Samenvatting
This study investigated the luminances to perceive red (642mm), green (521mm), and blue (408mm) ad nine visual, angles ranging from over 1 to 21 sec, of are diam. Monocular, focally measurements were made by the method of constant stimuli at exposures of 44 and 700 msec. duration. Three colour-normals served as observers. The results show that, with sufficient luminance. These hues can be seen even for stimuli as small as 0,35 min. of are diam.