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TIL I'm not the only person that sees slightly different hues with each eye (lemmy.world)

submitted 1 week ago by [email protected] to c/til

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If I close one eye for a few minutes and then switch which eye is closed I see a very (very) subtle difference in hue.

Left eye sees a green tint; right eye sees a pink tint. It's more obvious when I'm looking at a white wall on a bright day.

I don't get this effect if I don't let one of my eyes adapt to the dark first.

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[–] [email protected] 26 points 1 week ago

That’s because our eyes adapt themselves to different colour temperatures all the time during the day (a tungsten light bulb has very warm (orange) light, while daylight is much cooler (blue), for example, yet white is always white to us). This happens automatically and subconsciously.

If you close one eye for a little while though, it „resets“ back to its default colour temperature. After opening it again, it’ll take a little while for it to start compensating to the correct white point again and thus you‘ll have different hues on both eyes for a little while.

The effect is exaggerated a lot, if you close one eye and then look at a bright monochromatic image with the other one (like a bright red image on your phone, close to your face).

Or, of course, if you wear anaglyphic 3D glasses (that’s the red/green or red/cyan kind) for a while, as one eye will try to compensate for the red as much as it can, while the other one will try to compensate for the green/cyan as much as possible. Result: the eye with the red glass will look much cooler after taking off the glasses, and the eye with the green/cyan glass much warmer.

Generally that effect will balance itself out after a little while. Except for very slight variances of course. Our eyes and brains are far from perfect.