Diclaimer: I have full-color vision, but with color blindness there are (roughly) two dimensions of color, whereas most people have three (and a black and white photograph has one). What this means is that with 1D color, you can sort all of the colors you see into a line — dark to light. With 2D color, you can sort all of the colors you see on a flat plane. With 3D color, you require stacking colors.

Now, there’s plenty of animals out there that have more than 3 dimensional color (they have more than 3 types of cone cells). So two colors that look the same for a normal person will look completely different for an animal. Some octopi have eleven dimensions of color! To them almost every human would be severely colorblind.

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It’s thought that some people might be tetrachromats. They have 4 types of cone cells because of a genetic mutation. There’s still some questions on how this extra information is processed by the brain, but there’s a chance that for these people almost everyone else seems colorblind. They are able to distinguish two colors that everyone else cannot. This also means that television won’t reproduce colors correctly for them, and it won’t look natural.

— Xcelerate 1 day ago

— Hacker News

2012.08.04 Saturday ACHK