Editing Spectral power distribution (section)

==Source SPD and color appearance==
[[File:Incand-3500-5500-color-temp-comparison.png|right|thumb|alt=Color temperature comparison of common electric lamps|Color temperature comparison of common electric lamps]]

The human visual response relies on [[trichromacy]] to process color appearance. While the human visual response integrates over all wavelengths, the relative spectral power distribution will provide [[color appearance model]]ing information as the concentration of wavelength band(s) will become the primary contributors to the perceived color.<ref name=mcol/>

This becomes useful in photometry and [[colorimetry]] as the perceived color changes with source illumination and spectral distribution and coincides with [[Metamerism (color)|metamerisms]] where an object's color appearance changes.<ref name=mcol/>

The spectral makeup of the source can also coincide with [[color temperature]] producing differences in color appearance due to the source's temperature.<ref name=meas/>