Xerox C8 - DocuPrint Color Inkjet Printer, User Manual, Page: 448 / 458

434 Spire CXP8000 Color Server User Guide
Stochastic screening A method of creating frequency-modulated halftones that depends
on the number of laser dots in a given area rather than the size of the
laser dots in a given area. The dots are randomly placed and very
small. Areas with a higher dot percent have more spots exposed in
that area and those with a low dot percent have fewer spots. Stochastic
screening is used to eliminate moiré and improve picture detail and
sharpness in high-end color printing.
Subtractive color model
A color process in which the red, green and blue components of the
original subject are reproduced as three super-imposed images in the
complementary (subtractive) colors of cyan, magenta and yellow
respectively. See also
CMYK , Process colors , Additive color model .
Three quartertone
Tone area of an image influencing the shadow detail and with density
values between the Midtone and the Dark Point. Typically printed
with a dot area near 75%.
Three quartertone Tone area of an image influencing the shadow detail and with density
values between the Midtone and the Dark Point. Typically printed
with a dot area near 75%.
Tone compression
The reduction of the density range of an original to the density range
achievable in the reproduction.
Tone reproduction curve
A graph showing the density of each point of the original and its
corresponding density on the reproduction.
Trapping
Creating and overlap (spread) or an underlap (choke) between colors
that adjoin each other to hide misregistration during printing.
Trapping is sometimes referred to as spreads and chokes, or fatties
and skinnies.
UCR
Abbreviation of Undercolor Removal. This is a method for reducing
the CMY content in neutral gray shadow areas of a reproduction and
replacing them with black. As a result, the reproduction appears
normal but less process color inks are used. See also
GCR .
Unsaturated color
A color whose highest value is less than approximately 80%. In an
unsaturated, dirty color, the difference in the values of the wanted
colors and the unwanted color is relatively low.
For example, when the color is red, 30% cyan, 80% magenta, 70%
yellow is more unsaturated than 0% cyan, 90% magenta, 80% yellow.