Spectral colors from 380nm to 780nm. Tick marks every 20nm.

Output is in sRGB.

spec.rel.png	Shows the color without correcting for brightness. Saturation
		and brightness are reduced to fit sRGB.
spec.abs1.png	Shows the equal energy spectrum. Saturation and brightness are
		reduced to fit sRGB.
spec.abs2.png	Also represents the equal energy spectrum. In the trade off
		saturation against brightness, brightness was given priority.