The optical-geometrical illusion "corner Poggendorff" re-examined

In 1988 Greene noted, if a straight pair of obliques are drawn outside of two orthogonal lines, the segments appears to be angled slightly one relative to the other. This illusion, designated as "corner Poggendorff" is different from the Poggendorff effect (the two obliques seem to lie on a parallel path). The results of the present experiments (N = 76 students) suggest that the general conditions for the corner Poggendorff are similar to those for the Judd illusion.