigelsys.com) with its QuickFinder reflex sight; Shrouds by Heather (www.teeterstelescopes.com/ shrouds/) with a custom Nylon light shroud and truss pole carry case; Denkmeier Optical (wwwdeepskybinoculars.com) with its Denk Binoviewer and Power x Switch package optimized for the SDS; ProtoStar (www.fpi-protostar.com) with a headed secondary mount; Catseye Collimation (www.catseyecollimation .com) with its collimation Comboset; and many others that will be described in subsequent articles of this series. All of the contributed components will be discussed in detail in future installments as I report each stage of the design and construction of the SDS. It should be noted that industry response to the project has simply been overwhelming. Indeed, all companies that we contacted were eager to sign on and more products were offered than we could use in the building of one scope. Such is the industry enthusiasm for history and future of Stellafane.
ASTRO TIPS tips, tricks and novel solutions Grading Sky Transparency with an Automotive Tool By Greg Hunter I have tried for a long time to find an objective way to judge seeing and transparency so that I can tell my friends just how good conditions were on the night they chose to sleep in. Over the years I noticed that on nights when the sky is exceptionally clear, there is almost no humidity in the air - it cools down really fast and seeing is usually bad. On the opposite end of the scale, I have noticed that the best seeing is usually just before the sky clouds up or at dew point – but transparency is horrible. Sky Conditions Scale Transparency Temperature Difference 10 60 degrees 9 55 degrees 8 50 degrees 7 45 degrees 6 40 degrees 5 35 degrees 4 30 degrees 3 25 degrees 2 20 degrees 1 15 degrees
So, it seems transparency and seeing are all about humidity. I theorized that since the night sky should be extremely cold, then the less humidity in the air the bigger the difference between sky and ground temperature. But how to measure humidity two miles straight up? I found a cheap infrared heat sensor such as sold at most auto parts places so you can tell how hot your muffler is before you burn yourself on it. The device I bought measures temperatures up to 250°F and down to minus 40°F, sufficient to be able to know where you are on the scale of 1 to 10. After some monitoring I came up with my own scale for sky conditions. Here’s how to find yours in three easy steps: 1 - Point the infrared sensor straight up at the sky (they have a wide field of view, so pick a part of What to Expect the sky where no trees are located). Record the temperature. 2 - Point Exceptional transparency - bad seeing. the sensor at the ground Very good transparency. Good to average transparency. (pick a spot that's not under Average transparency. a tree or other covering, as Below average transparency. this will alter your Borderline transparency - work on alignment results). 3 - Record the Very stable seeing - clouds start to form. Cloudy - go home. difference in the two Cover your scope - it might rain. measurements. Get an umbrella - if itʼs not raining, it will! Try it!
Submit Your Astro Tip! Astronomy Technology Today regularly features tips, tricks, and other novel solutions. To submit your tip, trick, or novel solution, email the following information: • A Microsoft Word document detailing your tip, trick or novel solution. • A hi-resolution digital image in jpeg format (if available). Please send your information to tips@astronomytechnologytoday.com
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