Glossary of Terms
AA
Abbreviation for author's alterations.
Accordion fold
In binding, a term used for two or more parallel folds which open like an accordion.
Acrobat
Adobe software that embodies the PDF format.
Against the grain
Folding or feeding paper at right angles to the grain direction of the paper.
AM (Amplitude Modulation)
Halftone screening, as opposed to FM screening, has dots of variable size with equal spacing between dot centers.
Anti-offset or set-off spray
In printing, dry spray of finely powdered starch used on press to prevent wet ink from transferring from the top of one sheet to the bottom of the next sheet. This also separates the sheets on a micro level so oxygen can react with the ink to enhance ink drying.
Antique finish
A term describing the surface, usually on book and cover papers, that have a natural rough finish.
APR (Automatic Picture Replacement)
The replacement of a low resolution image by a high resolution image.
Aqueous Coating
A water-based coating that is applied like varnish to protect the printed surface. Aqueous coating can be applied in-line or off-line.
Backing up
Printing the reverse side of a sheet already printed on one side.
Barrel fold
In binding, two or more simple folds in which the outer edges of the pages are folded in toward each other.
Basis weight
The weight in pounds of a ream (500 sheets) of paper cut to a given standard size for that grade; e.g., 500 sheets 25"x38" of 50 pound book paper weigh 50 pounds.
Binding
The use of thread, staples, wire, glue, or other agents to collect sections or signatures into books, brochures and pamphlets.
Black printer
In color reproduction, the black plate, made to increase contrast of dark tones and make them neutral.
Blanket
In offset printing, a rubber-surfaced fabric which is clamped around a cylinder, to which the image is transferred from the plate, and from which it is transferred to the paper.
Bleed
An extra amount of printed image which extends beyond the trim edge of the sheet or page.
Blind embossing
A design which is stamped without metallic leaf or ink, giving a bas-relief effect.
Blind image
In lithography, an image that has lost its ink receptivity and fails to print.
Book paper
A general term for coated and uncoated papers. The basic size is 25"x38".
Burn
In platemaking, a common term used for a plate exposure.
Calibrate (color calibrate)
To fix, check or correct the gradation of color on a color monitor.
Caliper
The thickness of paper, usually expressed in thousandths of an inch (mils). In board, however, it is expressed as "points".
CEPS (Color Electronic Prepress System)
In digital prepress, a high-end computer-based system that is used to color correct scanner images and assemble images elements into final pages. They are device-dependent systems.
Chalking
In printing, a term which refers to improper drying of ink. Pigment dusts off because the vehicle has been absorbed too rapidly into the paper.
Chokes and spreads
Overlap of overprinting images to avoid color or white fringes or borders around image detail. Called trapping in digital imaging systems.
CMYK (Cyan, Magenta, Yellow, Black)
The subtractive process colors used in color printing. Black (K) is added to enhance color and contrast.
Coated paper
Paper having a surface coating which produces a smooth finish. Surfaces vary from eggshell to glossy.
Coating
An emulsion, varnish or lacquer applied over a printed surface to protect it.
Collate
In binding, the gathering of sheets and signatures.
Color balance
The correct combination of cyan, magenta and yellow to (1) reproduce a photograph without a color cast, (2) produce a neutral gray, or (3) reproduce the colors in the original scene or object.
Color correction
Any method such as masking, dot-etching, re-etching and scanning, used to improve color.
Color management
Program that takes scanners, monitors, printers, proofs and the color characteristics of the print into consideration.
Color separation
In photography, the process of separating color originals into the primary printing color components in negative or positive form using RGB filters.
Color workflow
The production workflow in a color managed environment.
Continuous tone
An image which contains gradient tones from black to white.
Contract proof
A color proof representing an agreement between the printer and the customer regarding how the printed product will look.
Contrast
The tonal gradation between the highlights, middle tones and shadows in an original or reproduction.
Cover paper
A term applied to a variety of papers used for the covers of catalogs, brochures, booklets and similar pieces.
Creep
Sometimes called "push out," it is the distance margins shift when paper is folded and/or inserted during finishing. The amount of creep will vary depending on both the number and thickness of the sheets and must be compensated for during layout and imposition.
Cromalin
A DuPont color prepress proofing system which is widely used to create proofs of four-color images. Using process colored powder instead of ink, separated film is exposed to approximate an image before printing.
Crop
To eliminate portions of the copy, usually on a photograph or plate, indicated on the original by cropmarks.
Crossover
An image that straddles two pages or runs across a spread. Critical for bindery work, particularly when the crossover image is created from two separate pages. Not all bindery methods area good candidates when crossovers need to match up exactly.
CTP (Computer-to-Plate)
In platemaking, Computer-to-Plate systems or platesetters eliminate the need for having a separate film-to-plate exposure system.
Cutoff
In web printing, the cut or print length.
Cutscore
In diecutting, a sharp-edged knife, several thousandths of an inch lower than the cutting rules in a die, made to cut part way into the paper or board for folding purposes.
Cyan
Hue of a subtractive primary and a 4-color process ink. It reflects or transmits blue and green light and absorbs red light.
Dampening system
In lithography, the mechanism on a press for transferring dampening solution to the plate during printing.
DCS (Desktop Color Separation)
In digital prepress, a data file defined to assist in making color separations with desktop systems. Using DCS five files are created - four color files, containing the cyan, magenta, yellow and black image data, and a composite color preview of the color image.
Debossing
To press an image into paper so it lies below the surface.
Densitometer
In photography, a photoelectric instrument which measures the density of photographic images, or of colors. In printing, a reflection desitometer is used to measure and control the density of color inks on the substrate.
Desktop publishing
Process of composing pages using a standard computer, off-the-shelf software, a device independent page description language like PostScript and outputting them on a printer or imagesetter.
Diecutting
The process of using sharp steel rules to cut special shapes for labels, boxes and containers, from printed sheets. Diecutting can be done on either flatbed or rotary presses. Rotary diecutting is usually done inline with the printing.
Digital Asset Management (DAM)
Also know as Media Asset Management, it is a segment of the content management market focused on the systematic cataloging and management of digital media (text, images, video and audio) and some physical media to enable their efficient storage, retrieval and reuse.
Digital color proof
A color proof produced from digital data without the need for separation films.
Digital inks
See toners.
Dots Per Inch (dpi)
Number of dots in a line screen per inch. A measure of the resolution of a screen image or printed page.
Digital plates
Printing by plates that can be exposed by lasers or other high energy sources driven by digital data in a platesetter.
Digital printing
Printing by plateless imaging systems that are imaged by digital data from prepress systems.
Dithering
In computer graphics, a technique for alternating the values of adjacent dots or pixels to create the effect of intermediate values. Dithering refers to the technique of making different colors for adjacent dots or pixels to give the illusion of a third color.
Dot
Smallest screening element. The fineness of a halftone screen is measured in ‘lines per inch' or lpi. In AM screening the dots vary in size. In FM screening the dots are all the same size.
Dot gain
In printing, a defect in which dots print larger than they should, causing darker tones or stronger colors.
Download
Sending information to another computer or to an output.
Draw-down
In inkmaking, a term used to describe ink chemist's method of roughly determining color shade. A small glob of ink is placed on paper and drawn down with the edge of a putty knife spatula to get a thin film of ink.
Dummy
A preliminary layout showing the position of illustrations and text as they are to appear in the final reproduction. A set of blank pages made up in advance to show the size, shape, form and general style of a piece of printing.
Duotone
In photomechanics, a term for a two-color halftone reproduction from a one-color photograph.
Dynamic range
Density difference between highlights and shadows of scanned subjects.
Electrostatic plates
Plates for high-speed laser printing using zinc oxide or organic photoconductors.
Elliptical Dot
In halftone photography, elongated dots which give improved gradation of tones particularly in middle tones and vignettes.
Embossed finish
Paper with a raised or depressed surface resembling wood, cloth, leather or other pattern.
Embossing
Impressing an image in relief to achieve a raised surface; either overprinting or on blank paper (called blind embossing).
Enamel
A term applied to a coated paper or to a coating material on a paper.
Engraving
Printing method using a plate with an image (also called a die) cut into its surface.
Feeder
In printing presses, the section that separates the sheets and feeds them in position for printing.
Felt side
The smoother side of the paper for printing. The top side of the sheet in the paper manufacturing.
Finish Surface
Texture of a paperstock.
Flatbed scanner
A device that scans images in a manner similar to a photocopy machine; the original art is positioned face down on a glass plate.
Flexography
A direct printing technique. The printing areas are elevated compared to the non-printing ones. Primarily used in the packaging industry. The printing form is made of rubber or plastic material.
Flush cover
A cover that has been trimmed to the same size as the inside text pages.
Flying paster or splicer
In web printing, an automatic pasting device that splices a new roll of paper onto an expiring roll, without stopping the press.
FM (Frequency Modulation) Screening
A means of digital screening. See stochastic screening.
Foil Stamping
Printing method that releases foil from its backing when stamped with a heated plate or die.
Folding dummies
A mock-up of the job using the actual paper trimmed and folded to exact specifications.
Folding
To bend or crease a sheet of paper to create a printed or bound document.
Folio
The page number.
Font
In composition, a complete assortment of letters, numbers, punctuations, etc., of a given size and design.
Form rollers
The rollers, either inking or dampening, which directly contact the plate on a printing press.
Fountain solution
In lithography, a solution of water, a natural or synthetic gum and other chemicals used to dampen the plate and keep non-printing areas from accepting ink.
FPO (For Position Only)
In digital imaging, typically a low-resolution image positioned in a document to be replaced later with a higher resolution version of the same image.
Grain
In papermaking, the direction in which most fibers lie which corresponds with the direction in which the paper is made on a paper machine.
Gravure
Method of printing using metal cylinders etched with millions of tiny wells that hold ink.
Gray Balance
The dot values or densities of cyan, magenta and yellow that produce a neutral gray.
Gray scale
A strip of standard gray tones, ranging from white to black, placed at the side of original copy during photography to measure tonal range and contrast (gamma) obtained.
Gripper edge
The leading edge of paper as it passes through a printing press. Also, the front edge of a lithographic or wraparound plate secured to the front clamp of a plate cylinder.
Gripper margin
Unprintable blank edge of paper on which grippers bear, usually 1/2" or less.
Grippers
In sheetfed printing presses, metal fingers that clamp on paper and control its flow as it passes through.
Gutter
The blank space or inner margin from printing area to binding.
Hairline register
Register within +/- 1/2 row of dots.
Halftone
The reproduction of continuous-tone images, through a screening process, which converts the image into dots of various sizes and equal spacing between centers (AM screening), or dots of equal size with variable spacing between them (FM screening).
Halftone dots
The smallest unit that a screen consists of. All tones in print, both photographs and illustrations, are based on halftone dots.
Hexachrome
A version of hi-fi printing involving six color separations.
Hickeys
In offset lithography, spots or imperfections in the printing due to dirt on the press, dried ink skin, paper particles, etc.
Hi-fi Color
Subtractive color model that lets you add two to four colors in addition to CMYK in order to obtain a wider color range in print.
Highlight
The lightest or whitest parts in a photograph represented in a halftone reproduction by the smallest dots or the absence of dots.
Hi-res (high resolution)
An image that has sufficient sharpness (measured by the number of pixels per inch) to make it suitable for print reproduction.
Histogram
In digital prepress, a graph that displays the tonal range of a given image.
Hue
In color, the main attribute of a color which distinguishes it from other colors.
Imagesetters
In digital imaging, a generic term that applies to film-output devices for type and graphics. The difference between an imagesetter and a typesetter is in the format of the data that has been converted from discrete-character raster lines to raster data using bitmaps.
Imposition
In image assembly, the positioning of pages on a signature so that after printing, folding and cutting, all pages will appear in the proper sequence.
Impression cylinder
In printing, the cylinder on a printing press against which the paper picks up the impression from the inked plate in direct printing, or the blanket in offset printing.
Ink coverage
The amount of ink added in the printing process. Also describes the maximum allowed amount of each component color on a certain paper in a printing process. Expressed as a percent.
Ink drawdown
A special ink formulation prepared on the paper upon which the job will be printed.
Ink fountain
In printing presses, the device which stores and supplies ink to the inking rollers.
Ink-jet printing
In digital printing, a plateless printing system that produces images directly on paper from digital data using streams of very fine drops of dyes which are controlled by digital signals to produce images on paper.
JDF (Job Definition Format)
A data exchange standard that will act as a universal electronic job ticket that contains control data from print buying thorough estimating, customer service, prepress, press, finishing and dispatch. JDF contains production information rather than content data.
Jog
To align sheets of paper into a compact pile.
Knockouts
Type or images that reverse out of a solid or tint, allowing the paper to show through. Also called reverse.
Lamination
A plastic film bonded by heat and pressure to a printed sheet for protection or appearance. Lines Per Inch (lpi) The number of lines of output per inch; for example, a halftone of 85 lines per inch is lower resolution than a halftone of 120 lines per inch; lines per inch, lpi, line screen and screen frequency are all synonymous.
Lithographic Offset Printing (litho)
Printing method using plates whose image areas attract ink and whose non-image areas repel ink. Non-image areas may be coated with water or a coating, such as silicon, to repel ink.
Loop stitching
A variation on saddle stitching. The stitch, or wire, is formed into a circular loop which sticks out beyond the spine in the finished book. The loops are designed to slip onto the rings of a three-ring binder.
Loupe
A magnifying lens held close to the eye to examine printing. The most common is an eight-power, which enlarges an image by a factor of eight.
Magenta
Hue of a subtractive primary and a four-color process ink. It reflects or transmits blue and red light and absorbs green light.
Makeready
In printing, all work done to set up a press for printing.
Match color
A custom-mixed ink color that exactly matches a specified color. Typically chosen from numbered color matching systems. Also called spot color.
Matte finish
Dull paper finish without gloss or luster.
Metallic Inks
Inks containing metal powder that have a shiny reflective appearance.
Middletones
The tonal range between highlights and shadows of a photograph or reproduction.
Misregistration
A print phenomenon in which the component colors don't print directly on top of each other (i.e. in register).
Moiré
In color process printing, the undesirable screen pattern caused by incorrect screen angles of overprinting halftones.
Mottle
The spotty or uneven appearance of printing, mostly in solid areas.
Oblong
A booklet or catalog bound on the shorter dimension.
Offset
In printing, the process of using an intermediate blanket cylinder to transfer an image from the image carrier to the substrate. Short for offset lithography.
Opacity
That property of paper which minimizes the show-through of printing from the back side or the next sheet.
Opaque ink
An ink that conceals all color beneath it.
Overhang cover
A cover larger in size than the pages it encloses.
Overprinting
Double printing; Printing over an area that already has been printed.
Overrun
In printing, copies printed in excess of the specified quantity.
Packing
In printing presses, material, usually special paper, used to underlay the image or impression cylinder in letterpress, or the plate or blanket in lithography, to get proper squeeze or pressure for printing.
PDF (Portable Document File)
PDF is a universal electronic file format, modeled after the PostScript language and is device-and resolution-independent. Documents in the PDF format can be viewed, navigated and printed from any computer regardless of the fonts or software programs used to create the original.
Perfect Binding
A method of binding which uses adhesive to hold signatures or pages together.
Perfecting press
A printing press that prints both sides of the paper in one pass through the press.
Pica
Printer's unit of measurement used principally in typesetting. One pica equals approximately 1/6 of an inch.
Picking
In printing, the lifting of the paper surface during printing. It occurs when pulling force (tack) of ink is greater than surface strength of paper.
Pigment
In printing inks, the fine solid particles used to give inks color, transparency or opacity.
Piling
In printing, the building up or caking of ink on rollers, plate or blanket; will not transfer readily. Also, the accumulation of paper dust or coating on the blanket of offset press.
Pixel
Short for "picture element." A pixel is the smallest resolvable point of a raster image. It is the basic unit of digital imaging. Pixels per inch (ppi) States the resolution of images, monitors and scanners.
Plate cylinder
The cylinder of a press on which the plate is mounted.
Platesetter
An image recorder which images directly on plate material. Platesetters currently available use lasers to expose or image paper, polyester or aluminum plates.
PMS (Pantone Matching System)
Color charts that have over 700 preprinted color patches of blended inks, used to identify, display or define special colors.
Point
Printer's unit of measurement, used principally for designating type sizes. There are 12 points to a pica; approximately 72 points to an inch.
Poor trapping
In printing, the condition in wet printing in letterpress and lithography when less ink transfers to previously printed ink than to unprinted paper. Also called undertrapping.
Position proof
Color proof for checking position, layout and/or color breakout of image elements.
Preflighting
In digital prepress, the test used to evaluate or analyze every component needed to produce a printing job. Preflight confirms the type of disk being submitted, the color gamut, color breaks, and any art required (illustrations, transparencies, reflective photos, etc.) plus layout files, screen fonts, printer fonts, EPS or TIFF files, laser proofs, page sizes, print driver, cropmarks, etc.
Press proofs
In color reproduction, a proof of a color subject made on a printing press, in advance of the production run.
Process colors
In printing, the subtractive primaries - yellow, magenta and cyan, plus black in four-color process printing.
Quadtone
A term for a four-color halftone reproduction from a one-color photograph.
Raster image processor (RIP)
In digital imaging, a combination of computer software and hardware that controls the printing process by calculating the bitmaps of images and instructing a printing device to create the images. Most PostScript systems use a hardware RIP built into the printer.
Ream
Five hundred sheets of paper.
Register
In printing, fitting of two or more printing images in exact alignment with each other.
Register marks
Crosses or other targets applied to original copy prior to photography. Used for positioning films in register, or for register of two or more colors in process printing.
Resolution
In electronic imaging, the quantification of printout quality using the number of dots per inch.
Reverse
Images reproduced by printing ink around their outline, thus allowing the underlying color of paper to show through and form the image. Also called knockout.
RGB (red, green and blue)
The primary additive colors used in display devices and scanners. Commonly used to refer to the color space, mixing system or monitor in color computer graphics.
Right-angle fold
In binding, a term used for two or more folds that are at 90 degree angles to each other.
Saddle stitch
In binding, to fasten a booklet by wiring it through the middle fold of the sheets. Also called saddle wire.
Scaling
Determining the proper size of an image to be reduced or enlarged to fit an area.
Scanner
An electronic device used in the making of color and tone-corrected separations of images.
Scatter Proofs or Loose Color Proofs
Prepress proof of a halftone, duotone or color separation that is not assembled with other elements from a page. Also called random proofs.
Score
To impress or indent a mark in the paper to make folding easier.
Screen
A method of printing that breaks up continuous-tone images into printable dots.
Screen
In color reproduction, angles at which the halftone screens are placed in relation to one another, to avoid undesirable moiré patterns. A set of angles often used is - black 45 degrees, magenta 75 degrees, yellow 90 degrees, cyan 105 degrees.
Screen printing
A printing method used for large formats, such as billboards and hard print carriers, such as steel signs. The printing form consists of a finely woven cloth that lets through printing ink and is tightened to a frame. The non-printing surfaces are covered so that the ink cannot get through the cloth.
Screen ruling
The number of lines or dots per inch on a halftone screen.
Screen tints
Color generated by dots instead of solid ink coverage.
Scum
In offset lithography, a film of ink printing in the non-image areas of a plate where it should not print.
Self cover
A cover of the same paper as inside text pages.
Set-off
In presswork, when the ink of a printed sheet rubs off or marks the next sheet as it is being delivered. Also called offset.
Shadow
The darkest parts in a photograph, represented in a halftone by the largest dots.
Sharpen
To decrease in color strength, as when halftone dots become smaller; opposite of dot spread or dot gain.
Sheetfed
Printing from stacks of sheets that feed one at a time through the press.
Sheetwise
To print one side of a sheet of paper with one plate then turn the sheet over and print the other side with another plate using same gripper and opposite side guide.
Shingling
In image assembly and layouts, the center or gutter margin is varied according to the position of the page in the signature and the bulk of the paper.
Show-through
In printing, the undesirable condition in which the printing on the reverse side of a sheet can be seen through the sheet under normal lighting conditions.
Side guide
On sheetfed presses, a guide on the feed board to position the sheet sideways as it feeds into the front guides before entering the impression cylinder.
Sidestitching
A method of common binding where the folded signatures or pages are stitched along the side near the gutter margin. The pages will not lie flat.
Signature
In printing and binding, the name given to a printed sheet after it has been folded.
Silhouette halftone
A halftone of a subject with all of the background removed.
Skid
A platform support for a pile of cut sheets of paper.
Specular highlight
In photography or printing, a highlight that reflects a light source directly. When printed, specular highlights have no dots at all.
Spiral binding
A book bound with wires in spiral form inserted through holes punched along the binding side.
Spot color
Printing inks of special colors, for example from the color matching systems and swatch books. Generally used as a complement to black or to achieve an exact color four-color inks cannot provide. Mixed according to a recipe. Also called match color.
Spot varnish
Varnish applied to specific areas of a sheet, as compared to flood varnish.
Spreads
A technique of slightly enlarging the size of an image to accomplish a trap with another image. Also, a two-page arrangement of copy.
Star target
Film pinwheel used to measure resolution of plates during production and degradation during printing.
Stet
A proofreader's mark, written in the margin, signifying that copy marked for corrections should remain as it was.
Stochastic screening
A digital screening process that converts images into very small dots (14-40 microns) of equal size and variable spacing. Second order screened images have variable size dots and variable spacing. Also called Frequency Modulated (FM) screening.
Stock
Paper or other material to be printed.
Tack
In printing inks, the property of cohesion between particles; the separation force of ink needed for proper transfer and trapping on multicolor presses. A tacky ink has high separation forces and can cause surface picking or splitting of weak papers.
Tagged image file format (TIFF)
A file format for graphics suited for representing scanned images and other large bitmaps. TIFF is a neutral format designed for compatibility with all applications. TIFF was created specifically for storing grayscale images, and it is the standard format for scanned images such as photographs- no called TIFF/IT.
Thermography
Printing method using colorless resin powder that takes on the color of the underlying ink to create a raised printed surface.
Tints
Various even tone areas (strengths) of a solid color created by dots rather than solid ink coverage. Also called screen tints.
Toner
In digital printing, imaging material also called digital inks, used in plateless printing systems like electrophotography, magnetography, ion or electron deposition and laser printers. In inks, dye used to tone printing inks, especially black.
Transparent ink
A printing ink which does not conceal the color beneath. Process inks are transparent so that they will blend to form other colors.
Trapping
In printing, the ability to print a wet ink film over previously printed ink. Dry trapping is printing wet ink over dry ink. Wet trapping is printing wet ink over previously printed wet ink. In prepress, refers to how much overprinting colors overlap to eliminate white lines between colors in printing.
Trim marks
In printing, marks placed on the copy to indicate the edge of the page.
Tritone
A term for a three-color halftone reproduction from a one-color photograph, usually using two blacks and a gray.
UCA (UnderColor Addition)
In process color printing, used with GCR, UCA is ink added in shadow areas to increase color saturation.
UCR (UnderColor Removal)
In process multicolor printing, color separation films are reduced in color in neutral areas where all three colors overprint and the black film is increased an equivalent amount in the areas. This improves trapping and can reduce makeready and ink costs.
Uncoated stock
Paper that has not been coated. There are varying degrees of quality with the highest being Writing, Text and Cover papers.
Unsharp masking
Technique of adjusting dot size to make a halftone or separation appear in better focus. Also called edge enhancement and peaking.
-up
In printing, two-up, three-up, etc., refers to imposition of material to be printed on a larger size sheet to take advantage of full press capacity.
UV inks
In printing, solventless inks that are cured by UV radiation. They are used extensively in screen printing, narrow web letterpress and flexographic printing.
Vellum finish
In papermaking, a toothy finish which is relatively absorbent for fast ink penetration.
Vignette
An illustration in which the background fades gradually away until it blends into the unprinted paper.
Viscosity
In printing inks, a broad term encompassing the properties of tack and flow.
Warm color
In printing, a color with a yellowish or reddish cast
Washup
The process of cleaning the rollers, form or plate, and sometimes the ink fountain of a printing press.
Waterless printing
In offset, printing on a press using special waterless plates and no dampening system.
Web
A roll of paper used in web or rotary printing.
Web press
A press which prints on a roll of paper.
Wire-o binding
A continuous double series of wire loops run through punched slots along the binding side of a booklet.
Wire side
In papermaking, the side of a sheet next to the wire in manufacturing; opposite from felt or top side.
With the grain
Folding or feeding paper into a press with the grain of the paper parallel to the blade of the folder or the axis of the impression cylinder.
Work-and-tumble
To print one side of a sheet of paper, then turn it over from gripper to back using the same side guide and plate to print the second side.
Work-and-turn
To print one side of a sheet of paper, then turn it over from left to right and print the second side using the same gripper and plate but opposite side guide.