File:Grey square optical illusion.PNG

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Summary

Description An optical illusion. Square A is exactly the same shade of grey as square B. See demonstration.
Date Original in 1995, this file in January 2004
Source File created by Adrian Pingstone, based on the original created by Edward H. Adelson
Author Original by Edward H. Adelson, this file by Gustavb
Permission
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The copyright holder of this work allows anyone to use it for any purpose including unrestricted redistribution, commercial use, and modification.

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Date/TimeThumbnailDimensionsUserComment
current10:20, 24 May 2016Thumbnail for version as of 10:20, 24 May 20161,087 × 844 (143 KB)Avayakoptimized losslessly
21:13, 13 January 2008Thumbnail for version as of 21:13, 13 January 20081,087 × 844 (159 KB)Mahahahaneapneappngcrushed
03:54, 24 April 2007Thumbnail for version as of 03:54, 24 April 20071,087 × 844 (214 KB)Jrockleymuch larger version
00:41, 9 April 2007Thumbnail for version as of 00:41, 9 April 2007522 × 408 (70 KB)JrockleyPrepared for Wikipedia by Adrian Pingstone in January 2004, based on the [http://web.mit.edu/persci/people/adelson/checkershadow_illusion.html original] created by Edward H. Adelson. See also [http://en.wikipedia.org/wiki/Same_color

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