Xerox Fiery color server User Manual page 117

G-7 Glossary
spectral light
The wavelengths of electromagnetic
radiation emitted by a given light source
that can be seen by the human eye.
spectrophotometer
An instrument commonly used in the
graphic arts industry to measure spectral
light according to a specified standard.
spot color
A color that is printed on its own
separation plate when separations are
specified. A spot color is printed using a
custom ink for that color, in contrast to
process colors that are printed using
combinations of cyan, magenta, yellow,
and black.
Spot Color Matching
See spot color.
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.
substrate
In printing, the material upon which the
job is printed.
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).
undercolor removal
In shadow areas where all three process
colors (C, M, Y) overprint, the amounts
of those colors are reduced and replaced
by black. This improves wet ink trapping
and reduces ink costs in process color
printing.
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
Illustrator or FreeHand) and page layout
applications (such as PageMaker).
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).