smalltalk
monkey business
There is a version of this were the grey looks colored because of the surrounding light.
An Optical Illusion: It's moving!
- Thread starter smalltalk
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There is a version of this were the grey looks colored because of the surrounding light.
Mrogreturns
The Ghost Who Posts
@Akka- could you possibly do me a favour and post the illusion with the labels A & B removed (i.e so that they are fully shaded). I would be interested to see the strength of the illusion when based solely on the misperception of shadow.
Akka
Moody old mage.
As you wish 
Mrogreturns
The Ghost Who Posts
Thanks
Certainly demonstrates that the different shading on the labels "A" & "B" isn't necessary to induce the illusion.
Certainly demonstrates that the different shading on the labels "A" & "B" isn't necessary to induce the illusion.
CrackedCrystal
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No one has posted the classic optical illusion yet....
CrackedCrystal
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CrackedCrystal what is happening in your illusion? I dont get it.
Akka, If something is in shadow wouldnt that make it darker as the light is not reaching it. That doesnt make sense to me.
It is quite amazing though. Are all the other squares different? Like the one diagonally to the left of B is that the same?
And if you remove the Pillar casting the shadow would there be 3 dark squares in a row as B is actuall not the lighter tone?
Akka, If something is in shadow wouldnt that make it darker as the light is not reaching it. That doesnt make sense to me.
It is quite amazing though. Are all the other squares different? Like the one diagonally to the left of B is that the same?
And if you remove the Pillar casting the shadow would there be 3 dark squares in a row as B is actuall not the lighter tone?
CrackedCrystal
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Look at the left of the picture. It seems there are three prongs to this object, but if you look at the right side, the base only has two prongs.
I figured everyone had seen this one before.
CrackedCrystal
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Mrogreturns
The Ghost Who Posts
We mispercieve square "B" as being in a shadow, consequently our perceptual system regards it as being darker than it really is. However, the square "A" (which is not in shadow) is actualy the same shade as "B".
So what we are presented with is two squares of the same shade but one is in a shadow and the other is not- the way our perceptual system resolves this problem is by regarding square "B" as being lighter in shade than square "A". So that is what we percieve.
The fact that the ilusio occurs even though we know there in no shadow and persists even when you demonstrate conclusivly that A & B are the same shows how rigid and stimulus-driven this system is.
@ Akka- another request! Could you change the shading of label "A" to match that of "B" and / visa versa? Sorry if it`s difficult- it would be interesting to see the effect though.
allan2
Gone Fishing
That shadow pic is truly amazing. I put it in Photoshop and "cut" everything but two small rectangles, one out of each square, and they were in fact the same shade! And yet they look VERY different in the picture.
Another thing you can do is blow up the entire pic by 1600%--so that you don't see the overall shadow effect, just the corner of one square at the top of the screen, and a corner of the other at the bottom. By not seeing the shadow effect, you see that they are the same shade.
I think also that it's not just the shadow, but the different colors of the surrounding squares (the "background" color) that aids the effect. (When you blow up the pic as I described, the squares are no longer "surrounded" in your view, so that diminishes the effect. Also, when you "cut" samples from the squares out and place them on a white background, you can judge their shades to be equal, as they both appear on an equal white background.)
P.S. I've read one time that "sunspots" would actually appear VERY bright to the eye if they were by themselves, but being surrounded by the much brighter photosphere of the Sun, they appear black! This may be a similar principle at work here.
Another thing you can do is blow up the entire pic by 1600%--so that you don't see the overall shadow effect, just the corner of one square at the top of the screen, and a corner of the other at the bottom. By not seeing the shadow effect, you see that they are the same shade.
I think also that it's not just the shadow, but the different colors of the surrounding squares (the "background" color) that aids the effect. (When you blow up the pic as I described, the squares are no longer "surrounded" in your view, so that diminishes the effect. Also, when you "cut" samples from the squares out and place them on a white background, you can judge their shades to be equal, as they both appear on an equal white background.)
P.S. I've read one time that "sunspots" would actually appear VERY bright to the eye if they were by themselves, but being surrounded by the much brighter photosphere of the Sun, they appear black! This may be a similar principle at work here.
Mrogreturns
The Ghost Who Posts
Yes that's true- its the same thing I was getting at when I noted the different shading on the labels, but the effect of the surrounding squares is much much stronger
Akka
Moody old mage.
Feeling like testing all possibilities ? ^^Originally posted by Mrogreturns
@ Akka- another request! Could you change the shading of label "A" to match that of "B" and / visa versa? Sorry if it`s difficult- it would be interesting to see the effect though.
Here is the one :
I just replaced the B with the A (copy-paste), it was really too hard to try to rewrite the letter
smalltalk
monkey business
straight lines:
Mrogreturns
The Ghost Who Posts
@Akka- cheers mate! Doesn`t effect the msil illusion, but introduces a new one!
The next thing would be to get rid of the shadow...... only joking.
The next thing would be to get rid of the shadow...... only joking.
Eastern Knight
Dragons!
whoa 
