La Nature se dévoilant devant la Science

Notice that:
The color solid depends upon the spectrum of the
illuminant (not just the color).
For instance, if you prepare a “white” illuminant from
two complementary monochromatic beams, the color
solid collapses to a planar parallelogram.
Conclusion:
The envelope of all color solids for a given white color is
the intersection of the spectrum cone and its inverted
copy from the white point.
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