9.5.2

124 • CHAPTER 3
CONFIGURATION • 125
Figure 3 (left): The colors that can be displayed can be represented in a 3D coordinate system. Figure 4
(right): Less technical than RGB, and better suited to painters and artists, is the HSV system.
The color pigments for the screen dots have been selected in such a way that when equal parts are
added they result in a white that comes close to what the human eye perceives as a pure white. By
beaming different intensities at the three dots it is possible not only to generate the eight basic colors
(black, red, green, yellow, blue, magenta, cyan and white) that are the result of mixing the three
primary colors, but a huge range of mixed colors (Figure 3, above).
The number of colors possible is determined by the number of gradations in the intensity of the
electron beam. Using four gradations per primary color results in 4 x 4 x 4 = 64 colors. The standard
is 256 gradations per primary color, which gives 256 x 256 x 256 = 16,777,216 colors. These colors can
be represented in a three-dimensional coordinate system (Figure 3). The coordinate axes are formed
by the three primary colors. Black is at the origin. Mixed colors between red and green form the base
plane. Moving upward, more and more blue gets mixed in, until white is reached at the front corner
of the cube. All white shades lie on the line connecting the origin with this corner.
Less technical, and therefore better suited for painters and artists, is the HSV model (Figure 4). H is
the hue, S the saturation, V the color value.
The six basic colors (red, yellow, green, cyan, blue, magenta) form a hexagon around the color white,
together with the color black. The hue is the angle, starting with 0° for red, through 180° for cyan, to
270° for magenta. The saturation (S) is measured radially towards the outside. On the inside, along the
black/white axis, its value is 0.0, outside; at the hexagon’s edges, it is 1.0. The greater the saturation,
the more intense the hue. The value (V) is measured in the direction of the black/white axis. At the
height of white it has the value 1.0; downwards it decreases until reaching the value 0.0 for black.
The color value lets you darken the hue.