Depth of field affects perceived depth in stereographs

Although it has been reported that depth of field influences depth perception in nonstereo photographs, it remains unclear how depth of field affects depth perception under stereo viewing conditions. We showed participants stereo photographs with different depths of field using a Wheatstone stereoscope and a commercially available 3D TV. The depicted scene contained a floor, a background, and a measuring probe at different locations. Participants drew a floor plan of the depicted scene to scale. We found that perceived depth decreased with decreasing depth of field for shallow depths of field in scenes containing a heightin-the-field cue. For larger depths of field, different effects were found depending on the display system and the viewing distance. There was no effect on perceived depth using the 3D TV, but perceived depth decreased with increasing depth of field using the Wheatstone stereoscope. However, in the 3D TV case, we found that the perceived depth decreased with increasing depth of field in scenes in which the height-in-the-field cue was removed. This indicates that the effect of depth of field on perceived depth may be influenced by other depth cues in the scene, such as height-in-the-field cues.