Maybe not, but I sure wasn’t seeing them before they were invented. ;)[
I also remember as a kid the effect on the interior ceiling of the car, with chain lik fences etc. Stereo photography, of course, is at least 150 years old. http://www.usc.edu/schools/annenberg/asc/projects/comm544/library/images/466.html
Hmm, I’m also one of these people who can do both versions, instantly. I think once you “see” what you’re actually doing it becomes far easier. (The oft-explained techniques do nothing to reveal what you’re actually doing). I have a really cool stereogram wherein you “uncross” your eyes once and see one image, then you uncross your eyes a second step and see a second image!
Even when I was real young I was applying this “trick” to all sorts of repeated patterns - tiled wallpaper, chain link fences, etc.
Actually, it’s a UFO which happens to be the exact shape as a teapot. Or, if you will, a teapot in zero-gravity.
Some of these I can see almost immediately and others I NEVER see.
But this one is a teapot.
Chronos as I child I remeber doing something similar.
Point the forefinger of one hand, and the forefinger of the other, hold the fingers about 1cm apart.
Looking at the point between your fingers grudualy move the focus point furthar away from yourself.
BTW – I checked my bookcase, and I do have a commercial program to produce these. It’s called “Stereograms” by Jeffry S. Smith & Rick Kwiatkowski, subtitle: create your own stereograms.
It’s very old. Requirements: MSWindows 3.1 or higher, 4 megabytes RAM, 5 megabytes hard disk space, mouse, single speed CD-ROM or better.
I never did anything with it – I’ve got zip talent at things like this. I did stick it in the drive just now, and it booted and started up fine under WinXPhome.
Anyway, I’d be happy to send it (original disk, jewel box, & registration card – don’t see any point to sending the big empty box) to anyone interested enough to pay the postage.
Anybody?