A perceptual illusion I hadn't seen before

[mmcirvin]

Mr. Angry and Mrs. Calm. Which is which? How far away are you standing?

And how'd they do it? Mr. Rowland doesn't understand how it works, but I think I do: from close-up, your eye and brain's feature detectors are mostly registering high-frequency information in the picture; from far away you can't see that at all so you use the low frequencies instead. So you can make an ambiguous image like this just by superimposing images made with different Photoshop filters.

The page it came from has another one with Margaret Thatcher and Tony Blair, in which they pull a trick with the background to make it work better (to compensate for Thatcher's bigger hair).

Comments

Re: Stereogram

[tiredintexas.livejournal.com]

I can't see the cross-eyed ones.

I get to the point where I can make out some depth, but I can't "focus" on any specific figure.

If I'm lucky and view it the other way I can see the figure...but it's inverted.

cross-view version

[3dimka.livejournal.com]

If you can't focus try to move the picture further from you. And give some more time for your eyes to adjust. It's unnatural for them to focus on the object you look through, however it is a good exercise for them.
Also you may try reading glasses if you have one.

This one is inverted because it's for cross-viewing

There's a new 3D stereogram group at yahoo you may want to join:
http://groups.yahoo.com/group/3D-Stereograms/