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Comment by petercooper | Hacker News Reader

Also known as.. an animation! A 2D movie is not a "3D picture" merely by alternating two frames of it. You can get a sense of depth from any 2D sequence where the camera is moving. A more realistic approach is when you have two such frames side by side and you focus an eye on each.

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That's true, but this is a way to perceive depth for people who can't view stereoimages (e.g., people blind in one eye). You do experience some amount of depth even though each eye is receiving the same information.

From http://en.wikipedia.org/wiki/Stereoscopy#Wiggle_stereoscopy:

Wiggling works for the same reason that a translational pan (or tracking shot) in a movie provides good depth information: the visual cortex is able to infer distance information from motion parallax, the relative speed of the perceived motion of different objects on the screen. Many small animals bob their heads to create motion parallax (wiggling) so they can better estimate distance prior to jumping.

True, but with a strong emphasis on the word "some." If you wiggle a 1D line, you experience "some" sort of 2D. If you flicker a 3D scene back and forth a second, you experience "some" sort of time. But these things are woefully poor mirages that only seem impressive for a limited time.

No... Its not just animation. The alternating images tricks ur brain. BUT this gives me major headaches almost immediately.

While yes animation does sort-of give the perception of 3d, the images here really do appear to have depth in the monitor. Its a cool trick. Now I am guessing we need to play this at a rate of 30fps each image (thus 60fps) or so so that we don't "see" the non-3d image alternations but we experience it nevertheless without a headache I might add.

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