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Fig ure 4.3 Animated color map (linked to QR code): http://www-personal.umich.
edu/~copyrght/image/solstice/sum99/sat.gif . Shows change in the resulting saturation
as one moves along the y-axis. Derived from Netscape 7.2. Source: Arlinghaus, S. L.
and W. C. Arlinghaus. 1999. Animaps III: Color Straws, Color Voxels, and Color Ramps.
Solstice: An Electronic Journal of Geography and Mathematics. Volume X. No. 1. Ann
Arbor: Institute of Mathematical Geography. Source of base image: Netscape software.
http://www-personal.umich.edu/%7Ecopyrght/image/solstice/sum99/animaps3.html.
one can allow saturation to vary and can keep hue and luminosity fixed
(Figure 4.3). When luminosity is once again fixed at 120, and hue at 180,
a structurally identical situation occurs (to that above). To see a saturation-
straw, one would need to take all 256 colors available in the flashing rect-
angle and stack them up in order of progression. The inal case, in Figure
4.4 , keeps hue and saturation fixed and allows luminosity to vary. Thus,
one imagines a point in the base hue/luminosity plane fixed at (180, 120)
and variable height shown in the luminosity straw reflecting changes in the
single color-point as one alters luminosity. In this latter case, the obvious
straw that appears is in fact the actual luminosity straw sought. In two of the
cases, there is no evident straw of color and in the third there is; visualiza-
tion is not impossible but it is made difficult.
An alternate way to visualize all this is to think of a cube (in three-space) of
256 units on a side. Label the x -axis as hue, the y -axis as saturation, and the
z -axis as luminosity. Then, draw a plane parallel to the base plane (bottom
 
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