How do Magic Eye images work?

[CalMeacham]

It’s a trick. One out of four Magic Eye pictures is packed with a sheet of paper saying “Shh! You have been selected as one of our Team Assistants. Do not tell this to anyone. Here is the picture you will claim to see.” (and there follows a small B&W picture of a doggie or whatever they can use to fake it) “Think of the fun you will have tricking people. The best part is when they claim they can see a picture that isn’t there!”

Seriously, though, when they first came out I could make out the pictures if I tried really, really hard. It was difficult, but it is pretty cool to have a ghostly image seem to materialize out of nothing.

Damn! We’ve been found out! Sterilize!

Truthfully – when the Magic Eye craze started, many years ago, some evil company put out an apparent “Magic Eye” poster that actually wasn’t – there was no 3D picture. The whole point of the poster was to drive 3D enthusiasts insane.

[Chronos]

Screw that, just cross your eyes and you will see it.

I see comments like this often in discussions of these images, and they always puzzle me. I can parallelize my eyes fairly easily (or even diverge them a bit), but I have great difficulty in crossing my eyes without focusing on an actual close object (like the tip of my own nose), and it gives me a headache.

I guess people vary on this score.

[Ludovic]

I sometimes come across this when looking at historical cemetaries or other places where you are separated from objects of interest on the ground with cast iron railings. When I move, the railing appears to be at the same distance as the objects I was looking at!:eek: (Each bar merges with its neighbor when the stereo is resolved.)

[MessyPaint]

@Larry Mudd

It’s just supposed to look like a 3D craggy/cavernous thing, so don’t waste brain cells trying to figure out what it is.

I thought it was a Christmas tree. Still though, that is really impressive. I won’t dare ask how you go about making them in photoshop.

[OtakuLoki]

@yabob

2 - I get eyestrain and a slightly nauseated feeling if I do it for very long.

I seemed to be able to see them the right way, but I still got acute vertigo and the beginnings of a headache, and it took about 5 minutes to get the image. Once I had convinced myself there were images there - I stopped looking at them, the pleasure wasn’t worth the pain.

[Hampshire]

If you want an ultra-basic example of how it works do this:

Touch your two index fingers together and what do you see, two fingers touching eachother.
Now hold them in front of your face about 6 inches away from your eyes. Now look past them out a window or something. Now what do you see? Two fingers holding a third double ended finger.
That’s similar to how they work. The images merge together one you focus at a point past them.

[ryobserver]

A lot of people can’t see anything in Magic Eye pictures, and a small percentage of the population never will. It takes practice, it requires good teamwork from your two eyeballs, and it won’t happen if you have certain vision problems. Info and tips from author of a Magic Eye book here, for those really interested.

[pool]

As noted above (in more than one place), with most such images, which you will see something, it won’t be the intended image. It will be an “inside out” (pseudoscopic, actually) image, that might actually be harder to correctly interpret. The “Look Through” method is, in most cases, what you need to see it properly.

So are you saying you will not see the image at all if you cross your eyes, or that it will be a distortion of what you are actually supposed to see or what? I’ve had a magic eye book before and when I crossed my eyes, the image I saw matched what the part in the back of the book where they reveal them. It doesn’t seem especialy hard to correctly interpret the image.

[Baine]

I can control the focus of my eyes pretty easily, so I can see the magic eye posters without any trouble. I’ve found that this technique can also be used on those picture games for kids where you have to spot the differences between two nearly identical pictures. I just merge the two pictures and the differences become apparent.

[Larry_Mudd]

@pool

So are you saying you will not see the image at all if you cross your eyes, or that it will be a distortion of what you are actually supposed to see or what?

If you cross your eyes instead of going “wall-eyed” (focusing on a point beyond the page) then your left eye is seeing the image intended for your right eye and vice-versa. You can see the image, but the depth will be reversed.

The way parallax depth perception works, the closer something is, the further left it appears through your right eye (compared with its apparent position in your left eye.)

If you look at (most) single-image stereograms cross-eyed, you’ll get the reverse of the intended effect – so close-up pixels will appear further away, and far-away ones will appear close, convex becomes concave, etc. You can still see the outline of the object, of course – enough to figure out what it is, but it won’t appear correctly, and complicated images will be harder, because of the conflict between perspective cues and parallax cues.

[pool]

Oh my god you’re right I just looked at this image that was supposed to be a dinosaur and the image I saw when I crossed my eyes was totally weird, but then its like the image suddenly changed and made sense, and I realized I wasn’t crossing my eyes any more. :smack:

[Baffle]

I haven’t been able to ever see these.

… before today. Thanks for the thread, now I finally know what all the fuss is about. Kind of disappointing actually.

And yeah, I can only do it crosseyed, the shark in the wikipedia article is indented. It would probably be cooler if it bulged outward.

[DWMarch]

@Baffle

I haven’t been able to ever see these.

… before today. Thanks for the thread, now I finally know what all the fuss is about. Kind of disappointing actually.

And yeah, I can only do it crosseyed, the shark in the wikipedia article is indented. It would probably be cooler if it bulged outward.

I’m in the same category although I think the ability to finally see these images is endlessly cool! No more standing around with a frustrated look on my face while everyone else goes by telling me it’s a sailboat!

[SentientMeat]

I’m afraid you probably won’t be able to see these ever, Revenant. The stereoptic processing required “comes online” in the visual cortex when one is only a few weeks old, and if the inputs aren’t there then true stereopsis is sadly lost when “unused” neural connections are “pruned” later in development.

This is actually why infants born with a ‘lazy’ eye have corrective surgery very early in life compared to later in childhood as it used to be. If your lazy eye or other optical defect is corrected too late, you no longer have the “hardware” to process those inputs anyway.

[uglybeech]

I could never see the things, but then had to learn to look at molecular stereograms in biochemistry, and after that I had no problem seeing Magic Eye images.

Here are a few of that type of stereogram that I found on the web if anybody wants to try the method that worked for me - the idea is to bring the two images together by going crosseyed, so that you get a three-dimensional image in the middle.

simple cube
man and baby
some kind of fractal
glucagon
part of the moon
benzil

After you can see these in 3-d go back and try the magic eye images. I bet you’ll find it’s much easier to do.

[Malacandra]

Ack! Cannot find the range on that fractal thing - the others resolved with more or less ease. It was really hard to find the depth with that man and baby picture, but it and the others were all viewable by the “parallel look” Magic Eye technique. Liked the rotating glucagon!

[CalMeacham]

Quote:
As noted above (in more than one place), with most such images, which you will see something, it won’t be the intended image. It will be an “inside out” (pseudoscopic, actually) image, that might actually be harder to correctly interpret. The “Look Through” method is, in most cases, what you need to see it properly.

So are you saying you will not see the image at all if you cross your eyes, or that it will be a distortion of what you are actually supposed to see or what? I’ve had a magic eye book before and when I crossed my eyes, the image I saw matched what the part in the back of the book where they reveal them. It doesn’t seem especialy hard to correctly interpret the image.

As I plainly say in the bit you quote, "you will see something[but] it won’t be the intended image. “It will be an ‘inside out’…image”. How could I possibly make it plainer? There are some cases where the image is intended to be seen cross-eyed (see my earlier posts, farther above), but almost all “Magic Eye” images are intended tyo be “looked through”. If you’re seeing them not inside out, then I suggest you’re ot really looking at them with crossed eyes.