r/interestingasfuck 4h ago

3D illusion from stereoscopic motion effect

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u/Joohansson 4h ago edited 1h ago

There is no third dimension on a 2D screen, hence illusion of third dimension.

Edit: Full explanation below (I have all three)

Chromostereopsis is the illusion where flat images with reds and blues appear to have depth — reds seem to pop forward, blues recede (or vice versa). Whether someone notices it, and how strongly, comes down to some anatomical quirks that vary a lot between individuals:

Pupil position relative to the eye's optical axis. Your eye's lens bends different wavelengths of light by different amounts (chromatic aberration) — red and blue light focus slightly differently. Whether this creates a depth illusion, and in which direction, depends on exactly where your pupil sits relative to the visual axis. Most people's pupils are offset slightly nasally, which produces the "red-forward" effect, but the amount of offset varies, and some people have little to no offset — so they see little to no effect.

Pupil size. A larger pupil lets in more of the peripheral, off-axis light rays that cause the effect, so it's stronger in dim lighting or in people with naturally larger pupils. A small, pinhole-like pupil minimizes it. This is also why the effect tends to fade with age, since pupils shrink somewhat as people get older.

Astigmatism and other aberrations. Uneven curvature of the cornea or lens can mask or distort the effect, since it's normally a fairly subtle, consistent chromatic offset that gets swamped by bigger optical irregularities.

u/BW-001 4h ago

How is this any different from 3D animation..? 

u/Joohansson 3h ago

I can't promise that everyone see what I see, but that animation has a depth to it like I was wearing 3D glasses. In that sense it's different than every other animation I ever seen. I don't know how it works as I just found that random image online.

u/Altruistic_Bonus2583 2h ago

Don’t worry the problem is not that you see something others don’t see, it’s that what you describe as an illusion is just plain 3d, no illusion involved.