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Subtractive color model, Trapping – Xerox CX240 User Manual

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Spire CX250 Color Server User Guide

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%.

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.

Variable Information (VI)

Variable information (VI) jobs are jobs in which the printed materials
are individualized for specific recipients or purposes. These materials
can include bills, targeted advertising and direct mailings.

Vector drawing

The geometric system used to define lines and curves in many
computer graphics most often used for line drawings.

Vignette

See Degradé.

Virtual Printer

For Macintosh and PC networks, the Spire CXP Color Server
provides three default network printers, known as virtual printers.
Virtual printers contain preset workflows that are automatically
applied to all print jobs processed with that virtual printer.

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