I don’t know if this is answerable, but it’s a question that has been randomly bugging me. When you look at, say, a 3-d movie with the red/green glasses, does it actually look as if it’s popping off the screen? If not, what makes it look 3-d?
Similarly, what do Magic Eye and similar images look like (the ones that look like just random static at first)? Popping out of the page? Are they in color?
(I have some weird eye…thing where I can’t see those, because my brain refuses to properly combine the images from both eyes or something. This was a source of endless frustration in elementary school.)
They look like they’re sticking out of the page, but the illusion is easily broken, because moving your head about doesn’t cause the parallax effects you’d get with a real solid object field.
The most convincing one I ever saw was an engraving of a housefly, blown up to about six inches long - it didn’t use red/green glasses - I think they were polarised, but when I put them on to look at it, it did look like a big model of a fly standing there on the frame - I reached out and tried to grasp the wings (I was four years old - this was at a visit to the optician).
It looks basically like a hologram. I assume you can see those. Magic-Eye picture take practice sometimes as much as a few hours. The skill comes from defocusing your eyes in a minor cross-eyed kind of way. They aren’t just something a person walks up to and can see right away. It took me a couple of days when I got a book of them. It is an acquired skill.
Stereograms look like a 3-D image floating in front of a screen. The image and the screen are composed of the same colors (pattern, actually) as what you see when you just look at the stereogram as if it were a piece of paper. To make it work, you just have to get your eyes to focus behind the image. It can be tricky to get it to work, but the funny thing is that once you do it, it’s hard to undo it.
The fly thing, I happen to know, is a common eye test to check stereoscopic depth perception. If your eyes put the two images together properly, pop goes the fly off the frame. If not, you finally learn to fib to the doc until you finally confess years later that you’ve faked ‘picking up the wings’ all along (or perhaps that’s just me).
Bah, so says everyone with normal vision. I had serious amblyopia as a kid and never was fully cured. I have been told by an optometrist that nope, you’re never going to be able to see the hidden shark/dolphin/lemur/whatever.
For some reason I always imagined that the actual image would somehow not have the random-dot pattern. Interesting.