It's called retinal retention using complimentary colours.
The sky in the background is orange, and the colours in the base of the photo are cool colours corresponding to the warm colours as complimentary.
What happens is your eyes are drawing in your visuals and retaining the colours, and when the black and white photo appears suddenly they eyes automatically switch to the complimentary colours of what you've been staring at. In this case it turns to a blue sky (complimentary to orange) and green hues and brown hues (complimentary to the base colours) and you end up with the illusion of a coloured photograph until you remove the sight from your eyes. Blinking is enough do that.
lynnie
2008-02-29 03:54:57 UTC
When computers first came out (yes I'm that old), the screen was almost black and the letters were orange. After using the computer for a few hours, when you looked at the papers on the desk they had a "blue" shadow around them. I think it had something to do with your brain looking at the orange letters.
The explanation by the dog person sounds reasonable to me!!
jacquesh2001
2008-02-29 01:12:13 UTC
It's very amazing.
As to why, I don't know. Is the illusion that it is originally more or less B/W, or on the contrary that it gets its colours after a while ? (I'm speaking about the castle).
George T
2008-02-29 00:21:06 UTC
I don't see it changing colors... am I supposed to NOT blink??
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