A perceptual illusion I hadn't seen before

[mmcirvin]

Mr. Angry and Mrs. Calm. Which is which? How far away are you standing?

And how'd they do it? Mr. Rowland doesn't understand how it works, but I think I do: from close-up, your eye and brain's feature detectors are mostly registering high-frequency information in the picture; from far away you can't see that at all so you use the low frequencies instead. So you can make an ambiguous image like this just by superimposing images made with different Photoshop filters.

The page it came from has another one with Margaret Thatcher and Tony Blair, in which they pull a trick with the background to make it work better (to compensate for Thatcher's bigger hair).

Comments

[mezdeathhead.livejournal.com]

That's crazy.

[tomscud.livejournal.com]

Wow, that's pretty cool. I looked at it at first pushing between one and four feet from the screen, and it didn't work at all, but when I walked across the room, it was totally there. I was half-expecting it to be like those random-dot stereogram things, which I cannot see at all, ever. Probably on account of the secret mutant element in my makeup that makes me different.

[mmcirvin.livejournal.com]

I can't see those things either, but it's no surprise in my case since I have a somewhat lazy eye (had surgery for it as a kid) and my stereo vision has never been the best.

[paracelsvs.livejournal.com]

I am somewhat unconvinced by people saying they "can't see" random-dot stereograms as if it was some sort of medical condition. I can see them, but it takes effort, and often a bit of non-obvious trickery.

So I can't shake the feeling that people who say they can't see them only mean that they tried, and gave up before they figured it out.

[iayork.livejournal.com]

I've never seen one. I give up easily, though, because I can't imagine what possble benefit it is to me to stare at these things for a half-hour, in order to see a vague and fuzzy picture of something I'm not interested in. If the whole point is that illusions R kewl, well, that's a concept I've been fine with since I was four, and I don't need to reinforce it any more.

[doctroid.livejournal.com]

There are stereograms meant to be viewed crosseyed, and stereograms meant to be viewed walleyed.

I can see the crosseyed ones, but have never succeeded in viewing the walleyed ones.

[mmcirvin.livejournal.com]

Actually, I'm pretty sure I just can't. These things grew out of the experiments of Béla Julesz with very simple random-dot stereograms, and those original stereograms, in which the shape is just something like a square, I can see. The problem with the "Magic Eye"-type ones is that, while I can fuse the images and see a vague sensation of something with depth, that's all I can see-- I simply can't extract complex shape information from my stereoscopic depth perception alone, especially when the dot pattern is itself something complex. I assume that this is the result of my brain adapting to years of frequent double vision and only intermittent image fusion.

Stereogram

[3dimka.livejournal.com]

Have you tried a stereogram with proper texture? Like this one:


(http://skill.ru/users/3dimka/gallery/stereograms)
There is no hidden image in it, but the camel becomes 3Dimensional ;)

Re: Stereogram

[tiredintexas.livejournal.com]

A part of me dies every time I'm encountered by one of these things. I CANNOT see them.

I've wasted HOURS trying to see these things. And I'm not color blind (I've heard color blind people can't do these). I have 20/20 vision.

I've tried using double vision, crossing my eyes, getting close and slowly moving away (which does the same for me as double vision), and even looking in front of the image (just before my eyes would become crossed).

I've tried the "easy" ones as well as the "difficult" ones.

Nothing.

Re: Stereogram

[3dimka.livejournal.com]

You need not to cross your eyes, but you should look through the stereogram. The 3D image will appear beyong the screen. Color blindness doesn't affect 3D vision, but big difference between left/right eye visibility does affect.

However, there's crossviewing version for some stereograms, where you should to cross eyes slightly. Try this one for your cross viewing:


3Dimka (http://skill.ru/artwork/88212.shtml)

Re: Stereogram

[tiredintexas.livejournal.com]

I can't see the cross-eyed ones.

I get to the point where I can make out some depth, but I can't "focus" on any specific figure.

If I'm lucky and view it the other way I can see the figure...but it's inverted.

cross-view version

[3dimka.livejournal.com]

If you can't focus try to move the picture further from you. And give some more time for your eyes to adjust. It's unnatural for them to focus on the object you look through, however it is a good exercise for them.
Also you may try reading glasses if you have one.

This one is inverted because it's for cross-viewing

There's a new 3D stereogram group at yahoo you may want to join:
http://groups.yahoo.com/group/3D-Stereograms/

[ronebofh.livejournal.com]

I've seen one stereogram, and i hurt a lot after that. It's unnatural.

[jmkelly.livejournal.com]

I think your explanation is on the right track. There are two different sets of "anger" signals: in the portrait on the left, they're narrowed eyes, wrinkles around nose and bared teeth, which all disappear as you move away. In the portrait on the right, the highlighting of the area around the eyes, the lips, and (I think) the chin produces the illusion, when viewed from a distance, of widened eyes, bared teeth, and jutting chin.

[mmcirvin.livejournal.com]

Right. I realized after I wrote that that the use of "high-frequency" and "low-frequency" was probably what people found incomprehensible, so another way to put it is that one picture has a blurry angry face with fine details from a calm face, and the other has a blurry calm face with fine details from an angry face. When you can see the fine details, they dominate your perception of what the face looks like; stand back and they drop away.

I suspect I didn't have to stand back as far as tomscud because I am myopic, but not myopic enough that I have to wear my glasses at the computer, and I wasn't wearing them.

Pentomino?

[vardissakheli.livejournal.com]

Does this work at all on someone who's straining just to see them at all? Or do you just get a mishmash of both sets of features?

I think what makes this particular pair work so neatly is that some features of each face (e.g., angry eyebrows, calm eyes, angry lower lip) overlap the other face in such a way that they look like natural highlights or shadows.

Being Nearsighted has the same effect

[stevendaryl.livejournal.com]

I've found that if I take off my glasses, I get the same effect as if I get farther away. Maybe that's obvious...