Visual and Spectrophotometric Evaluations of Paired Glossy Color Prints Having Selected DE* Values.

A panel of 15 experienced colorists (8 male, 7 female) evaluated 34 paired glossy coated paper prints that included 8 different hues plus brown and gray. Paired samples for each hue (batch and standard) were selected that had nominal DE* values of 1, 2, and 4. Visual ratings of color difference, batch acceptance, lightness, chroma, and hue were compared with CIELAB measurements made with integrating sphere (D8) and directional geometry (0/45 and 45/0) spectrophotometers. Sphere colorimetric data were reported for both D8/CIELAB and D8/CMC2:1. In general, the agreement between visual ratings and colorimetric values was good, but very much related to hue. However, there were exceptions. In particular, large differences between visual ratings and instrumental values were observed when black was deliberately added to some hues. There were no significant differences when DE* values were measured and reported as D8/CIELAB, 0/45/CIELAB, and D8/CMC2:1. Because of the variance with hue, it was not possible to assign one DE* value that was visually acceptable for all hues. In general, the agreement between visual ratings and colorimetric values was good, but very much related to hue. However, there were exceptions. In particular, large differences between visual ratings and instrumental values were observed when black was deliberately added to some hues. There were no significant differences when DE* values were measured and reported as D8/CIELAB, 0/45/CIELAB, and D8/CMC2:1. Because of the variance with hue, it was not possible to assign one DE* value that was visually acceptable for all hues. Although there was good agreement between male and female rating for most color attributes, there were some differences. The significance of these differences requires additional study.