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

Figure 3.2: Hue, brightness and saturation. Different hues run horizontally;
the brightness of a single red hue is adjusted along the vertical
axis; saturation of the red hue is varied along the diagonal. Adapted
from [SB02].
light from a small aperture to a prism, where the light fanned out into a rainbow
of colors. Lights of shorter wavelengths (blue and violet) are refracted the most.
Newton then used a convex lens to collect the refracted components and pass them
through another prism. However, he would first selectively block out portions of
this modified spectrum, which would allow him to distinguish between pure and
composite light (light made up of several different components). To Newton, these
observations suggested that the white light from the sun was not pure, but made
up of several different colors. We now know that light from the sun contains a
multitude of energy from different regions of the electromagnetic spectrum, and is
the sum of many different wavelengths of light.
Color can be mixed in two drastically different ways, each method using its own
set of component primaries. Everyone knows from art class that various shades
of green are made when you mix blue and yellow paint together. This is called
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