Picture two prints side by side, neither of them look like much of anything alone but you notice that the first one has a tiny dot in the center.
You stare at it transfixed, wondering why the artist would have placed a tiny mark on such a relatively bold work. It seems completely out of place in the middle of such dark lines and bright colored splotches on an otherwise white background.
You have already glanced at the second print and were not overly impressed with the artist’s talent. It looked like something Polluck might have done in grade school, but now you are curious to see whether this one has the same incongruent dot in the centre so you have another look.
There is indeed a small dot on this one too.
As your eyes jump to it, the after image of the first print superimposes itself on the second and suddenly they both make sense.
Alone, neither seemed worthy of being hung in your guest bathroom, but now you see that they would not be so out of place in the bathroom...at the Louvre.
-- 2 fries shy of a happy meal, Jul 30 2003

Magic Eye http://www.vision3d.com/stereo.html
something similar? [stupop, Oct 04 2004, last modified Oct 21 2004]

Negative Afterimages http://www.explorat...bird_in_a_cage.html
These work better on a printout. [Amos Kito, Oct 04 2004, last modified Oct 21 2004]

You mean the viewer's brain superimposes the two images to form a single, complete one?
-- snarfyguy, Jul 30 2003


Exactly right. I had thought to combine the after image effect to make a color random dot stereogram, but I don't think that the image would linger long enough to see the iliusion.
-- 2 fries shy of a happy meal, Jul 30 2003


Here's a [link] demonstrating the phenomenon. The picture remains in the eye, but as a negative image (black is white, etc.).
-- Amos Kito, Jul 30 2003



random, halfbakery