Table of Contents
Advertisement
Working with Color
CIE color model
Hue, saturation,
and brightness
54
In the 1930s, the Commission Internationale de l'Eclairage (CIE) defined a
standard color space, a way of defining colors in mathematical terms, to
help in the communication of color information. This color space is based on
research on the nature of color perception.
By mixing any two spectral colors in different proportions, we can create all
the colors found between them. For example, it is possible to create the
same gray by mixing blue-green and red light or by mixing yellow-green and
blue-violet light. 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 perceived color.
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 select colors
by manipulating hue, saturation, and brightness. For example, Photoshop
uses a square Color Picker which can be reconfigured according to your
preference.
Advertisement
Table of Contents
