G
LOSSARY
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subtractive color model
A system in which color is produced by combining colorants such as paint, inks, or dyes
on media such as paper, acetate, or transparent film. All printing devices use the subtractive
color model.
subtractive primaries
Cyan, magenta, and yellow colorants used in subtractive color systems for color printing.
Combining the subtractive primaries produces darker colors. Black is added to the subtractive
primaries to compensate for deficiencies of the toners or inks, and for more efficient black
printing.
SWOP
The abbreviation for Specifications for Web Offset Publications. A standard of specifications
for separations, proofs, and color printing on a web offset press (
not
a sheet-fed press).
T
TIFF (Tag Image File Format)
A common format for exchanging raster graphics (bitmap) images between applications.
trapping
Printing technique in which some objects are printed slightly larger or smaller than you have
specified in an application in order to prevent white edges around these objects.
U
undercolor removal (UCR)
A method for improving wet ink trapping and reducing ink costs in process color printing.
In shadow areas where all three process colors (C, M, Y) overprint, the amounts of those
colors are reduced and replaced by black.
V
vector graphic
Graphic illustration created on computers where picture objects are defined mathematically as
lines or curves between points. These mathematical definitions are interpreted by an image
language such as PostScript. Vector images include artwork created with illustration
applications (such as Adobe Illustrator or Macromedia FreeHand) and page layout
applications (such as Adobe PageMaker).
W
white point
The color temperature of any white light source, typically expressed in degrees Kelvin
(for example, 6500 K, typical for the white of a monitor).
