The strawberries in this photo are blue


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I abandoned my efforts to become a neuroscientist a couple years ago. Can someone who didn’t fill us in here? I can’t even recall my lectures on the on-off zones of photoreceptors and even that seems too low-level to explain this. What cortical processing is responsible for this relativistic shift in hue perception?


Not very red!



For context, this is what that color of strawberry would look like in an image where the rest of the pixels aren’t tinted blue:


What do they taste like? I am not very partial to red strawberries, so these might be an improvement.


For his next trick, Mark will convince us he’s holding up 5 fingers instead of 4.



It is all gestalts. Colors shift according to what they are near by - it is relative.

Using the eyedropper and CMYK, everything is high Cyan, until you get to the “red” parts, which shift with the cyan dipping, and the values closer to grey in most areas.

So, there you have it - in a world of cyan, when a less cyan grey is the closest thing you have to red, red is what you see.


In my brain, I hear that in a dramatic movie trailer voice.


Is the suggestion that I am imagining the red in the view point just because “strawberries are red” is in my mind?.
a circle cut out of a card, masking the rest of the image, it still looks reddish to me.


How about this: put a blue filter on a picture. People can still figure out what it is.


I’m too distracted by the overexposure to care whether there’s any actual red pixelation, honestly.

Perhaps that’s why I was never even tempted to discuss the dumb ‘dress’ that went viral a few years back; the fact that the one version of the image was so poorly lit didn’t necessitate any need for debate.

That the brain plays tricks with our vision based upon the amount of light we are exposed to is nothing new; good artists reply upon that quirk of perception, and use it to their advantage.


Sort of like how when we’d watch black and white tv as kids, we’d sorta see colors. The grass was “green”, the sky was “blue”, people were flesh toned. The human brain and eye seems pretty good at filling in or correcting information. Which is how optical illusions work.


I recommend you get a copy of Oliver Sacks’ book “An Anthropologist on Mars” and read his case study “The Case of the Colour-blind Painter”. It’s not his best book, but that particular study, and the one on Temple Grandin, are both quite good.

Sacks says Edwin H. Land figured out how color vision works (although certain research results make me think Land was only 2/3 right). Certainly, it does not work the way I was taught in school - the eye does not read wavelengths or frequencies as colors, that’s complete nonsense and easily disproven by tricks like this.

Sacks talks about the partial blindness he himself suffered from eye cancer here.


That’s why when you paint you want to develop the overall picture, since color perception is so context-sensitive.


It’s why things look the same color at dawn, noon, or sunset.


That’s how I knew that Wilma and Pebbles Flintstone both had red/orange hair!


This reminds me of an article I read long ago, saying if you lived under a red dwarf sun, you would very quickly stop noticing the color shift - but it would still be gloomy.


And your super-powers wouldn’t exist, either.


Would too.