ECVP 2007 Abstract

Cite as:
Vergeer M L T, van Lier R, 2007, "Breaking down the Benary Cross" Perception 36 ECVP Abstract Supplement

Breaking down the Benary Cross

M L T Vergeer, R van Lier

We present large reductions of lightness differences in the Benary Cross by breaking down its global appearance and, with that, changing the perceived figure - background relations. We start with the traditional Benary configuration in which a grey triangle superimposed on a black cross appears lighter than a grey triangle juxtaposed to that cross, even though the triangles are surrounded by the same amount of black and white. In our experiment, the global shape of the cross is manipulated by creating triangular notches at corresponding positions along the contours of each bar of the cross (the local surroundings of the patches stay the same). As a result, the previously superimposed triangle now appears juxtaposed to the indented cross, revealing a reduction of lightness differences. Subsequently, local differences between both patches are nullified by shifting the notches along the contours of the cross, which leads to a further decrease of lightness differences. Finally, after rotating the resulting image by 45°, lightness differences are even reversed. Experimental data confirm the above observations.

[MV is supported by a grant from the Netherlands Organisation for Scientific Research (NWO).]

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