3 ms·

I have normal stereo vision, but I remember struggling for many hours to see random dot autostereograms (e.g. Magic Eye images). And then suddenly I saw the 3D

by mrob 7y ago

I have normal stereo vision, but I remember struggling for many hours to see random dot autostereograms (e.g. Magic Eye images). And then suddenly I saw the 3D image, and after that I never had trouble seeing them again. I've heard many anecdotes of similar experiences. Maybe there's a similar kind of learning in this case.

janci 7y ago
I have never come to see anything in these dots. I tried multiple times using various viewing tutorials and failed every time. I hope this does not work the other way - you see stereo, look at a stereogram you are unable to view correctly and boom - you're stereoblind.
munificent 7y ago
A large part of the struggle you experience with these is that you force your eye to do two clashing operations that usually proceed in sync. Among the signals our eyes use to detect depth are: * Accommodation: Our lenses are flexible. We unconsciously contract the ciliary muscles in our eyes to change the shape of the lens so that it focuses light at different distances. It's very similar to adjusting the focus ring on a camera or binoculars. * Convergence: As an object moves closer to you, in order for the object to stay centered on the fovea of each eye, your eyes need to turn inwards. To look at something really close, you go cross-eyed. When looking at something far away, your eyes are parallel. Both of those involve muscular control that also give feedback to your brain. So you can unconsciously feel how much your lenses are accommodating and your eyeballs are converging. Typically, those signals are in sync with each other. Autostereograms break that. To get the effect, you need to look "through" the picture. When you do, each eye isn't actually centering the same part of the picture on its fovea. That way, each eye gets a slightly different image, and the differences between those two cause a parallax effect that we perceive as depth. The problem is that as far as accommodation is concerned, the picture is close. The lenses really do need to focus on the picture itself to resolve a sharp image. But for convergence, your eyes need to be closer to parallel as if you were training your eyes on something past the picture. Now your brain can tell these two things are out of sync and it gets very confused. Some people seem to have an easier time decoupling these things than others do. It ends up a feeling a little like patting your head and rubbing your stomach at the same time.

by mrob 7y ago

janci 7y ago

I have never come to see anything in these dots. I tried multiple times using various viewing tutorials and failed every time. I hope this does not work the other way - you see stereo, look at a stereogram you are unable to view correctly and boom - you're stereoblind.

munificent 7y ago

A large part of the struggle you experience with these is that you force your eye to do two clashing operations that usually proceed in sync. Among the signals our eyes use to detect depth are: * Accommodation: Our lenses are flexible. We unconsciously contract the ciliary muscles in our eyes to change the shape of the lens so that it focuses light at different distances. It's very similar to adjusting the focus ring on a camera or binoculars. * Convergence: As an object moves closer to you, in order for the object to stay centered on the fovea of each eye, your eyes need to turn inwards. To look at something really close, you go cross-eyed. When looking at something far away, your eyes are parallel. Both of those involve muscular control that also give feedback to your brain. So you can unconsciously feel how much your lenses are accommodating and your eyeballs are converging. Typically, those signals are in sync with each other. Autostereograms break that. To get the effect, you need to look "through" the picture. When you do, each eye isn't actually centering the same part of the picture on its fovea. That way, each eye gets a slightly different image, and the differences between those two cause a parallax effect that we perceive as depth. The problem is that as far as accommodation is concerned, the picture is close. The lenses really do need to focus on the picture itself to resolve a sharp image. But for convergence, your eyes need to be closer to parallel as if you were training your eyes on something past the picture. Now your brain can tell these two things are out of sync and it gets very confused. Some people seem to have an easier time decoupling these things than others do. It ends up a feeling a little like patting your head and rubbing your stomach at the same time.