CIE ΔE* (Color Difference) Equations
Pictured above is a combination handheld spectrophotometer and densitometer, the SpectroDens 4. The intent of using deltaE (ΔE) is to describe the distance between two colors. The Just Noticeable Difference (JND) of deltaE is usually 1. In other words, if two colors have a deltaE less than 1 it is imperceptible and larger than 1 is perceivable. Unfortunately, due to the nature of human color perception (our eyes), the visual perception of colors is different….