File:Grey square optical illusion.PNG

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In other languages

Alemannisch ∙ العربية ∙ беларуская (тарашкевіца) ∙ български ∙ বাংলা ∙ català ∙ нохчийн ∙ čeština ∙ dansk ∙ Deutsch ∙ Ελληνικά ∙ English ∙ British English ∙ Esperanto ∙ español ∙ eesti ∙ euskara ∙ فارسی ∙ suomi ∙ français ∙ Frysk ∙ galego ∙ Alemannisch ∙ עברית ∙ hrvatski ∙ magyar ∙ հայերեն ∙ Bahasa Indonesia ∙ Ido ∙ italiano ∙ 日本語 ∙ ქართული ∙ 한국어 ∙ lietuvių ∙ македонски ∙ മലയാളം ∙ Bahasa Melayu ∙ norsk bokmål ∙ Plattdüütsch ∙ Nederlands ∙ norsk nynorsk ∙ norsk ∙ occitan ∙ polski ∙ prūsiskan ∙ português ∙ português do Brasil ∙ română ∙ русский ∙ sicilianu ∙ Scots ∙ slovenčina ∙ slovenščina ∙ српски / srpski ∙ svenska ∙ தமிழ் ∙ ไทย ∙ Türkçe ∙ татарча / tatarça ∙ українська ∙ vèneto ∙ Tiếng Việt ∙ 中文 ∙ 中文（中国大陆） ∙ 中文（简体） ∙ 中文（繁體） ∙ 中文（马来西亚） ∙ 中文（新加坡） ∙ 中文（臺灣） ∙ 中文（臺灣） ∙ +/−

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
(Reusing this file)

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File history

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	Date/Time	Dimensions	User	Comment
current	10:20, 24 May 2016	1,087 × 844 (143 KB)	Avayak	optimized losslessly
	21:13, 13 January 2008	1,087 × 844 (159 KB)	Mahahahaneapneap	pngcrushed
	03:54, 24 April 2007	1,087 × 844 (214 KB)	Jrockley	much larger version
	00:41, 9 April 2007	522 × 408 (70 KB)	Jrockley	Prepared 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