1995 Volume 79 Issue 2 Pages 101-107
It is well known that perceived color is not determined by the photometric values but instead depends on the surrounding pattern and the adapting condition of the eye. It is important that we know how color in complex patterns appears because the scenes we usually see are complicated. In this study we estimated the surround effect for appearance of achromatic color with two and four surrounds by using a new matching method that gives us the equiluminance of the simple uniform surround. The magnitude of surround effects of plural stimuli can be qualitatively described by the equivalent luminance. The results show that the average luminance of surround stimuli cannot explain the total surround effects of plural stimuli, but the spatial additivity of surround effects depends on the stimulus conditions. In addition, some characteristics of the surround effects differ between conditions with gap and conditions without gap. The spatial additivity of surround effects in the present study can be expressed by the summation of the luminance values of each surround weighted as a function of the luminance of a central patch.
