The result of this reduction is that the last few pairs are barely viewable. This reduction in contrast decreases the image's signal to noise, so provides a test of a system's noise sensitivity. Accurate recovery of the ball's boundary is a challenge. The railroad track is highly ambiguous, with its repeated pattern of basically identical vertical bars. Heavy shadowing in the foreground hides the grass texture.
Sky is seen through the tree branches.
The trees have large disparity with respect to the ground and building behind them. The sky presents a false-positive challenge, the shadowed ground is rather featureless, the tree trunks are highly varying in texture, and structurely quite narrow. Movement between images was about a centimeter. The successive data sets have increasing baseline, so provide a test of a system's ability to hndle larger disparities. The ground is covered with wild grass.