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Topic: Optical Illusion  (Read 1719 times)

Offline nicolaievich

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Optical Illusion
on: December 22, 2005, 10:52:25 PM
Take a look at this. I couldn't believe it until I check it out using an image editor.

Click the hyperlink https://upload.wikimedia.org/wikipedia/commons/9/91/Optical.greysquares.arp.jpg to view the image.

The A and B squares have the same colour  :o

Offline lagin

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Re: Optical Illusion
Reply #1 on: December 23, 2005, 05:13:58 AM
I don't get it.  How can they be the same color??
Christians aren't perfect; just forgiven.

Offline contrapunctus

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Re: Optical Illusion
Reply #2 on: December 23, 2005, 05:21:54 AM
yeah block off each square so that you only see a small portion of each square and they are the same.
Medtner, man.

Offline Siberian Husky

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Re: Optical Illusion
Reply #3 on: December 23, 2005, 08:24:49 AM
use two fingers and cover the letters A and B...and focus in the middle of the two squares..they are indeed the same color..and i indeed wasted 30 seconds of my life
(\_/)
(O.o)
(> <)

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Offline Dazzer

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Re: Optical Illusion
Reply #4 on: December 23, 2005, 08:30:32 AM
just note that the squares around B are also in the shadow, and hence , darker.

Offline prometheus

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Re: Optical Illusion
Reply #5 on: December 23, 2005, 06:14:17 PM
We don't see absolute colours and darkness/lightness. We see relative ones. Something is dark when it is compared with light.

So square B is light, because there are dark squares around it. Square A is light because there are dark squares around it.


The fact that they are both the same colours doesn't matter. Our eyes, or rather brains, are blind to that. We don't measure, we compare.
"As an artist you don't rake in a million marks without performing some sacrifice on the Altar of Art." -Franz Liszt

Offline nicolaievich

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Re: Optical Illusion
Reply #6 on: December 23, 2005, 06:40:32 PM
That's right, but the important fact is that our brain can be deceived very easily

Offline lagin

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Re: Optical Illusion
Reply #7 on: December 24, 2005, 04:40:51 PM
Oh boy! Oh boy!  I got it.  I see it now too.  I'm excited.  But unlike Husky, I have wasted at least 2 minutes of my life, lol.
Christians aren't perfect; just forgiven.

Offline tompilk

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Re: Optical Illusion
Reply #8 on: December 25, 2005, 04:05:07 PM
That's amazing... we need more of the optical illusion things... the same puzzles keep coming up... but this one is original (i think)...  ;D
Working on: Schubert - Piano Sonata D.664, Ravel - Sonatine, Ginastera - Danzas Argentinas

Offline quantum

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Re: Optical Illusion
Reply #9 on: December 26, 2005, 10:24:43 PM
I like stuff like this. 
Made a Liszt. Need new Handel's for Soler panel & Alkan foil. Will Faure Stein on the way to pick up Mendels' sohn. Josquin get Wolfgangs Schu with Clara. Gone Chopin, I'll be Bach

Offline I Love Xenakis

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Re: Optical Illusion
Reply #10 on: December 26, 2005, 10:31:32 PM
(\_/)
(O.o)
(> <)


Lau is my new PF hero ^^

Offline mycrabface

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Re: Optical Illusion
Reply #11 on: December 27, 2005, 04:02:30 PM
yeah block off each square so that you only see a small portion of each square and they are the same.
WOT?
La Campanella Freak

Offline mycrabface

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Re: Optical Illusion
Reply #12 on: December 27, 2005, 04:05:41 PM
WHAT? I'm not wearing glasses.. Can't see a thing.. Anyway I don't understand as I am extremely stuuuupiddd... someone exxxplainnn pllloperly pleeeessseee.. seriously.. im stupid..
La Campanella Freak

Offline pianorama

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Re: Optical Illusion
Reply #13 on: December 29, 2005, 06:44:46 AM
I have actually seen that before in an optical illusion book.... It freaked me out when I covered all the other squares. Freaky....

Offline mycrabface

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Re: Optical Illusion
Reply #14 on: December 29, 2005, 03:28:14 PM
Cover which squares with what fingers and look at where??
La Campanella Freak

Offline jas

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Re: Optical Illusion
Reply #15 on: December 31, 2005, 01:21:18 PM
Cover all the squares but A and B. And cover up the letters themselves, too.
Or if you're really pedantic you could do what I did and copy it onto a paint programme and delete everything else! They are the same colour. It's so strange.

Jas

Offline ted

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Re: Optical Illusion
Reply #16 on: January 04, 2006, 09:45:18 AM
A few months ago, my algorithm to produce abstract art came up with the following picture:

https://photobucket.com/albums/c66/Oso1138/?action=view&current=chromostereopsis.jpg

To me, the red oval appears sunken into the screen. Several people, however, did not see the illusion at all, but only a flat picture of what could be a sunken oval. I wrote to a Japanese expert who has a site of optical illusions and he replied saying it was an example of chromostereopsis. Some people see it but most do not. Some even see red in front of other colours. I see it myself in the chatroom when people use different colours for their text, but when I asked others present, I was in a minority.
"Mistakes are the portals of discovery." - James Joyce

Offline nicolaievich

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Re: Optical Illusion
Reply #17 on: January 04, 2006, 09:10:33 PM
A few months ago, my algorithm to produce abstract art came up with the following picture:

https://photobucket.com/albums/c66/Oso1138/?action=view&current=chromostereopsis.jpg

To me, the red oval appears sunken into the screen. Several people, however, did not see the illusion at all, but only a flat picture of what could be a sunken oval. I wrote to a Japanese expert who has a site of optical illusions and he replied saying it was an example of chromostereopsis. Some people see it but most do not. Some even see red in front of other colours. I see it myself in the chatroom when people use different colours for their text, but when I asked others present, I was in a minority.

I think I can see what you see  8)
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