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  1. #1
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    Default Illusion or not?!

    Apparently, there is no red in this picture.

    If you zoom in, the red disappears.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  2. #2
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    Placitas, New Mexico, USA
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    Default Re: Illusion or not?!

    I read about this somewhere and the explanation was we see red for the can because that is the color we expect it to be.

  3. #3
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    Default Re: Illusion or not?!

    I think there's a bit of red (actually, shades of red) in there that shows clearer the more you zoom out.

  4. #4
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    Default Re: Illusion or not?!

    Quote Originally Posted by Boy View Post
    I think there's a bit of red (actually, shades of red) in there that shows clearer the more you zoom out.

    I disagree Boy to me GP's reply seems to make sense but I understand what you are saying.
    Larry a.k.a wizard509

    Never give up. You will never fail, but you may find a lot of ways that don't work.

  5. #5
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    Default Re: Illusion or not?!

    print it out and look at it close under strong natural light - no red

    the brain is doing it's usual thing of interpreting what the eyes send it, and in this instance getting it wrong; optical illusion
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  6. #6
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    Default Re: Illusion or not?!

    I opened the image in XDP, zoomed in and saw variations of hints of red (and other colors) in the white vertical bars. With the eyedropper, I also checked the black bars and they also have hints of red (and other colors). I imagine this was done on purpose to create the effect of a red can.

  7. #7
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    Default Re: Illusion or not?!

    I just tried that and I can get no red values for H or S above zero and a V value of around 99.6% - if you did better be interested to see

    personally I think that is artifact, since the black will not be pure black and therefore there will be red frequencies there in the mix 'bleeding out'

    interestingly I also tried it in affinity photo which, like photoshop, samples the pixels on zoom so they stay artifact free - not a hint of red anywhere when zoomed right in...
    Last edited by handrawn; 02 June 2022 at 12:41 PM. Reason: pixes should not be sampled [here]
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  8. #8
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    Default Re: Illusion or not?!

    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.

  9. #9
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    Default Re: Illusion or not?!

    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?
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  10. #10
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    Default Re: Illusion or not?!

    @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

    Click image for larger version. 

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ID:	132133Click image for larger version. 

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    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
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