Color and luminance affect perceptual transparency of human skin

Abstract

Transparent skin has recently been one of the most important keyword in developing cosmetic products in Japan. Perceptual transparency must be related to colorimetric parameters, such as chromaticity and luminance. Therefore, we conducted psychophysical experiments to examine the effects of colorimetric parameters on the perceptual transparency. In Experiment 1, we examined whether luminance information has an effect on the perceptual transparency. A small patch of the cheek was clipped from a face image of a Japanese woman. Based on that image, we generated four kinds of stimulus corresponding to four levels of average luminance. Participant’s task was to choose the skin with higher perceived transparency using a 2AFC paradigm. The results showed that the skin with higher luminance values was perceived as more transparent. In Experiment 2, we examined whether chromatic information affects the perceptual transparency of skin. We asked participants to choose the color so that they can maximize their perceived transparency by adjusting the a*b*- chromaticities of the skin patch. The results showed that each participant has an ideal chromaticity so as to perceive transparency of skin though there are quite large individual differences among the participants. In addition, we found that redder skin looks more transparent.