ABSTRACT Stereoacuity has been measured at various luminance difference levels and also at the isoluminance point, where the target and the background have equal luminances. The results of the experiment show that acuity at isoluminance is three times worse than the value obtained when there is maximum contrast between target and background. Possible reasons for these findings were investigated. Results of control experiments show that neither chromatic aberration nor defective accomodative response could be responsible for this finding.
Osuobeni et al. (Mon,) studied this question.