Analysis of colorimetric factors related to "feeling of depth" of painted automobile panels by using color simulator

This paper proposes a new method to analyze the factor of human feeling by using an experimental color simulator. It enables us to extract the colorimetric factors concerned with the feeling of depth (FOD) which arises psychophysically when we look into a painted automobile panel. The FOD is one of the human feelings and the same as the term "Fukami-kan" in Japanese. In our previous studies, it has become clear that the FOD arises from two psychological factors: color appearance and flake appearance on a panel surface. The former is a macroscopic factor and the latter microscopic. In this study, we try to analyze the relationship between FOD and color appearance. Graphic color panels generated by an experimental color simulator are used instead of real painted panels for our experiments, This color simulator generates a photorealistic graphic panel according to a calculation of the rendering algorithm based on an illumination model. Moreover, it has an ability to vary color appearance of the graphic panel by Munsell color parameters; hue, value and chroma, with photorealistic characteristic preservation. Using many graphic color panels, we analyze the effects of Munsell parameters on the FOD by a psychophysical method. As a result, several important facts related to the FOD have been extracted: the effect of hue on the FOD is cyclic; as value decreases and/or as chroma increases, the FOD becomes greater. Finally, applying the results to produce a new painted panel, it has been shown that it indicates a great more FOD than present.