Illusion or not?!

[Boy]

Zooming in and just looking at it with the naked eye, I can see the slight color variations, especially in the white bars. Slowly zooming out, the white turns to pink and finally to red. Look at part of the thumb and some reflections on the foreground, they're also red.

[gwpriester]

Here's a larger version. I think the illusion might have something to do with the blue green colors reacting to the black.

Because otherwise, why would our brains not see the same thing if the image was black and white or grayscale?

[handrawn]

@boy

yes I can see very slight red - it is espcially clear in the affinity photo zoom because it is designed for photo editing in a way xara is not - both these screenshots are of the exact same file at the exact same pixel size



like I said this is artifact, it has nothing at all to do with the illusion, which is dependent on how the brain filters and decodes the colour frequencies it receives

so I was wrong to say there were not there in the affinity photo zoom, sorry... they are scant is all I can say in feeble excuse, and as far as I can tell only present near the green which would make sense as artifacts, the rest of the bars seem clear as day

[handrawn]

yep, obviously looked too far away from the green first time round



even if it were not artifact that would never be visible at zoom out

as a designer gary may have studied the way putting two colours together can alter the colour you see one as, or even both, as opposed to when they are seperate - this is really a special case of the same thing....

[Acorn]

If you isolate a section that appear to be all red, it is actually black.
Your eyes are influenced by the complementary cyan adjacent to the black to render red.
If you invert all the colours you see red/white in place of cyan/black and the illusion disappears as you cannot see anything green anywhere.
To make it work you would probably need a red/black combo.



Acorn

[handrawn]

How do you know it's just artifact?

can't be sure - but it is so scant it will have no bearing whatsoever on the way the brain interprets the colouration of that I am sure

@Dan and Acorn way to go - I should dig out my art college theory notes maybe, if I still have them, but there is a ton of stuff on the web about colour perception...

[DanFelix]

Possibly the high presence of cyan. I would like to see it without the cyan and see if the eye still perceives the red. I suspect that anyone who has never seen a Coke can would still see red due to the high presence of cyan. Cyan is created from B and G light, depleting those cones but not the red cones. You can see this effect when staring at a color and then looking at a neutral density image.

[Boy]

@boy

yes I can see very slight red - it is espcially clear in the affinity photo zoom because it is designed for photo editing in a way xara is not - both these screenshots are of the exact same file at the exact same pixel size



like I said this is artifact, it has nothing at all to do with the illusion, which is dependent on how the brain filters and decodes the colour frequencies it receives

so I was wrong to say there were not there in the affinity photo zoom, sorry... they are scant is all I can say in feeble excuse, and as far as I can tell only present near the green which would make sense as artifacts, the rest of the bars seem clear as day

How do you know it's just artifact?

I don't know how the effect of a red can has been created but I can imagine it has to do with the use of all these subtle color variation, the vertical bars and, as Gary suggests, the green color. However, I don't believe we see red only because our mind expects to see red because it's a Coke can (this aside from the fact that the brand also comes in silver and black cans).

[gwpriester]

Using DP+ palette from photo, this is what I get. The pink and red are the start of the regular Xara palette.

[handrawn]

good one gary