Production Process
course documentation Rujuta Thakurdesai M.Des Sem 1 Graphic Design 2016
Rujuta Thakurdesai M.Des. Graphic Design 2016 Sem I
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Acknowledgements The course ‘Production Process’ has been an important module in our learning of Graphic Design and it involved sincere effort of our faculty in getting us acquainted to the various aspects of production process. I would like to express my gratitude towards our anchor for this module Dr. Tridha Gajjar for guiding us in the correct directions throughout the course and Mr. Bharat Suthar for his extreme patience and effort in helping us gain important insights in the world of printing. I would like to thank all the technicians of Print Labs, NID, for constantly helping us know about the practical aspects of Production process.I am also grateful for the help, support and teamwork of my fellow students in the work hereby documented.
Objective To expose the students of graphic design to the basic fundamentals of printing technology. The entire process from the finalisation of the design to the artwork to the pre-press, nature of printing and post printing stages shall be dealt with. We would also be probing into other related but critical issues such as kinds of paper, specifi cations, costings, etc. The idea is to understand how your graphic design is going to be eventually reproduced in numbers, so that you can effectively use the knowledge of limitations and advantages of each process more meaningfully and creatively. To understand the most appropriate printing techniques To understand colour mixture To understand the method of achieving quality control input
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Introduction Printing is a process of production of type and image typically with ink on paper using a printing press. It is often carried out on a large scale as an industrial process and is an essential part of publishing.
Unconventional Non impact printing aka. Masterless printing hence new image has to be produced for each reproduction and cost is same for each print electrography, ionography, magnetography, inkjet, laser, thermography
Conventional Impact printing which is printed with one master. One time cost of the plate hence affordable for mass printing. Screen, gravure, lithography, offset, dry offset, flexography
Types of printing mapped chronologically
Invention of paper in China
Conventional Processes 105AD 4
Process The process of printing involves 3 major phases in the production.
Making the original Pre media
Pre press Series of steps by which an idea or an image is transferred onto an image carrier (master)
Press The actual printing operations where master prints on the substrate.
Original
Repro preparation Film Plate making Printing plate
Printing process Printing sheet
Post press Assembly of the printed material, binding and finishing operations.
Print finishing
Woodblock printing
Moveable type
Printed product
carved wooden block masters
Hot Metal Type each character is cast separately and placed together to make a block of text
200 AD
1040 AD 5
Gravure is a type of print which has the printing area is engraved on the surface a drum with image printed in the form of multiple grooves which holds the ink and transfer it to the substrate. It is used for commercial printing of magazines, postcards, and corrugated (cardboard) product packaging. Gravure printing is characteristically used for long run, high quality printing producing a sharp, fine image.
Doctor blade is a thin metal blade that clears excess ink from the non-image areas of the cylinder
Gravure cylinder
Paper
45 degrees Gravure cylinder
Ink fountain
It is the 2nd oldest form of printing. Which gives Long lasting prints. The plate making process is expensive The plates are made by mechanical (engraving) or chemical process (acid etching) Intaglio uses variable depth of the cell to print different intensity of colours The ink used in this printing is thinner compared to other processes.
Intaglio/ Gravure Printing drum based printing
1430 6
Recessed plate
Platen Press
It is the oldest type of printing in which metal movable type (Invented by Gutenberg) is used and relief blocks of zinc for image. Elements are assembled together to create a form, which is locked inside a metal frame called chase. Traditional press had following characteristics •Composing stick •Normal leading •120% of the type size •1inch= 6 pica=72 points •1 pica = 12 points •Keyboard showing 7 alphabets layout •EM scale – Line of individually cast monotype character composition, or typesetting, is the stage where pieces of movable type are assembled to form the desired text. The person charged with composition is called a “compositor” [or typesetter], setting letter by letter and line by line
Cylinder Press
Cylinder Press
Letterpress Type of relief printing
1440 7
Lithos in Greek means stone, as when it started the printing was done with stone. It was invented by Aloys senefelder. Image and non-image area are at the same surface planograpic level, but with different chemical and physical surface properties. Based on the principles of Hydrophylic and Hydrophobic surfaces. Water and greese is applied to the porous surface. As inks are greese based the hydroplylic areas dont hold ink. Based on this process the Offset Printing Process was developed.
Lithography Chemical process
1796 8
water damper Ink fountain
Plate Cylinder
Printed paper
Impression Cylinder
Plate Cylinder Anilox roller
Ink fountain
It is a technique of relief printing where rubber plates are used (now photopolymer plates) Substrates are usually non porous like plastic.Suitable for thin flexible soft and hard films, used for printing on cellotape used frequently for packaging. Motelling can be avoided in flexography as rubber plate is used. In flexography the content that needs to be printed is on a relief of a printing plate, which is made from rubber. This plate is inked and that inked image is subsequently transferred to the printing surface. The process can be used to print on paper as well as plastics, metals, cellophane and other materials. Flexo is mainly used for packaging and labels and to a lesser extent also for newspapers.
Impression Cylinder
1. Fountain roller The fountain roller transfers the ink that is located in the ink pan to the second roller, which is the anilox roller. 2. Anilox roller This is what makes flexography unique. The anilox roller meters the predetermined ink that is transferred for uniform thickness. It has engraved cells that carry a certain capacity of inks that can only be seen with a microscope. These rollers are responsible to transfer the inks to the flexible-plates that are already mounted on the Plate Cylinders. 4. Plate cylinder The plate cylinder holds the printing plate, which is soft flexible rubber-like material. Tape, magnets, tension straps and/or ratchets hold the printing plate against the cylinder. 5. Impression Cylinder The impression cylinder applies pressure to the plate cylinder, where the image is transferred to the substrate. This impression cylinder or “print Anvil� is required to apply pressure to the Plate Cylinder.
Advantages -wider range of inks which are water based rather than oil based inks -faster drying and, as a result, faster production -lower costs
Flexography Flexible surface
1873 9
Offset printing is the most commonly used method today, and has many advantages over other forms of printing, especially when we need high and consistent image quality. An image is transferred to a offset plate which is chemically treated so that only image areas (such as type, colors, shapes and other elements) will accept ink. Water and ink is applied to the plate. Because of the chemical treatment, ink only “sticks� to the image areas, which reject the water. Areas without images reject the ink. The images with ink are transported then from the plate to the surface of blanket. The task of printing blankets that are made of special multi-layer rubber is to convey the image or illustration to the paper and this is repeating on every paper that passes through the printing machine. When we print full color job the paper is overprinted four times on four separate printing units with different colors.
Inking unit Damping Unit
Plate Cylinder Rubber Blanket
Impression Cylinder
Advantage Inexpensive High quality Widely available Able to print on a variety of papers and boards Blanket stops the abrasive surface of the paper from wareing off the printing plate Able to print on both sides of the paper in one pass PRINT RUN is the number of copies of a book, magazine, etc. printed at one time. Long- 1 lack copies to 3 lack copies Medium- 1 lack copies Short run- 10,000 copies
Offset printing Chemical process based on Lithography
1875 10
Antipathy of greese and water
Body Beard set
Block Block ht 0.918 inches
This method injects molten type metal into a mold that has the shape of one or more glyphs. The resulting sorts and slugs are later used to press ink onto paper. Two different approaches to mechanising typesetting were independently developed in the late 19th century. One, known as the Monotype composition caster system, produced texts with the aid of perforated paper-ribbons, all characters are cast separate. These machines could produce texts also in “large-composition� up to 24 point. The other approach was to cast complete lines as one slug, usually comprising a whole line of text. Of this system there have been at least 5 different enterprises: Linotype, Intertype Corporation, the Typograph, produced in Germany The Monoline, a very basic machine The Linotype and similar Intertype machines came out with paper tape and electronic automation near the end of their life cycles that allowed for the news wire services to send breaking news to remote newspaper offices for prompt setting into late editions
Face Shoulder Pin Mark
Stem Knicks
Groove
Hot metal type setting Impact printing process
1884 11
Screen printing is the most versatile of all printing techniques, as it can print on any surface in various orientations, today nylon mesh is used thickness of the ink can be increased which is not possible in any other printing method. Wider range of ink and dye is used. The type of fabric used to create a screen depends on the requirement Does not produce high quality Ink takes more time to dry -Plate consists of a fine mesh such as nylon, polymer or wire mesh -Non printing elements of the mesh are blocked by a coating i.e. stencil -Screen plate is covered with ink and a squeeze is passed over it -The pressure of the squeeze makes the ink pass through the open areas in the mesh and reach the substrate lying below -Mesh is based on threads per inch, which can range from 25 to 500 -Special inks such as glitter, UV e.t.c come with instructions such as the thread count and the drying time -PVC ink is used to print on Plastic surfaces and now also on normal paper. PVC is the preferred choice of ink as it quick drying.
Screen Printing Based on stencil technique
1907 12
Squeezee
Mesh Masking Screen coating is used to print the non-image area which prevents the ink from flowing through those holes. This is suitable only for 100 prints Photochemical Direct Screen Coating + Ammonium bichromate makes the screen photo sensitive. It is applied on the screen using the coater, which is a steel appliance which is either semicircular or V shaped. *Degrease: To remove dust and oil marks
Steps to prepare a screen 1.Degrease 2.Wash with water 3.Dry in the driers 4.*do not touch with hands post drying* 5.Expose the screen to hard light 6.Any type of light can work, but harder the light faster the screen is ready 7.Wash in water 8.Print Direct / in-direct Direct Makes use of a croamlin sheet. Chromelin Is not naturally photosensitive, in order to use the sheet ammonium bi chromate needs to be added. Post this the plate is ready for exposing to make a screen.Chromelin makes sure sharper lines are produced in a normal screen as parts of the grid where in small parts inside a grid is left fall off or gwet washed off creating a jagged edge. Indirect A naturally photosensitive sheet is used which id first exposed to the positive and developed and then pasted on to the frame. Sqeezee 1. Square edge basic printing 2. Rounded edge more ink deposition 3. U shaped for Heavy ink deposition used for textile 4. V shape for texture surface 5. Bevel edge for printing used on Glass 6. Ceramic surface
Squeezy detail Mesh
Image Carrier
Build up tabs
Register guides
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Offset Printing
Screen Printing
This poster was printed as a group assignment to gain a better understanding of offset printing and screen printing. The design of the poster allowed us to see how the images and text gets printed in different forms. The poster talks about the Heidelberg offset printing machine. We first chose one colour for printing in offset press and decided the second colour to print over the first one by screen printing. The experience was very exciting and informative and we got to witness the nitty-gritties of the process.
Poster Printing 14
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Image (face down) Glass Electrically charged drum Powder drum
Invented by Chester Carlson in 1937 and developed by Xerox Corporation. Artwork is placed face down on a glass plate and is illuminated by fluorescent light which travels the length of the image. The reflected images is directed through the lens to a electrically charged drum. This charge leaks away where light from the image fallen on the drum. A resin based powder called toner is attracted to the image areas This pattern of toner is transferred to the sheet of paper, where it is fixed fused by heat. Laser copier works like combined scanners and image setter by the scanning the image on to an electrostatic drum.
Xerography
Unconventional Processes
Electro photography/ Electrostatic Printing
1938 16
Formerly collotype was finest technique of the reproduction of paintings. In this process, a glass plate is first coated with light sensitive gelatine solution. Then exposed to continuous-tone negatives. Then soaked in glycerine, which is absorbed most in the non-hardened areas. Hardened area accept the ink, and the plate can be used to print a few thousand copies of the positive image. {Material of the paper is photo sensitive which helps achieve gradation in colour without the use of halftone or breaking the image down to dots} Used by painters to reproduce their paintings Where ever the light passes through the negative and meets the gelatine, the gelatine cracks, the grey is produced as the parts where the light intensity is low cracks less and the parts where in the light intensity is high cracks more. Post cracking the plate is exposed to glycerine which washes off the gelatine and feathers the cracks which creates the smooth transition of the greys. Reticulation – phenomenon of cracking the master. Once glycerine is applied, the same process of lithography is followed.
Print finishing process that produces glossy raised lettering by funding thermographic powder to the print. The text is first printed and then is coated with fusible resin powder.When passed under the IR, resin pigment is fused to give hard raised image. Thermography is print finishing process that produces a glossy, raised lettering by fusing thermographic print. Not appropriate for printing halftones or large areas of colour, which are likely to have a pitted or mottled appearance Edges of the text is not sharp and clear Not appropriate for halftones
Collotype (Photo Gelatin)
Thermography
Screenless planographic technique for high quality reproduction
Print finishing process
1856
1875 17
Substrate In an inkjet printer the image that needs to be printed is created by small droplets of ink that are propelled from the nozzles of one or more print heads. Inkjet devices can print on a wide range of substrates such as paper, plastic, canvas or even doors and floor tiles. Inkjet printing is used a lot for posters and signage. It is also economical for short run publications such as photo books or small runs of books. In-line inkjet printers are sometimes combined with other types of presses to print variable data, such as the mailing addresses on direct mail pieces.
Inkjet Printing Digital non impact printing
1951 18
Spray nozzle
Diods
Gutter
Ink pump
It produces high-quality text and graphics and moderate-quality photographs. It repeatedly passing a laser beam that projects an image of the page to be printed onto an electrically charged, selenium-coated, rotating, cylindrical drum (or, more commonly in subsequent versions, a drum called an organic photoconductor). Photoconductivity allows the charged electrons to fall away from the areas exposed to light. Powdered ink (toner) particles are then electrostatically attracted to the charged areas of the drum that have not been laser-beamed. The drum then transfers the image onto paper (which is passed through the machine) by direct contact. Finally the paper is passed onto a finisher, which uses intense heat to instantly fuse the toner/image onto the paper.
Laser Toner
Heat cylinder Impression cylinder
Laser Printing Electrostatic digital printing process
1969 19
Letterpress -The edges of the text will show ink squash due to heavy pressure -Due to heavy pressure, at the back of the paper slight indentation will be seen -Ink intensity is higher compared to offset printing, due to direct transfer of ink
Offset -Impression will be even in text and halftone -Lines and text will be sharp and has clear outlines -Solid colours are evenly inked -Better text reproduction than gravure
Gravure -Edges of the text will not be sharp -Shows jagged edges -Reproduction of halftone dots is very precise because they are in offset printing -The image quality is better than that achieved with offset printing
Screen -Due to heavy ink deposition, it shows slightly raised impression. -Ink intensity is also high and even -Text is relatively blurry and low compared to Offset
Identification of Major Printing Processes 20
Types of Originals Line Art These are images that contain only black and white pixels. A line drawing is any image that consists of distinct straight or curved lines placed against a background, without gradations in shade (darkness) or hue (color) to represent two-dimensional or threedimensional objects. The lines in a piece of line art may be all of a constant width (as in some pencil drawings), of several (few) constant widths (as in technical illustrations), or of freely varying widths(as in brush work or engraving).
Continuous tone This is an image in which colors and shades of gray smoothly merge into the neighboring colors or shades, instead of producing distinct, sharply-outlined areas of color or shade. A continuous tone image is one where each color at any point in the image is reproduced as a single tone, and not as discrete halftones, such as one single color for monochromatic prints, or a combination of halftones for color prints. The most common continuous tone images are digital photographs every single pixel of which can take a continuous range of colors depending on the quantity of captured radiance.
Pre - press 21
Halftone process, in printing, is a technique of breaking up an image into a series of dots so as to reproduce the full tone range of a photograph or tone art work. Breaking up is usually done by ascreen inserted over the plate being exposed. The screens are made with a varying number of lines per inch.
How it Works? -Halftone will create an optical illusion that makes the tiny halftone dots appears as they are blended into a smooth continuous tone seen by the human eyes -The more dots per inch smaller the dots and smoother and more evenly blended the final image appear -The lower the LPI the larger and more obvious the halftone dots in the printed image
Density is the level of darkness in a negative, positive film or print. Measurement of density is called densitometry. The optical instrument used to measure the intensity of tone of film or reflection copy as well as the ink reading of the printed copy is called Densitometer. Density range is the difference between the highest and lowest density of a photographic image.
Halftone 22
What is a screen? Unlike Photography, difference in lightness cannot be directly reproduced in printing. Printing paper either has colour or none at all, meaning there is no such thing as ‘a little colour’. However screens trick the human eye into thinking that it sees difference in lightness. In a black and white image, different grey tones can be simulated by printing a number of small dots larger or smaller. These small dots are arranged at regular intervals in a grid structure that is called a screen Glass screen Halftone print becomes a dot while the gird is square because of the diffraction theory Diffraction: The process by which a beam of light or other system of waves is spread out as a result of passing through a narrow aperture or across an edge, typically accompanied by interference between the wave forms produced. Screen Ruling: Number of lines per inch of screen known as screen ruling. More the number of lines per inch of screen, the smaller the average dot produced. The use of finer screen, produced more detail in the picture, than the coarse screen. Three variables help decide what screen ruling to use for halftone photograph. -Normal viewing distance - The LPI is determined by the viewing distance. -Process of reproduction -Type of base material Screen Angle: The method of aligning row of halftone dots at different angles to avoid moire pattern, in multicolour printing, moire pattern is created when overlapping screens create then appearance of unwanted lines and patterns Conversion of continuous tone image into ink printable image using halftone screen. When the job is printed in single colour the job is printed at 45 degree.Black is always printed in 45degree. In digital process halftone dot is generated in image setter in specified LPI, where physical screen is not required While converting a photo to a halftone, a standardised greyscale is used to match colours
45 0
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15 0
A
75 0
B B
A A A B
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Screening Technology FM ScreeningFrequency modulation. used for continuous tone image. In FM Screening dots are placed randomly so no moire pattern is created. At 300 dpi: bigger dots are oriented and at 600 dpi: finer dots are printed. Size remains same as halftone but number of dots increase. Measured in Microns. Inkjet printers : Dot randomly placed Laser printer : Moire Pattern is created. The following definitions affect the result (quality) of the final output: Screen Ruling - the number of dots per linear inch measured along the axis of each row. Screen Angle - defining the angle of the axis. Screen Dot Shape - generally Elliptical, Round or Square. Staccato 36 is the most common FM screen u sed in Newspaper The highlight dot measures 42.4 microns which is equivalent to a 2% dot at 85 LPI 3% dot at 100 LPI 4% dot at 125 LPI 6% dot at 150 LPI AM ScreeningAmplitude modulation. The size of the dot changes according to colour intensity.
Halftone 24
Halftone at 45 degrees
Moire Pattern created
Dot Shape
There are three halftone dot shapes generally used today. The most common is the Elliptical Dot that gives smoother midtones especially when printed on a Litho Offset machine. By joining the dots below 50% on one axis only and then above 50% on the other axis, the change in this important tonal area appears less harsh than is otherwise experienced with the Square Dot. The Round Dot also suffers from a fairly harsh transition as the dots get larger and start to touch, but this happens at a higher percentage than the square dots 50% point, and tends to reduce the visual effect slightly because it is in the darker areas of the image. The method of printing, the plate type and product surface can all influence the preferred dot shape. i.e. Screen Printing, Flexo Printing, on plastic, tin, cardboard etc
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Colour is the visual perceptual property corresponding in humans to the categories called red, blue, yellow, etc. Color derives from the spectrum of light (distribution of light power versus wavelength) interacting in the eye with the spectral sensitivities of the light receptors. Color categories and physical specifications of color are also associated with objects or materials based on their physical properties such as light absorption, reflection, or emission spectra. Available color systems are dependent on the medium with which a designer is working. When painting, an artist has a variety of paints to choose from, and mixed colors are achieved through the subtractive color method. When a designer is utilizing the computer to generate digital media, colors are achieved with the additive color method.
Colour 26
Subtractive Color(CMYK Model) When we mix colors using paint, or through the printing process, we are using the subtractive color method. Subtractive color mixing means that one begins with white and ends with black; as one adds color, the result gets darker and tends to black. The CMYK color model (process color, four color) is a subtractive color model, used in color printing, and is also used to describe the printing process itself. CMYK refers to the four inks used in some color printing:cyan, magenta, yellow, and key (black). Though it varies by print house, press operator, press manufacturer, and press run, ink is typically applied in the order of the abbreviation. The “K” in CMYK stands for key because in four-color printing, cyan, magenta, and yellow printing plates are carefully keyed, or aligned, with the key of the black key plate. The CMYK model works by artially or entirely masking colors on a lighter, usually white, background. The ink reduces the light that would otherwise be reflected. Such a model is called subtractive because inks “subtract” brightness from white Additive Colour (RGB Model) If we are working on a computer, the colors we see on the screen are created with light sing the additive color method. Additive color mixing begins with black and ends with hite; as more color is added, the result is lighter and tends to white. The RGB colors are light primaries and colors are created with light. RGB refers to Red, Green and Blue Red, Green and blue are primary colours of light. and they cannot be produced by the combination of any other colours. When combined full in full strength it will produce white light. Hence the name ADDITIVE COLOUR. The RGB color model is additive in the sense that the three light beams are added together, and their light spectra add, avelength for wavelength, to make the final color’s spectrum. Zero intensity for each component gives the darkest color (no light, considered the black), and full intensity of each gives a white. Percentages of red, green, & blue light are used to generate color on a computer screen
Colour Models 27
Gamut A gamut is the range of colours that a colour system can display or print. The spectrum of colours seen by the human eye is wider than the gamut available in any colour model Among the colour models used in Photoshop, L*A*B has the largest gamut. Typically RGB gamut contains the subset of these colours that can be viewed on a computer or television monitor (Which emits red green and blue light) Therefore some colours such as pure cyan or pure yellow cannot be displayed accurately on a monitor. CMYK gamut are smaller, consisting only of colours that can be printed using process colour inks When colours that cannot be printed are displayed on screen they are referred to as out of gamut colour that is outside a CMYK gamut
Colour Separation Prepress changes the original image into 4 or more films or printing plates.This is called color separations. Each film or plate represent separate colors. Plates made from each separation could be printed with black or any other color. The four halftones are printed in B, C, M, K register with each other using the color sequence that they stimulate original full-color image.
Colour Correction Color grading is the process of altering and enhancing the color of a motion picture, video image, or still image either electronically, photo-chemically or digitally. The photochemical process is also referred to as color timing and is typically performed at a photographic laboratory. Modern color correction, whether for theatrical film, video distribution, or print is generally done digitally in a color suite.
Colour 28
Trapping Trapping is a term most commonly used in the prepress industry to describe the compensation for misregistration between printing units on a multicolor press.This misregistration causes unsightly gaps or white-space on the final printed work. Trapping involves creating overlaps (spreads) or under laps (chokes) of objects during the print production process to eliminate misregistration on the press. Trap on a press is the ability of a printed ink to accept the next printed ink compared to how well paper accepts that ink. Registration is when you line all your printed images up over one another.
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Spot Colour The inks which are already mixed and readily available inks or if the designer specifies any shade, the printer can mix the required color are called spot color. Spot colors can be specified from a color matching system or a hand mixed to match a color submitted by the designer. In this rocess, the printing is done using pre-mix shade of ink. This is used when certain specific tone is needed, and achieving that becomes difficult using the 4 colour printing method. Spot colors can be produces in a wider and more vibrant range of colors than the traditional four color printing. Special characteristics like metallic and fluorescent s can also be done.
Duotones
Duotone is a halftone reproduction of an image using the superimposition of one contrasting colour halftone (traditionally black) over another color halftone. This is most often used to bring out middle tones and highlights of an image. The most commonly implemented colours are blue, yellow, brown, and red. Due to recent advances in technology, duotones, tritones, and quadtones can be easily created using image manipulation programs.
Four Colours
This is the process whereby illustrative material is reproduced in colour on the printed page. The fourcolour process is used to produce a complete range of colours. In this process, the material to be reproduced is separated into three basic colours plus black, which is used for density and image contrast. The basic colours are cyan, a combination of blue and green; magenta, a combination of red and blue; and finally yellow and black.
Hexachrome
Hexachrome is a high-fidelity 6-color printing process which uses enhanced CMYK inks along with an orange and green. This system Provides a wider gamut. Brighter greens, orange, more vibrant purples, and truer skin tones can be obtained using Hexachrome. Color range and accuracy are improved as compared to traditional four-color process. Standard CMYK inks appear dirty when compared to the more vibrant Hexachrome cmyk.
Colour Reproduction 30
Desktop Publishing (also known as DTP) combines an Input device, personal computer, page layout software and a printer to create publications on a small economic scale. Users create page layouts with text, graphics, photos, and other visual elements using desktop publishing software such as Adobe Pagemaker, Quarkexpress, Adobe Indesign. It began in 1985 with the introduction of Pagemaker Software from Aldus and the Laserwriter printer from Apple Computer. The ability to create WYSIWYG page layout on screen and then print pages at 300 ppi resolution was revolutionary for both the typesetting industry and personal computer industry. Page Maker was the first desktop Publishing program introduced in 1985 by Aldus Corporation initially for Apple Macintosh. Caliberation The simplest calibration methods involve adjustments to the Contrast and Brightness settings of your monitor. Commonly done with device that change color frequently like monitors and printers. An intermediate method uses special software to calibrate your printer, scanner and other devices so that what you see on-screen, what you scan and what you print all look the same.
Colour Profiles The profile is a colour space that was previously measured and a set of instructions for the gamut mapping that is to be carried out. There are different types of profiles. Device dependent profiles such as printer, scanner, monitor profile. They each describe the colour space that can represent the device.
Vector & Raster Vector graphics Mathematical relationship between point and the paths connecting them to create an image. Smooth when scaled to any size. Best suited for type, line art and illustrations Adobe illustrator and Indesign kind of tools Raster graphics Also known as bitmap Grid of individual pixels where each pixel can be different color or shade Edges get jagged if scaled up. Suited for photography and images with shading Adobe photoshop kind of tools
Desktop Publishing 31
CCD Based Flatbed Scanner Most versatile and popular image capturing device Lesser density range -CCD will not see all the shadow detail,in contrasty, transparencies, not reproduce these areas fully. Scanning resolution ~ 5500 dpi for true optical resolution Spec dust lying on a CCD sensor may cause streaks across the image in the scan direction
Moving laser
Drum Scanner Photomultiplier tube technology (PMT) Capable of registering wide density range Screen resolution ~12000 dpi optical resolution Small dust situated on the scanner sensor will be proportionately small in size so that its effect will be insignificant Costlier than CCD Expert interference required for usage Only supports flexible originals
Data Input Devices 32
Stationery laser
Bleed – Bleed is a printing term that refers to printing that goes beyond the edge of the sheet after trimming. The bleed is the part on the side of your document that gives the printer that small amount of space to move around paper and design incon¬sistencies.
Crop Marks – A set of horizontal and
vertical lines which indicate where a photograph, llustration, or page should be eliminated or trimmed. In color printing, registration is the method of correlating over¬lapping colors on one single image. When printing an image that has more than one color, it is necessary to print each color separately, and to ensure that each color overlaps the others precisely.
Colour bar- To ensure that correct colours
are printed, a colour bar is printed outside the area of the material that will form the final product.
Registration marks- They look like sight
targets. They are printed outside the area that forms the final product.
DPI – Dots (or pixels) per Inch; Resolution
that varies across media. For print, image files are optimized at 300 DPI. For the Web (GIF and JPEG file formats), files are optimized at 72 DPI, the number of pixels across one inch of most monitors.
Printer Marks 33
In prepress, Imposition means arrangement of pages on the press sheet so that when folded the pages read consecutively. How one arranges the pages on the sheet depends on the size of the press sheet and the pages and how the job will be folded and bound. It is done so as to obtain faster printing, simplify binding and reduce paper waste. Correct imposition minimizes printing time by maximizing the number of pages per impression, reducing cost of press time and materials. To achieve this, the printed sheet must be filled as fully as possible.
B B
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The arrangement of pages on the printer’s sheet is affected by five different parameters: • Format of the product: The size of the finished page determines how many pages can be printedon a single sheet. • Number of pages of the printed product: Thecompositor must determine how many sheets are to be printed to create a finished book. • Stitching/binding method: The compositor must understand how the sheets are placed to form the signatures that compose the finished book. • Paper fiber direction: Many papers have a “grain,”reflecting the alignment of the paper fibers. These fibers must run lengthwise along the fold, which influences the alignment, hence the position, of the pages on the printed sheet. • Finishing and binding: To understand how the pages are related to each other. This is made by folding several sheets of paper in the way the press will print and fold the product. A little copy is then created, and this can help paginate the product. An 8 page pamphlet is actually printed with pages coupled 8+1, 2+7, 6+3, and 4+5 rather than in 1-2-34-5-6-7-8 order. When the pamphlet is back to back and folded, the pages will be in the correct order.This process is referred to as pagination or imposition.
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Paging & Imposition 34
8 page Signature folding
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1
2
7
6
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8 page back-to-back and folded
Types of Imposition
B B
A B B
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Ganged imposition: When one job on each press sheet would be a very inefficient use of the equipment, more than one job is run on the same sheet. Eg: It would be impossible to print 2x31/2 in business cards on 11x17 in press. To overcome this, several jobs are ganged toÂŹgether, reproduced on a large sheet and then cut to final sizes.
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A A AAB A A B Signature Imposition:
A A A B 8
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A large single sheet is frequently passed through a printing press and then folded and trimmed to form a portion of a book or magazine. This process is called signature imposition. Four-, eight-, twelve-, sixteen-, twenty-four-, and even forty-eight-page signatures are common press runs. The printer must impose the pages in the proper positions so they will be in the correct 7 sequence when folded in the final publication. 8 1 2 7
B AWork-and-turn imposition employs one printing plate 5 Bboth to print 6 on 3 sides of 4 a single 5 piece of Work and Turn Imposition:
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paper. The sheet is first printed on one side, the pile is turned over, and the sheet is fed through the press again with the same gripper edge (first edge that enters the press).
A A A B
Work and Tumble Imposition: On the second pass through the press, the pile is tumbled or flipped so that the opposite edge enters the press first. This is generally not used where fit(critical image position) is desired such as multi colour jobs.
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Ink Ingredients Pigment: Ingredients responsible for the color. Vehicle: Liquid portion of the ink. Purpose is to carry the pigment to the substrate.
Ink characteristics Consistency of the ink: On prolonged exposure to air and the increase in heat produced by the roller,the consistency may vary from time to time. Tack:Stickiness of the ink. Resistance of the ink film to split. Splitting occurs when the ink from printing plate is transferred to the printing blanket. Improper transfer leads to bad quality of print Viscosity: Degree that ink resists the flow when under force. Viscosity also can change with the frictional and heat generated by the roller train. Inkometer is used to measure the viscosity. Length: Ability of the ink to flow. Necessary for the ink to move properly through the roller train of the press to achieve best results. Opacity:Covering power of the ink. Different pigments have different degrees of opacity because of the substances used to produce the pigments. Tinting strength: Ability of the ink to produce a tint with addition of white pigment Permanency: The degree in which printed ink resists the fading power of light. The rate that an ink fade is known as degree of light fastness and is especially important when printed items, such a s an outdoor billboard, will be exposed to a high level of light.
Drying of Ink Absorption: Ink dried by absorption when printing application complete on absorbing surface such a s newspaper printer corrugated board. Oxidation: Comes in contact with oxygen of atmosphere and converting the ink on film on substrate to a solid Heat: The heat sets ink dry by evaporation in hot air dryers
Ink related problems Setoff: The transfer of ink from sheet to back of the next sheet. Caused by too much ink being applied or slow drying Ink adhesion: Result of set-off and slow drying ink, which in turn usually the result of poorly adjusted press settings. Mottling: Uneven appearance in the solid area of the printed document caused by uneven distribution of ink, non absorbent papers or faulty press adjustments.
Ink 36
Types of Paper
Coated paper Has glossy or matte finish.Generally very smooth and can be shiny More resistant to dirt, moisture and wear. Coating restricts the amount of ink that is absorbed by the paper and how the ink bleeds into the paper Paper and clay or other coating applied to one or both sides is coated paper. Uncoated paper Generally more absorbent of ink that a coated paper. Generally not as smooth as coated paper and tends to be more porous. Used for letterhead, envelopes and printed material that is aiming for a more prestigious or elegant look.
Matte
These paper have a thin coating applied which is not buffed to a shine. It has a dull finish.
Cartridge paper
Thick white with stiff feel more rag contact preserved for long time used in sketchbook certificates and stamp paper.
Mirror coat
Cast coated with China clay, mirror finish
Cards
Thicker paper ~200 gsm.
Photo paper
For reproduction of photographs. Photo paper is usually divided into glossy, semi matte or silk, and matte finishes.
Greyboard
Lined or unlined board made from waste paper. It has rough texture good bulk and is grey in color. Used for packaging materials or cover for publications.
Recycled paper
Made from waste paper mixed with fresh wood pulp. If the paper contains ink, then it must be de-inked. Kraft paper, plastic coated paper and papers that are waxed are usually not recycled because the cost is high.
Paper is a natural product because it is manufactured from a natural and renewable raw material, wood. It also has another big environmental advantage: it is 100% recyclable.
Paper 37
Grammage The weight of paper in countries that use ISO paper sizes is defined by ISO 536 Paper and BoardDetermination of Grammage. This standard defines Grammage as grams per square metre. Thus the weight of a single sheet of A0 paper defines the grammage of that paper type as A0 size is defined by ISO 216 as having an area of 1 square metre. An A0 sheet of 80gsm paper will weigh 80 grams, an A0 sheet of 100gsm paper will weigh 100 grams and so on.
Paper standards Basically two types, British standards and International standards. Some popular know paper sizes Foolscap - 13.5”x17” Demy- 17.5”x22.5” Medium- 18”x23” Royal- 20”x25” Crown- 15”x20” Imperial- 22”x30” When paper is divided into half the lloger side, it is called the Folio. Half of folio is know as 4to, half the above is 8vo and so on.
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Britian and Europe, metric ISO ‘A’ sizes are so common. The starting point size A0 is the area of a square meter. Folding A0 sheet in half along rh longer size results in A1, folding A1 results in A2 and so on. The height and width are in the ratio of one to the sqare root of two. This proprtion remains the same. This feature makes it very simple to adapt one design for several purposed (postcard, leaflet and a poster) A0 - 841 mm x 1189 mm A1 - 594 mm x 841 mm A2 - 420 mm x 594 mm A3 - 297 mm x 420 mm A4 - 210 mm x 297 mm A5 - 148 mm x 210 mm A6 - 105 mm x 148 mm B sizes Covers the intermediate for special applications such as oversize documents and posters. B0 - 1000 mm x 1414 mm B1 - 707 mm x 1000 mm B2 - 500 mm x 707 mm B3 - 353 mm x 500 mm B4 - 250 mm x 353 mm B5 - 176 mm x 250 mm B6 - 125 mm x 176 mm C size Folders, postcards, and envelopes. The mainuse of the size is for envelopes for A size sheets. Hence an A4 sheet will fit into a C4 envelope an A6 in C6 etc.
Paper Standards 39
Half Fold
Cutting Edge
Tri-Fold
Folding Edge
Folding is the process by which a press sheet is folded. There are almost an unlimited number of ways paper can be folded. Printing services has a variety of folding options.
This process involves the use of metal dies to give the paper or the substrate products specific shapes or design that cannot be accomplanished by a straight cut on a press or a guillotine cutter. Platten and cylinder mechanism(once used often inletterpress) is used for this. eg: labels, envelopes, folders, cartons etc.
Folding
Die-cutting
Map Fold
Post Press 40
Book binding is the process of physically assembling a book from a number of folded or unfolded sheets of paper or other material The types of binding can be broadly classified as:
Stationary Binding - Wire stitching - Office stationary - Loose leaf
Library Binding - Soft cover - Hard cover Library binding Has further 2 basic types depending on the spine: - Flat back bind - Round back bind
Paper Grain Paper, like wood, has a grain. If a book is printed with the paper grain parallel to the spine it will open more easily and lay flat. Adhesive binding on paper with the wrong grain direction can produce disastrous results.
Loose Leaf Binding Cut pages are punched with holes to accommodate the metal rings or posts contained in the binder.- Pages can be added or removed easily.- The ring binder also has the advantage of allowing the pages to lie _at when the book is open, making it a good choice for technical or training manuals.- Its of three types: • Flexible Binding • Spiral Binding • Ledger
Binding
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Spiral Binding binding consists of a continuous wire, which is coiled through evenly spaced holes that have been punched into the pages of a book. - The spiral wire can be made of metal, plastic, or plastic coated metal. - When the books are open, the pages lie _at. - The pages can also be folded over completely, which makes spiral binding a good choice for training manuals, cookbooks, notebooks, and calendars. - Another popularly used binding method is “wirobinding�, comes according to the diameter.
Flexible Binding/ Perfect Binding The single sheets are gathered, stacked, and placed in special equipment at an angle of 45 degree. - The binding edge is scrubbled on both the sides and then covered with glue, so that the papers bind together with the glue. - A cover is attached to the book and is held in place by the glued spine. - The title and other pertinent information are often preprinted on the area of the cover that attaches to the binding edge. - This is used to bind many types of publications including magazines, catalogs, paperback books, and telephone directories. - Perfect binding is most successful when the paper grain runs parallel with the spine of the book.
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During the module we had an opportunity to have a hands on experience of binding. We tried three types of bindings, • Pad Binding This type comes under stationary binding in which pages are stuck on one edge. This binding is done in a way so that you can easily tear-off the paper. •Perfect Binding It is one of the cheap methods to bind the books as it only involves sticking the pages on one edge similar to pad binding but securing it at the spine. This has limitations in terms of durability. •Section Sewed This is a very secure way of binding in which the signatures are cut and folded into sections of 4 pages each ( we made 6 sections of 6 pages each ) and are sewed together with needle and thread.We also made a hardcover jacket with a spine for the same in quarter binding style.
Binding 43
Planning is one of the most important parts of the process. Improper planning, design, and setup can cost more time and money, or can even create unprintable projects. You must know how you are going to finish the printed piece before you start it. Things to keep in mind while planning the project are: • Trim size- of the finished sheet allow the best use of the signature sheet a small change in only one dimension can save a lot of wasted paper. • Dummy print- make a dummy to make certain you have is of the correct amount of pages signature consist of 48 and 16 pages in most cases • Will the paper you have chosen run through the press? Some light weight and vert heavy stock may give you problems also some paper come in certain size only and will have to be cut down, causing paper easy. • how many ink units are on the press if you are printing a job with four colour process three spot colours and varnish, the job will require an eight unit press. • Which paper and printing process will be used? You need to know this information so that you can set the correct halftone screen, image resolution (1.5-2) times the halftone screen), and dot gain for photographs.
Planning & Design 44
Case study 1:- NID Poster Name of job - NID admission poster 2001-2002 (GDPD) Number of colors 2 colors on one side Finished size 11”x 22” Quantity 4000 copies (A) Paper: Ballarpur super printing paper 23”x36”x26.6 kg Unfinished size - 12”x23” = 3 posters from 1 sheet of 23”x36” = 4100 / 3 = 1355 sheets = ~(1400/500) reams = 2.8 reams Hence cost @50 rupees/ kg, = 1350/ream x 2.8 reams = Rs. 3800 ~ (B) Positive: 11” x 22”= 29 cms x 5cms = 1653 sq. cms Hence, 1653 x @Rs 0.12/sq.cms x 2 (since 2 colours) = Rs 379 (C) Platemaking: 2 colour = 2 plates @ 600 per/ plate = Rs 1200 (D) Printing: 2 plates x 4 thousand x @ 900 per plate (includes ink, overhead, labour) = Rs 1200 (the costing here is per plate otherwise the rates are fixed for 4000 copies) Total A+B+C+D+additional 10% = 13579 + 10% = 14936.9/4000 = Rs 3.73/ poster
Costing 45
Case study 2 - Bandhini Book Name of the job- Bandhini book No. of colours- 1 colours on two side Finished size- 5.5 x 10.5 Quantity- 1000 copies A) Paper: Ballarpur offset paper 23�x36�x26.6 kgs @Rs 50 per kg Cover: imported art card 210 gsm No. pf pages= 72+4 pages cover = 24 pages per sheet = 72 sheets /24= 3 sheets x 1000 copies = 3000 sheets + 10% wastage ( i.e. 300 sheets) = 3300/500 sheets per ream = 6.6 Reams x Rs. 1330 per ream = Rs. 8778 (A)
Costing 46
B) Cover-1100 copies/6 = 185 sheets x 2 packets @ Rs. 1387/packet =Rs. 2775 C) Layout & Plate making= 3 sheets of paper = 6 plates 6 plates x Rs 600/plate = 3600 For cover 2 plates x Rs. 250/plate (small size) = Rs. 500 = 4100 D) Processing: Image setting (positives) - 72 pages / 2 = 36 positives 36 positives x Rs. 330/Tabloid = Rs. 11,880 Cover 2 Colour positives x Rs. 330 = Rs. 660 = Rs. 12,540 E) Printing inside 6 plates x 1000 x Rs.900 = Rs. 5400 cover 2 plate x 1000 x Rs. 300 = 600 = Rs. 6000 F) Binding - cutting, gathering, folding, stitching & finishing 1000 copies x Rs. 5 per copy = Rs. 5000 A + B + C + D + E + F + 15% = Rs. 45, 072 45,072/ 1000 copies = Rs. 45.07 per copy
Alternative method : Calculation using CtP process, which save positive cost. CtP cost of 23� x 36� plate is Rs. 400.00/ plate x 6 plates = Rs. 2400.00 CtP for cover plate is Rs. 200.00/ plate x 2 plates - Rs. 400.00 2800.00 (CtP) A + B + C + CtP + E + F + 15% = Rs. 33,871 33,871 / 1000 copies = Rs. 33.87 per copy
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The field visit helped us gain a practical view-point on the various processes, right from pre-press, press to post-press. We studied the following machines and techniques throughout the visit Location - Art-o-print, Sarkhej Art-O-Print is a partnership firm established in April 1996. The company specializes in printing and packaging materials with facilities equipped to manufacture large and small volumes of various products - Packaging Material, Braille on Pharmaceutical Packaging, Pharma Outserts, Pharmaceutical Product Packaging, etc.
CtP machineWe studied the process of converting the artwork into the printing plate by computerised methods.
Offset Printing-
A 5 color offset machine setup. This was a 4 color CMYK + 1 unit for varnishing + 1 spot/metallic/texture printing unit.
Perfecting Press-
A Perfecting offset press with facility to print 1 colour on both the sides or 2 colours on one side.
Die cutting machine-
Cut outs for small cartons which can be manually folded to form packaging were being cut. This came in the post press stage where the prints are received already from the previous stages.
System of Storage-
An automated system was employed for paper storage where the paper was tacked in multistory arrangements. Whenever the desired paper is needed, the inputs are given at the controls in the bottom, after which the crane system fetches the paper for the purpose.
Field Visit 48
Flexography-
The Flexography machine was processing lables (stickers) printing job in 6 colors.
Bobst box manufacturing machine-
The high speed folding machine was also present which folded small sheets of paper which contained information regarding particular medicines. The Quality checker machine was an important machine in the industry which employed high end technologies since the company has to meet the requirements of international clients. Every copy of the product is compared to the master layout. The machine also has a Braille embosser (for the visually challenged).
Folding-
The paper creasing and folding by machines and manual process was demonstrated.
Corrugated Sheets and Boxes-
This particular industry is specialized in making corrugated cardboards for packaging. The demonstration of various machines from the preparing different types of sheets to the end part of the process where the sheets are cut, pasted and stapled into boxes . It was very helpful to understand how exactly the work done by the designer is taken ahead and how the industry works.
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