Appearance Match between Soft Copy and Hard Copy under Mixed Chromatic Adaptation

Human visual system is partially adapted to the CRT monitor's white point and partially to the ambient light, when comparing a soft-copy image with the reproduced hard-copy image. The visual experiments were performed on the effect of the ambient lighting under mixed chromatic adaptation. It was found that human visual system is 40% to 60% adapted to CRT monitor's white point and the rest to the ambient light. This adaptation ratio itself was found to be independent of the luminance level of the ambient lighting for the portrait images. Practical method for appearance match between soft-copy and hard-copy is presented in this paper. This method is fundamentally based on a simple von Kries' adaptation model and in addition, takes into account of the human visual system's "partial adaptation."