Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Chundles

macrumors G5
Original poster
Jul 4, 2005
12,037
493
Have a go at this.

In the first picture, squares A and B are in fact the same colour.

You can see in the second picture, I opened it in Photoshop and dragged square B next to square A, I did not touch the colour in any way.

You can find the original illusion at www.killsometime.com
 

Attachments

  • illusion-1-1.jpg
    illusion-1-1.jpg
    24.1 KB · Views: 217
  • illusion-1.jpg
    illusion-1.jpg
    9.9 KB · Views: 130
Excellent!

You can also see this merely by holding a pen or a folded piece of paper (or something similar) to the screen so as to "bridge the gap" between the squares, and then you can see they are the same color.

Wicked....
 
Mr. Anderson said:
that's nothing that new - its well known that color is relative to those around it, at least from our perception of them.

Here's a really fun and crazy one.

http://www.patmedia.net/marklevinson/cool/cool_illusion.html

the fact that the green dot appears and then the pink ones disappear is totally nuts - when all that's going on there is a synchronized blinking of the pink dots...

D
I'd seen that one before. Very cool, though.

Apparently, many people are also able to look at a Dell and see something attractive... surely the best illusion yet!
 
Mr. Anderson said:
that's nothing that new - its well known that color is relative to those around it, at least from our perception of them.

Here's a really fun and crazy one.

http://www.patmedia.net/marklevinson/cool/cool_illusion.html

the fact that the green dot appears and then the pink ones disappear is totally nuts - when all that's going on there is a synchronized blinking of the pink dots...

D

Very nice!
 
jsw said:
I'd seen that one before. Very cool, though.

Apparently, many people are also able to look at a Dell and see something attractive... surely the best illusion yet!

or even look at Windows and see something usable and well done. :rolleyes: :cool:
 
Mr. Anderson said:
that's nothing that new - its well known that color is relative to those around it, at least from our perception of them.

Here's a really fun and crazy one.

http://www.patmedia.net/marklevinson/cool/cool_illusion.html

the fact that the green dot appears and then the pink ones disappear is totally nuts - when all that's going on there is a synchronized blinking of the pink dots...

D


I hadn't seen this one before, thanks for the link! I love these things... :)
 
Mr. Anderson said:
that's nothing that new - its well known that color is relative to those around it, at least from our perception of them.

Here's a really fun and crazy one.

http://www.patmedia.net/marklevinson/cool/cool_illusion.html

the fact that the green dot appears and then the pink ones disappear is totally nuts - when all that's going on there is a synchronized blinking of the pink dots...

D



maybe this one would go some way to explaining why (to me anyway) the lights on the Verrazano Narrows Bridge in NYC look green from afar, yet when you're on the bridge they are in fact regular, white lights.
 
evoluzione said:
maybe this one would go some way to explaining why (to me anyway) the lights on the Verrazano Narrows Bridge in NYC look green from afar, yet when you're on the bridge they are in fact regular, white lights.


hmm, not sure what the physics of that could be - but I'm inclined to guess that the spinning pink disc has more to do with the refresh rate of the the computer monitor and not the actual colors themselves. I'd like to see if you could recreate that thing physically and still see the same effects.

D
 
Mr. Anderson said:
hmm, not sure what the physics of that could be - but I'm inclined to guess that the spinning pink disc has more to do with the refresh rate of the the computer monitor and not the actual colors themselves. I'd like to see if you could recreate that thing physically and still see the same effects.

D

I don't think the thing with the bridge lights is the same phenomenon. That's probably related to the fact that white light contains all colors of light, but our eyes are most sensitive to green light. Far away from the lights, the air has greatly attenuated the strength of the light (at all colors) but green is still visible due to our eyes sensitivity to that color.

As for the pink dots illusion, our eyes have dual receptors, and red/green is one kind of receptor. After we stare at the cross for a moment the area of our eyes upon which the pink light is following has acclimated to the pink somewhat. If you look closely you'll notice that the "moving dot" is actually a rotating disappearing dot. When the dot disappears in a particular spot, your eyes see green because they sort of over compensate for the missing pink. It's similar to the way everything looks bluish when you take ski goggles off after wearing them all day. The reason the pink dots disappear is because your brain nearly completely acclimates itself to them. The human brain is very good at filtering constant sensations out. That's why you don't really notice noise in a room after you've been in it for a while. You also notice this when you walk into a room with a faint but noticeable smell. Unless it's REALLY strong, after a few minutes, you can't smell it anymore, but someone walking in from outside will still be able to.
 
Try this one. You need to focus on the picture and after a while an animal should appear, it helps if you tilt your head a little.

EDIT: Sorry can't attach the image.
 
Mr. Anderson said:
hmm, not sure what the physics of that could be - but I'm inclined to guess that the spinning pink disc has more to do with the refresh rate of the the computer monitor and not the actual colors themselves. I'd like to see if you could recreate that thing physically and still see the same effects.

D

I was skeptical too. Download the image and open it up in Preview. You can step through each frame at any speed. My guess is that pink (or maybe "pink on gray") burns into your sensors a bit, and so when it disappears there's an overaccumulation that we see as green. It apparently only has to do with peripheral vision, which is why you only see it when you stare at the plus sign in the center of the ring.

So its not a refresh rate thing. Don't know how you'd recreate it physically, except to have pink light bulbs? Might be a fun thing to build.
 
mduser63 said:
As for the pink dots illusion, our eyes have dual receptors, and red/green is one kind of receptor. After we stare at the cross for a moment the area of our eyes upon which the pink light is following has acclimated to the pink somewhat. If you look closely you'll notice that the "moving dot" is actually a rotating disappearing dot. When the dot disappears in a particular spot, your eyes see green because they sort of over compensate for the missing pink. It's similar to the way everything looks bluish when you take ski goggles off after wearing them all day. The reason the pink dots disappear is because your brain nearly completely acclimates itself to them. The human brain is very good at filtering constant sensations out. That's why you don't really notice noise in a room after you've been in it for a while. You also notice this when you walk into a room with a faint but noticeable smell. Unless it's REALLY strong, after a few minutes, you can't smell it anymore, but someone walking in from outside will still be able to.

More specifically, your eyes are adjusted to pink. When the pink goes away, the receptors return to 'normal' and you see green. It is an afterimage, like a flash of a camera. Pink is close to red, and Red/Green share a receptor as well as Yellow/Blue. This is why you do not see a reddish green or a yellowish blue. Yellow+Blue=Green, not a yellowish blue. Also, your eyes contain Black/White receptors to see depth and brightness of a color.

savar said:
I was skeptical too. Download the image and open it up in Preview. You can step through each frame at any speed. My guess is that pink (or maybe "pink on gray") burns into your sensors a bit, and so when it disappears there's an overaccumulation that we see as green. It apparently only has to do with peripheral vision, which is why you only see it when you stare at the plus sign in the center of the ring.

So its not a refresh rate thing. Don't know how you'd recreate it physically, except to have pink light bulbs? Might be a fun thing to build.

Actually, it is because the majority of the color receptors are in the center of your eye. When you look at the + sign, you are concentrating the most color receptors at the pink dots, and therefore, allowing the most adjustment to pink as possible before the dot disappears and the afterimage of green is produced. And you could recreate it with lightbulbs, however having a background that you don't see ANYTHING on after the light goes out would be hard, because the lightbulb being present may negate some of the effects of this illusion, although the illusion overall would still work.
 
mpw said:
Try this one. You need to focus on the picture and after a while an animal should appear, it helps if you tilt your head a little.

EDIT: Sorry can't attach the image.

I have only one thing to say to your post (not you):
Linkety
 
I think the green dot phenomenon has been pretty well explained here. As for why the pink dots disappear, that's because of Troxler fading. You can see the effect even in a static image: take a look at this one. Stare at the center long enough, and it will fade into the background. If you're skeptical about screen refresh rates, you can download the file and print it out -- it's a static GIF.

We've written an article on the Troxler effect at Cognitive Daily.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.