Viewing comfort with stereoscopic pictures : an experimental study on the subjective effects of disparity magnitude and depth of focus

— A wide range of binocular disparity (0–140 arcmin) and depth-of-focus (DOF) conditions (resolution of non-fixated motif, 1–23 cpd) were presented via stereoscopic slides to 12 non-expert subjects. Viewing comfort was evaluated by a standardized assessment procedure (CCIR Recommendation 500). Results confirm the traditional threshold of 70 arcmin for disparities. Larger disparities lead to a marked drop in comfort ratings unless critical parts of the image are heavily blurred. In this case, even disparities of 140 arcmin are tolerated. Picture luminance (47 vs. 17 cd/m2) had no influence. The high consistency of the observed response patterns suggests a stable perceptual mechanism.