AA:  Authors Alterations, changes other than corrections, made by a client after the proofing process has begun.  AA's are usually charged to a client as billable time.


Cut-back:  The process of reducing the size of an image so that the printed area produced by such a cut-back can be covered by an overprinting area.Cyan:  One of four standard process colors.   The color blue.

Alt:  Hue of a subtractive primary and a 4-color process ink.  It reflects or transmits blue and green light and absorbs red light.

Cylinder:  In flexography, for no particular reason, most rollers in the printing press are called rolls which the rubber plates are mounted, and the one which receives the impression, and these are usually referred to as cylinders, i.e., Plate Cylinders, Impression Cylinder.

Densitometer:  A quality control device to measure the density of printing ink.

Alt:  In photography, a photoelectric instrument which measures the density of photographic images, or of colors.  In printing, a reflection densitometer is used to measure and control the density of color inks on the substrate.


Density:  The degree of color or darkness of an image or photograph.


Digital plates:  Printing plates that can be exposed by lasers or other high energy sources driven by digital data in a platesetter.


Digital printing:  A system of printing, which involves linking state of the art printing presses and computers, bypassing the traditional route of making printing plates.

Alt:  Printing by plateless imaging systems that are imaged by digital data from prepress systems.


Dot gain or spread:  A term used to explain the difference in size between the dot on film versus on paper.

Alt:  A phenomenon, which occurs when wet ink comes in contact with paper.  As the halftone dots are applied to the paper, the wet ink spreads, causing the dots to increase in size and halftones to appear darker.  A number of factors affect dot gain.


Dot growth:  The enlargement of a halftone dot from the printing plate to the printed image as a result of pressure needed to transfer the ink onto the substrate.


Dots per inch (dpi): A measure of the resolution of a screen image or printed page.  Spots per inch (spi) is a more appropriate term.


Doughnut: The appearance of a screen dot that has printed the circumference of the cell while not printing a complete dot.

 Drift:  1) The continued deformation of rubber under strain.  2) The change in a given durometer reading after a specified period of time.


Duplicating film:  A film for making positives from positives, and negatives from negatives.  In color reproduction, a special film used for making duplicates of color transparencies.


Elastomer:  Any rubber-like substance or polymer.


Elastomeric:  Flexible and resilient.


Elliptical dot:  In halftone photography, elongated dots that give improved gradation of tones particularly in middle tones and vignettes - also called chain dots.


Flexography:  A method of direct rotary printing using resilient raised image printing plates, affixed to variable repeat plate cylinders, inked by a roll or doctor blade wiped engraved metal roll, carrying fluid or paste type inks to virtually any substrate.


FM (frequency modulation) screening:  A means of digital screening.  See stochastic screening.


 4-color-process:  The process of combining four basic colors to create a printed color picture or colors composed from the basic four colors.


Gear chart, or gear selector:  A handy reference compilation of the various printing lengths, or repeats, obtainable within the different gearing systems.


Gear marks:  A defect in flexographic printing.  Usually appears as uniformly spaced, lateral variations in tone exactly corresponding to the distance between gear teeth.


Gear streaks:  In printing, parallel streaks appearing across the printed sheet at same interval as gear teeth on the cylinder.


Gigabyte (GB):  One billion bytes.


 Graphic designer:  An individual who solves communication problems, using visual elements (pictures and type) to convey an idea or concept.


Gray balance:  The dot values or densities of cyan, magenta and yellow that produce a neutral gray.


Gray level:  The number of gray values that can be distinguished by a color separation filter - usually 256.


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.


 Hairline:  A very thin line or gap about the width of a hair or 1/100 inch.


Hairline register:  Register within " 2 row of dots.


Halation:  In photography, a blurred effect, resembling a halo, usually occurring in highlight areas or around bright objects.


Halftone:  Converting a continuous tone to dots for printing.

Alt:  A reproduction of a continuous-tone image (i.e. a photograph or painting), through a screening process, using fine dots of varying size and spacing to reproduce the shades and textures of the original.


Halo:  An undesirable peripheral outline of the printed image.


Hard dot:  See soft dot.


Illustrator:  An individual who draws or paints original artistic images for use in commercial art.


Image:  A design or drawing.


Image area:  Portion of paper on which ink can appear.


Imagesetter:  A high-resolution device that prints directly to plate ready film.


JPEG:  Joint Photographic Electronic Group:  A common standard for compressing image data.  JPEG is not commonly used in printing because of data loss.


Kilobyte (KB):  1,000 bytes.


 Laser:  The acronym for Light Amplification by Stimulated Emission of Radiation.  The laser is an intense light beam with very narrow band width that can produce images by electronic impulses from digital media.


Lines per inch:  The number of rows of dots per inch in a halftone.


Line screen:  A number used to express the fineness of a halftone screen, ranging from 25 to 300 or more lines per linear inch.  The number refers to the number of dots such a screen is capable of producing in a single row exactly one inch long.

Magenta:  Process red, one of the basic colors in process color.


Magnetic storage:  Any disc, film, tape, drum, or core that is used to store digital information.


Makeover:  In platemaking, a plate which is remade.


Matchprint:  Trade name for 3M integral color proof.

Alt:  A color proofing system developed by 3M.


Matrix:  A mold in which type is cast in linecasting machines.  In stereotyping, the paper mold or mat made from a type form.


Matte finish:  Dull paper or ink finish.


Megabyte (MB):  One million bytes.


Middle tones:  The tones in a photograph that are approximately half as dark as the shadow area.


Moire:  In color process printing, the undesirable screen pattern caused by incorrect screen angles of overprinting halftones.

Alt:  Occurs when screen angles are wrong causing odd patterns in photographs.


Mold:  A female form used for the production of desired shapes.  To form a matrix or rubber plate.  See Matrix.


Molding press:  A platen press in which matrices or rubber plates are formed.


Multicolor overprinting:  The technique of overprinting a given number of transparent colors to produce additional colors without using halftones.  Orange, green, purple, and brown may be thus produced by overprinting cyan, magenta and lemon yellow resulting in a total of seven colors from three.


Mylar:  A polyester film which exhibits exceptional mechanical strength and dimensional stability. Common substrate used in flexographic film printing.


Negative:  In photography, film containing an image in which the values of the original are reversed so that the dark areas appear light and vice versa.  (See positive)

Alt:  The image on film that makes the white areas of originals black and black areas white.


Neoprene:  A synthetic chlorinated butadiene rubber used in making flexo-rollers resistant to alcohols, cellosolve, water, aliphatic hydrocarbons and to a limited extent esters (acetates).  Not resistant to aromatic hydrocarbons.


Pixel depth:  The amount of data used to describe each colored dot on the computer screen, i.e. Monochrome is 1 bit deep, Greyscale is 8 bits deep, RGB is 24 bits deep.  Images to be printed as CMYK separation should be 32 bits deep.


Press proof:  In color reproduction, an approved copy or version of the final image to be printed, to be used as reference while printing.


Primary colors:  See additive primaries, subtractive primaries.


Prime coat:  Base coat applied first to enhance subsequent printing.


Process blue:  The blue or cyan color in process printing.


Process colors:  Cyan (blue), magenta (process red), yellow (process yellow), black (process black).


Process inks:  For high reproduction illustrations by halftone color separation process.  Colors are:  yellow, magenta, cyan, with or without black.


Process printing:  The printing from a series of two or more halftone plates to produce intermediate colors and shades.


Progressive proofs (progs):  Proofs made from the separate plates in color process work, showing the sequence of printing and the result after each additional color has been applied.


Proofing:  The stage of making a number of trial prints to judge the final result prior to editioning. 


Alt:  To position print in the proper position in relation to the edge of the sheet and to other printing on the same sheet.


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.

Alt:  Cross-hair lines or marks on film, plates, and paper that guide strippers, platemakers, pressmen, and bindery personnel in processing a print order from start to finish.


Registration:  The quality of alignment of the different colored inks as they are applied to paper.  (i.e. If the inks can be seen to overlap improperly or to leave white gaps on the page, the printing is said to be "out of registration" or "poor register".)


Repeat:  The printing length of a plate cylinder determined by one revolution of the plate cylinder gear.


Repeatability:  The ability to keep photo film and the images thereon in proper register.  Repeatability is usually measured in micrometers.


Resolution:  In electronic imaging, the quantification of printout quality using the number of spots per inch.


Respi screen:  A contact screen with 110-line screen ruling in the highlights and 220-line in the middle tones and shadows to produce a longer scale and smoother gradation of tones in the light areas of the copy.


RGB:  Red, Green, Blue - additive primary colors.


Rubber:  An elastomer material that is capable of recovering from large deformations quickly and forcibly.


Screen angles:  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 45E, magenta 75E, yellow 90E, cyan 105E.

Alt:  Frequently a desktop publisher's nightmare.  The angles at which halftone, duo tones, tri tones, and color separation printing films are placed to make them look right.


Screen-printing:  In flexography, refers to any tone printing work, whether half-tone or Ben Day.


Screened print:  In photography, a print with a halftone screen made from a halftone negative or by diffusion transfer.


Screen ruling:  The number of lines or dots per inch on a halftone screen.


Screen sizes:  Designated by the number of half tone dots in one linear inch of perpendicular or horizontal ruling.


Scribe lines:  The fine lines on the surface of the plate cylinder in an evenly spaced horizontal and vertical position to aid in mounting rubber plates accurately.  Center lines or other positioning guide lines applied to the non-printing areas of a rubber printing plate, to facilitate mounting on a cylinder.


Slug:  A rubber plate section, usually type, used as an insert.


Spectrophotometer:  The most sophisticated instrument for measuring brightness and color, able to test at varying wavelengths.


Spectrum:  The complete range of colors in the rainbow from short wavelengths (blue) to long wavelengths (red).


Spot color:  Single colors applied to printing when process color is not necessary (i.e. one, two and three color printing), or when process colors need to be augmented (i.e. a fluorescent pink headline or a metallic tint).


Stochastic screening:  A digital screen process that converts images into very small dots (14-40 microns) of equal size and variable spacing.  Second order


Substrate:  Any surface on which printing is done.


Subtractive primaries:  Yellow, magenta and cyan, the hues used for process color printing inks.


Terabyte(TB):  One trillion bytes.


Text:  The body matter of a page or book, as distinguished from the headings.


TIFF:  See Tagged Image File Format.


Tooth:  A characteristic of paper, slightly rough finish, which permits it to take ink readily.

Alt:  In screen printing, an action to roughen the surface of the screen prior to adhering a photo stencil.


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.

Alt:  The process of closing gas between different color inks as they appear on   the printed page.  Trapping color is achieved by use of chokes and spreads.


Undistorted artwork:  Artwork that has been prepared without compensation for the distortion that takes place after the printing plate has been mounted on the printing cylinder.


UV coating:  Liquid laminate bonded and cured with ultraviolet light.


UV ink:  Solventless ink that is cured by UV radiation.


Vignette halftone:  An illustration in which the background fades gradually away until it blends into the unprinted paper.

Alt:  A halftone whose background gradually fades to white.


Vinyl:  Informal generic term for any of the vinyl resins, or for film, or other products made from them.


Vinyl plastics:  Plastics based on resins made from vinyl monomers, except those specifically covered by other classifications such as acrylic and styrene plastics.  Typical vinyl plastics are polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, and polyvinyl butyryl, and copolymers of vinyl monomers and unsaturated compounds.


Viscosimeter:  Instrument used to measure the viscosity of ink, varnish, or other solution.


Viscosity:  Resistance to flow.


Vulcanization:  A curing process in which the physical properties of a rubber are changed.


Zahn cup:  A device for measuring viscosity.