Can't believe my eyes! (Optical illusion.)

[ColinJ]

I just found something online which I found unbelievable, so I did what was suggested and imported the picture into a drawing package and checked... the statement is correct! Take a look at it ...

I added the bar labelled 'C' to check the incredible assertion that the squares labelled 'A' and 'B' are actually the same shade of grey!

Don't believe me?

I'll drag it over for you ...

I STILL can't get my head round it!!!

 

[classic33]

Bar C, gets lighter as you near it's base though.

 

[ColinJ]

That's the point - it LOOKS as if it does, but that is the same bar as in the first picture. It is one solid shade of grey with no changes in it. All I did was pick it up and drag it over! The bar and the squares all have RGB values of #787878.

 

[Seevio]

It really doesn't. Mask out the background so you can only see the bar. (your thumbs will do if you are viewing on a phone)

 

[Beebo]

Isn’t the brain a clever thing.
It knows that the lighter square in the shade should be lighter, so convinces us that what we see is actually wrong.

 

[Rezillo]

https://www.illusionsindex.org/ir/checkershadow

or to quote the easier bit of it:

"While there is a shadow depicted as falling across the checkerboard, there isn't really a shadow there—for Adelson's Checker-Shadow illusion is just a picture of a shadow. And this is what causes the illusion. Adelson’s Checker-Shadow Illusion is therefore the result of a failure of our inductive inferences to line up with the world. Using premises based on sensory evidence, perceived lighting conditions, and previous experiences, our visual system arrives at a false conclusion".

 

[ColinJ]

I've just masked out a lot of the picture and suddenly the squares look the same shade!

https://www.illusionsindex.org/ir/checkershadow

or to quote the easier bit of it:

"While there is a shadow depicted as falling across the checkerboard, there isn't really a shadow there—for Adelson's Checker-Shadow illusion is just a picture of a shadow. And this is what causes the illusion. Adelson’s Checker-Shadow Illusion is therefore the result of a failure of our inductive inferences to line up with the world. Using premises based on sensory evidence, perceived lighting conditions, and previous experiences, our visual system arrives at a false conclusion".

Thanks - that looks an interesting site!

 

[MontyVeda]

How can i trust my eyes after this?

 

[ColinJ]

How can i trust my eyes after this?

I think that every time I see the current president of the USA!

(And I will do a double-take when Boris becomes the next PM too ...)

 

[ColinJ]

I have a game called 'Color Puzzle' on my phone which is based on lining up squares of various shades. I've noticed that the squares seem to change colour as they are moved about relative to each other.

 

[classic33]

How can i trust my eyes after this?

Not everything is black & white though.

 

[Ming the Merciless]

Doesn't work for me don't know why

 

[ColinJ]

Doesn't work for me don't know why

Are you saying that the 2 squares both look the same shade of grey to you then?

 

[Ming the Merciless]

Are you saying that the 2 squares both look the same shade of grey to you then?

Yes

 

[presta]

View: https://www.youtube.com/watch?v=DkVOIJAaWO0