This is not an optical illusion but known as chromatic ocular adaptation or color adaptation of the eyes. In ocular physiology, adaptation is the ability of the eye to adjust to various levels of darkness and light.

     Your eyes are balancing the colors you see. The same thing happens if you've ever had orange ski goggles on for any length of time. Eventually, you see normal colors, and when you take them off, everything's blue! It's because your eyes have adapted to orange, so your brain compensates - when the orange goes away, your brain is still compensating for it. Same thing is happening here: you're forcing your brain to compensate for the color negative by adapting in the other direction, which also happens to be the correct colors of the picture when you take the colors away.

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