pigmented colorants: dependence on media and time - Cornell ...

Figure 3.5: Subtractive color mixing of cyan, yellow and magenta primaries
from pure white light. Adapted from [GM97].
reflected as in subtractive color). To create a given color, different combinations of
the red, green and blue color primaries are added together. Given several colored
lights described by RGB intensities Ci =(Ri,Gi,Bi), illuminating the same white
surface, the resulting color will be
C =
i
The light intensities are simply added together. For instance, red light (1,0,0)
and green light (0,1,0) form yellow light (1,1,0), as seen in Figure 3.6. Full intensity
of all three primaries forms white light (1,1,1), while the complete absence of light
is black (0,0,0).
Additive color can be executed by superimposing each illuminant (the equiv-
alent of perfectly aligning the images from three differently colored projectors).
However, current display technology borrows concepts from nineteenth-century
impressionist painters, such as Georges Seurat and Paul Signac. The two were
profoundly influenced by the French chemist Michel Chevreul and his ideas of si-
multaneous contrast and optical color mixing. The artists developed the style of
pointillism, where only pure hues of the artist’s palette are used, but the brush
marks are applied in dots that were close enough together to be blended by the
Ci
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