Hue, Saturation, And Brightness; Additive And Subtractive Color Systems - Xerox DocuColor DocuColor 4 User Manual

This is possible because of a phenomenon peculiar to color vision called
metamerism. The eye does not distinguish individual wavelengths of light.
Therefore, different combinations of spectral light can produce the same per-
ceived color.
6.1.3

Hue, saturation, and brightness

A color can be described in terms of three varying characteristics:
Hue, or tint (the qualitative aspect of a color-red, green, or orange)
Saturation, or the purity of the color
Brightness, or relative position between white and black.
Many computer applications include dialog boxes in which you choose col-
ors by manipulating hue, saturation, and brightness. For example, Photoshop
uses a square Color Picker which can be reconfigured according to your pref-
erence.
6.1.4

Additive and subtractive color systems

Color devices used in desktop publishing and printing simulate the range of
visible colors using a set of primary colors that are combined to create other
colors. There are two methods of creating a range of colors from a set of
primary colors. Computer monitors and scanners use the additive color
model. Printing technologies, including the DocuColor 4 LP/CP and offset
presses, use the subtractive color model.
Additive (RGB) color
Color devices that use the additive color model make a range of colors by
combining varying amounts of red, green, and blue light. These colors are
called the additive primaries. White is created by adding the maximum
amount of red, green, and blue light available. Black occurs wherever all
three colors are absent. Grays are created by adding varying amounts of all
three colors together. Combining varying amounts of any two of the additive
primaries creates a third, saturated hue.
A familiar device that uses this color model is the computer monitor. Moni-
tors have red, green, and blue phosphors that emit varying amounts of light
to display a given color. Scanners create digital representations of colors by
measuring their red, green, and blue components through colored filters.
6.1 The properties of color
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