Comparisons of relative size in pictorial spaces under the influence of depth cues were investigated. Using the staircase method, 40 participants adjusted the sizes of blank cards presented in the upper visual field to the size of playing cards presented in the lower visual field. During the presentation of the stimuli, pictorial depth cues were displayed in the computer screen and participants were asked to typify the strategy used to judge the perceived sizes. The horizon and the perspective line gradient contributed to the overestimation of the perceived size of blank cards in about 8 and 12%, respectively, and size comparisons were coherent with the constancy of size.
Relative size; horizon; visual perception; familiar size; pictorial depth cues
