Graphics Programs Reference
In-Depth Information
Fig. 9-1-3
The
Color
Picker
, when set to enter
HSB values, now
represents Red tones
ranging from white to
black.
and darker. Click the
B
radio button and again, the palette
updates showing our red in the upper left corner with the
palette progressively getting lighter toward the bottom. This is a
good way to illustrate how color models are three-dimensional.
We have three individual two-dimensional plots shown in this
palette. Each radio button for each color model will show a
different slice of the color model within the palette so we can
pick a color, a degree of saturation, or a degree of luminance
(lightness).
6.
If you click back to the
R
radio button you'll see the palette
change to the opposite, where hues can be selected in the palette
and density (lightness to darkness, or what is better called
luminance
) is now selected by the vertical bar. This provides an
illustration of how these two color models share a method of
defining hue and luminance.
7.
Click back on one of the
HSB
radio buttons. Notice that the
255 Red value is a zero hue but 100% saturation and 100%
luminance. Click the
S
field and enter zero. Now all we see in
the palette are grays. Zero saturation means no color (hue) is
present, just shades of neutral gray. The brightness is still at
100% so we have moved from a pure red (
R255/G0/B0
) to
R255/G255/B255
, or as seen in the HSB area,
H0/S0/B100
. As
you continue to alter the values, you'll begin to understand the
relationship between RGB and HSB. The two models are simple
to understand. Since the CMYK values are based on the CMYK
profile set in Color Settings and are, of course, so device-
dependent that it becomes difficult to peg specific values.
