Visual Psychology...a stunner

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Visual Psychology...a stunner

Postby Matt. K on Sat Dec 04, 2004 6:57 pm

Seeing as how this is my 500th post I thought I would drop a stunner on the forum...and this is my favourite subject.
The enclosed image shows 2 squares marked A and B...they are the same tone of grey!
Your eyes are weak little instruments that lie to you all the time.
Don't believe me? Load the image into Photoshop and copy square A.
Paste it back and move it next to square B
There you go.
http://www.pbase.com/matt_k/image/37091608
Last edited by Matt. K on Sat Dec 04, 2004 9:42 pm, edited 2 times in total.
Regards

Matt. K
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don't trust your eyes ...

Postby christiand on Sat Dec 04, 2004 7:00 pm

Hi,

this is an excellent example of how you cannot trust your eyes
when it comes to assess how bright or dark something is.
It also illustrates very well how our brains interpret light.

Cheers
CD
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Postby Greg B on Sat Dec 04, 2004 8:45 pm

Astonishing Matt, and a fitting exercise for your 500th post.

(If only there was a way to get both squares right in the middle :) )

Congratulations. I enjoy your provocative and insightful comments and observations. Even when you are giving me some what for.

cheers
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Postby bago100 on Sat Dec 04, 2004 9:23 pm

Hatt

If you copy the square exactly, then the illusion does what you say.

If you cut the square slightly larger than the original, except for the top edge that is not part of the image, the colours do not match.

As the late Julius Sumner Miller would have said "Why is that so?"

Congratulations on your 500th post!
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Postby Greg B on Sat Dec 04, 2004 10:02 pm

I opened the image up in photoshop and checked the two squares with the eyedropper. I knew they would be the same (cos Matt said so), but there is no substitute for empirical evidence.
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Postby Killakoala on Sun Dec 05, 2004 12:55 pm

That's wierd.
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Postby mudder on Sun Dec 05, 2004 5:28 pm

Wow,
Goes to show how powerfully our brains interpret data and tell our eyes what they see...

Good find too...

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Postby Deano on Mon Dec 06, 2004 3:06 pm

I did a search (God bless Google) and here are a few more in the same vein with explanations. Amazing!

http://web.mit.edu/persci/gaz/#

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Postby Glen on Mon Dec 06, 2004 4:52 pm

Amazing Matt, do you know anywhere I could get a good set of eyes which could tell they were the same grey?
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Postby Onyx on Mon Dec 06, 2004 5:28 pm

Slip on a welder's mask. Then both squares will be the same shade... ;)
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Postby atencati on Tue Dec 07, 2004 6:09 am

along the welding mask line...if you squint your eyes ( a la aperture) the squares at soome point will appear the same......

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Postby PlatinumWeaver on Wed Dec 08, 2004 1:11 am

*blinks*
:shock:
*blinks*
:o

That's unbelievable...
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