The threshold of stereopsis in the presence of differences in magnification of the ocular images.

A comparison between 100 percent correct response thresholds of stereopsis for nine subjects measured with and without viewing using a 33 percent difference in ocular image magnification is presented. Two subjects performed threshold settings, using the method of adjustments, with 1, 5, 10, 15, and 33 percent magnification differences. The extent of the increase explains reports of stereopsis in corrected unilateral aphakia.