Pages: [1]   Go Down

Author Topic: Great illusion  (Read 4501 times)

tom b

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1471
    • http://tombrown.id.au
Great illusion
« on: August 21, 2011, 02:22:29 am »

You won't believe your eyes in this video.

Cheers

Tom
Logged
Tom Brown

feppe

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2906
  • Oh this shows up in here!
    • Harri Jahkola Photography
Re: Great illusion
« Reply #1 on: August 21, 2011, 05:34:16 am »

Haven't seen this done in real life like this before, really nice!

Eric Myrvaagnes

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 22814
  • http://myrvaagnes.com
    • http://myrvaagnes.com
Re: Great illusion
« Reply #2 on: August 21, 2011, 09:05:41 am »

Haven't seen this done in real life like this before, really nice!
Likewise! Much more convincing than the usual 2D illustrations where you have to use the eyedropper to verify it.
Logged
-Eric Myrvaagnes (visit my website: http://myrvaagnes.com)

aduke

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 446
Re: Great illusion
« Reply #3 on: August 21, 2011, 01:12:24 pm »

A nice illustration of the illusion. It would have been even more convincing if the squares had been shown to be completely opaque.

Alan
Logged

tom b

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1471
    • http://tombrown.id.au
Re: Great illusion
« Reply #4 on: August 21, 2011, 04:25:24 pm »

Here is a screen grab from the illusion. I can't see any transparency.



Cheers,
Logged
Tom Brown

aduke

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 446
Re: Great illusion
« Reply #5 on: August 21, 2011, 05:43:30 pm »

It does appear from that frame that there is none. But this is an illusion, after all.

Alan
Logged

tom b

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1471
    • http://tombrown.id.au
Re: Great illusion
« Reply #6 on: August 21, 2011, 06:20:06 pm »

This is what an optical illusion is. The only thing that is tricking us is our brain.

I copied the image on the link's page and pasted it into Photoshop. I then copied the two squares and moved them to the right. The result is shown below:



Try it for yourself.

Cheers,


Logged
Tom Brown

Eric Myrvaagnes

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 22814
  • http://myrvaagnes.com
    • http://myrvaagnes.com
Re: Great illusion
« Reply #7 on: August 21, 2011, 09:06:35 pm »

And just to verify, I popped this image into Photoshop and placed the hand just to the left of each of the A's and B's and read off the RGB values from the "Info" panel.

As expected, for both A tiles, I read R=G=B=139. But for the left hand B tile (the one still on the board, in the shadow) I read R=B=G=139, while for the right hand B tile (the one off to the side) I get R=G=B=139, which is 'obviously' much higher than 139.  ???

Conclusion: You can fool some of the people all of the time, but you can only fool Photoshop some of the time.  ;)
Logged
-Eric Myrvaagnes (visit my website: http://myrvaagnes.com)

BobDavid

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3307
Re: Great illusion
« Reply #8 on: August 26, 2011, 09:30:04 am »

Neat
Logged

BernardLanguillier

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 13983
    • http://www.flickr.com/photos/bernardlanguillier/sets/
Re: Great illusion
« Reply #9 on: August 28, 2011, 05:46:54 pm »

Nice!

It is a great confirmation of the remarkable inability of our brain to assess realistically absolute values, yet alone to remember them.

Audiophiles wouldn't like it! :)

Cheers,
Bernard
Pages: [1]   Go Up