A flaw in equations for predicting chromatic differences

Abstract

Abstract Many formulas for predicting perceived color differences require that three terms be squared prior to the extraction of the square root of their sums. Two of these terms relate to chromatic differences measured along tritan and red‐green axes. The root‐mean‐square calculational procedure predicts that the relative directions of simultaneous chromaticity changes along these principal axes should not affect the perceived color difference. Experimental data are presented which strongly disconfirm this prediction.