Perception of artificial stereoscopic stimuli from an incorrect viewing point

The present study investigates the distortions in the perception of artific ial stereoscopic displays seen from an inappropriate distance and/or orient ation. Stereoscopic displays represent 3-D information correctly, provided they are seen from the correct station point. The viewing point may differ from the correct station point in its distance or in its orientation to the screen. These differences lead to distortions that can be predicted mathem atically. However, the perceptual function may be different from the predic tions, since people may possibly compensate for the distortions. To test th e degree of this compensation, participants saw anaglyphic stereoscopic sti muli that showed angles in the horizontal plane, and their perception of th e configuration was tested for various orientations and distances. The esti mates were compared with the values predicted from the mathematical functio ns, and participants' virtual positions were reconstructed via nonlinear re gressions. The analyses revealed a moderate compensation for viewing orient ations and a systematically overestimation of the viewing distances. These results indicate that people compensate partially for distortions in stereo psis, given that the relevant information is available.