Header logo is

Perception of Planar Shapes in Depth

2001

Poster

ei


We investigated the influence of the perceived 3D-orientation of planar elliptical shapes on the perception of the shapes themselves. Ellipses were projected onto the surface of a sphere and subjects were asked to indicate if the projected shapes looked as if they were a circle on the surface of the sphere. The image of the sphere was obtained from a real, (near) perfect sphere using a highly accurate digital camera (real sphere diameter 40 cm; camera-to-sphere distance 320 cm; for details see Willems et al., Perception 29, S96, 2000; Photometrics SenSys 400 digital camera with Rodenstock lens, 12-bit linear luminance resolution). Stimuli were presented monocularly on a carefully linearized Sony GDM-F500 monitor keeping the scene geometry as in the real case (sphere diameter on screen 8.2 cm; viewing distance 66 cm). Experiments were run in a darkened room using a viewing tube to minimize, as far as possible, extraneous monocular cues to depth. Three different methods were used to obtain subjects' estimates of 3D-shape: the method of adjustment, temporal 2-alternative forced choice (2AFC) and yes/no. Several results are noteworthy. First, mismatch between perceived and objective slant tended to decrease with increasing objective slant. Second, the variability of the settings, too, decreased with increasing objective slant. Finally, we comment on the results obtained using different psychophysical methods and compare our results to those obtained using a real sphere and binocular vision (Willems et al.).

Author(s): Wichmann, FA. and Willems, B. and Rosas, P. and Wagemans, J.
Journal: Journal of Vision
Volume: 1
Number (issue): 3
Pages: 176
Year: 2001
Month: December
Day: 0

Department(s): Empirical Inference
Bibtex Type: Poster (poster)

Digital: 0
DOI: 10.1167/1.3.176
Event Name: First Annual Meeting of the Vision Sciences Society (VSS 2001)
Event Place: Sarasota, FL, USA
Organization: Max-Planck-Gesellschaft
School: Biologische Kybernetik

Links: Web

BibTex

@poster{1151,
  title = {Perception of Planar Shapes in Depth },
  author = {Wichmann, FA. and Willems, B. and Rosas, P. and Wagemans, J.},
  journal = {Journal of Vision},
  volume = {1},
  number = {3},
  pages = {176},
  organization = {Max-Planck-Gesellschaft},
  school = {Biologische Kybernetik},
  month = dec,
  year = {2001},
  month_numeric = {12}
}