Foreshortened tiles in paths converging on an observer viewing a picture: elevation and visual angle ratio determine perceived size

Abstract

Observers were shown wide-angle pictures of tiles on a ground plane and were asked about the aspect ratios of the tiles. The observers viewed the pictures from a fixed center of projection. Some of the tiles were in a path coming straight toward the observer. In one picture, the path came from the center of the picture, and in two others the path came from the left side of the picture (one from 30 degrees and one from 45 degrees to the left of the center, from the observer's point of view). The apparent aspect ratios were a function of the elevations of the tiles and the ratios of visual angles of the sides of the tiles. Judgments were identical for all three paths. The local slant of the picture surface was not a significant factor.