A) colour images are metameric matches when their spectrally different colour stimuli have identical tristimulus values.

The requirements for such a metameric match can be calculated for a specified viewing condition (and for viewing conditions other than those specified, the chromaticity will not be judged to correspond). b) The corresponding colour chosen for the metameric match will not provide a spectrophotometric match. In practical applications, spectrophotometric matches are of only academic interest, and metameric matches are sought.

c) colour match, metameric, resulting from calculations based upon colorimetry, produces a visual match as evaluated by the CIE description of human observers.