Kenjiro Hashimoto

Preference for Japanese complexion color under illumination

To find the chromaticity coordinates of the “Preferred Complexion of Japanese Woman” under illumination, subjective estimation experiments were conducted on the complexions of 3 female models under each of 40 colors of illumination. The chromaticity coordinates of “Preferred Complexion” for each model were about the same together. The average chromaticity coordinates of 3 female models were (u′, v′) = (0.2425, 0.4895) under the standard illuminant D65. The “Preferred Complexion of Japanese Woman” in this experiment was compared with the “Preferred Complexion of Caucasian Woman” studied by Sanders. The “Preferred Complexion of Japanese Woman” was shifted to a slightly higher saturation and reddish in hue, compared with the actual complexion of “Japanese Woman.” On the other hand, the “Preferred Complexion of Caucasian Woman” was orange in hue, the same as the actual complexion of “Caucasian Woman.” The color shift of saturation of the “Caucasian Woman” was 3.5 times as large as that of the “Japanese Woman.”

On the field trials of CIECAM97s and its model structure

The structure of the color-appearance model CIECAM97s is examined. The problems with its chromatic-adaptation transform, called the Bradford transform, are discussed in detail. The contradictions existing between the measures at various stages of CIECAM97s are described, which are ea-eb, saturation s, chroma C, and colorfulness M. The main contradictions are (1) the inversion of chromatic components between test and reference colors at different measures; and (2) the similarity between chroma and colorfulness found in the experiments done under different adapting illuminances. The structural problems in CIECAM97s are clarified by comparing its predictions with those using CIECAT94LAB, which consists of the CIE chromatic-adaptation transform published in 1994 and the CIELAB formula.