Allan Blase Joseph Rodrigues

Weighting function for the measurement of lightness differences in gonioapparent and dark colors

In gonioapparent colors, as Lightness increases, larger ΔL*s as measured by CIE76 are visually acceptable. This study used Logit Analysis of visual observations of lightness difference to determine this dependency of ΔL* on absolute L*. A linear functionality was found. Non-linearity of this function for very dark colors observed at flop angles, where sparkle is not observed lead to a further study of dark solid colors.