The brightness perception under shadow condition is investigated using the checker shadow illusion image in this research. By conducting the psychophysical experiment, brightness of grey patches under shadow and outside of shadow were evaluated. All in all, a patch under shadow appears 1.9 times brighter in average than the patch having the same luminance placed outside of the shadow. The effect becomes stronger as the shadow becomes darker.
Publisher
THE KOREAN INSTITUTE OF ILLUMINATING AND ELECTRUCAL INSTALLATION ENGINEERS,CHINA ILLUMINATING ENGINEERING SOCIETY,THE ILLUMINATING ENGINEERING INSTITUTE OF JAPAN