The Neural Control of Vision
P. Ongoing Research

Figure 16-3 shows the procedure when shading cues are added enabling us to assess performance when all three cues, motion parallax, disparity and shading, were presented separately or in various combinations. The left of the figure shows the display in three dimensions. A separate display was presented to each eye through the stereoscope as shown on the right of the figure. By virtue of fusing the two images a single display appeared. In this case a discrimination task was used in which one of the four truncated pyramids appeared at a greater depth. The depth difference made visible by virtue of the parallax, disparity, and shading cues presented together or separately was systematically varied enabling us to generate psychometric functions.