“Pigeon Neck” Illusion (2014)

https://michaelbach.de/ot/mot-pigeonNeck/index.html

by mnem • 3 years ago

344 78 3 years ago

michaelbach.de

xwdv2• 3 years ago

Jesus, this illusion is so powerful, you’d have to have a very poorly optimized brain to really see anything else.

sneak• 3 years ago

I can consciously toggle the illusion on or off.

mafuyu• 3 years ago

Yeah, this effect is pretty strong. After staring at it a bit, the only way I found to 'break' it was by noticing that if I flicked my eyes towards a bird, there was a brief period before the illusion kicked in. By constantly flicking my eyes between each bird, I was able to perceive them as moving linearly.

ancientworldnow• 3 years ago

They're just sliding smoothly for me unless I look at it without any focus as a disinterested viewer. I work on fixing moving pixels all day though so maybe I'm not an average subject.

cornstalks3• 3 years ago

It took me several minutes before I could see the illusion. I just saw grey rectangles and pigeons smoothly moving to the right and had no idea what the “illusion” was supposed to be.

glasss• 3 years ago

When I started messing with the color I ran into that. If I shifted to a different grey, it just looked smooth to me. But either extreme, black or white, and the illusion was there.

viraptor• 3 years ago

Now I wonder how much it depends on the gamma. I understand there's some differences depending on the hardware, browser and image format/metadata. By default we may all see a different shade of grey, affecting how much of an illusion we get.

Edit: checked Firefox and Chrome on Android and they look exactly the same (work on me). Low brightness works better than full brightness.

WarOnPrivacy• 3 years ago

It took me several minutes before I could see the illusion. I just saw grey rectangles and pigeons smoothly moving to the right and had no idea what the “illusion” was supposed to be.

Same here. After a bit I could see some worm stretching if I focused on particular points in the image.

I noticed that as soon as I registered all of the movement, my eyes fixed a certain way that they do when I'm driving and navigating an overly complex traffic situation. I was super reluctant to try to focus them any other way.

eyelidlessness2• 3 years ago

I see it, but it doesn’t feel optimal. What my brain is telling me I see is different from what I know is true about what’s on the screen. It seems to be interpolating between nearly and actually overlapping with each alternating stripe.

There are a lot of ways it’s optimal to be able to approximate and fill in details like this with normal visual processing, but literally not being able to unsee falsehoods (and I can’t switch it off in my brain like another commenter said they could) doesn’t feel like one of those optimal scenarios to me.

xwdv2• 3 years ago

A highly optimized brain doesn’t bother wasting time on getting fine details like this correct, it’s too slow and will lead you to getting killed in situations where a rough approximation of what you are seeing is good enough. People have to focus very hard to turn off the optimizations and see what is really going on, some can’t do it at all. Some people seem to be able to see the smooth linear motion by default, perhaps descendants of those who lived in simpler environments.

aoeusnth1• 3 years ago

Both me and my wife had to consciously blur our vision to see the illusion.

stefncb2• 3 years ago

If I look directly at a point, the illusion goes away there. And I don't really see anything strong anyway, so I wonder how you see it.

clhodapp• 3 years ago

Something I noticed and got a kick from: If you set the color to black or white then the real motion and the illusion are indistinguishable.

dawatchusay2• 3 years ago

I don’t feel this is much of an illusion. I think you just can’t see the movement of gray on black. Or maybe this is what illusions are in a very simple form?

TylerE• 3 years ago

Pretty much. Change the color to yellow and it’s very obvious.

yazzku3• 3 years ago

Yellow doesn't do it for me. But orange, oh boy.

anamexis• 3 years ago

How would you define what an optical/visual illusion is?

c3534l• 3 years ago

When your brain fudges the results of what you're seeing because of some hidden processing heuristic. If the bird were actually just colored black, then what we would see would be accurate. But its presented as if we should percieve continuous movement when we really shouldn't.

dawatchusay2• 3 years ago

I’m just saying upon initial thought that it seemed too simple to be considered an “illusion” because it doesn’t rely on some mental trickery, just blindness. But I’m willing to accept that optical illusions may all rely on some form of blindness. Glad to spawn the conversation!

thomassmith654• 3 years ago

Let's say you recreate this effect by painting the pigeons onto a transparency sheet, and moving the sheet above a paper with a striped background. The pigeon shapes would appear to bend, when in fact they do not... so in physical form, it clearly is an illusion.

As a pixelated image, I dunno: our insistence on viewing groups of pixels as shapes is an illusion to start with.

TheSpiceIsLife3• 3 years ago

How is viewing an image on a screen an illusion?

There really is an image there when viewed at the intended scale.

kuhewa• 3 years ago

With the pigeons it seemed illusory, but with just worms you can tell that's exactly whats happening. Dunno if it is the single-row shape or just less action on the screen allowing you to focus on one cell

jameshart• 3 years ago

Play with the color of the pigeons. Slide it all the way to black, and it's no longer an illusion - the edges really do move in steps. Slide it all the way to white and the same effect appears in the inverse.

Somewhere in between, there are shades of gray where the smooth movement of the pigeons is visible. And there are shades of gray where your brain can't separate it from the underlying black motion. That's interesting, no?

That's what makes all optical illusions interesting - exploring the thresholds where our brain's perceptual machinery takes shortcuts.

I've noticed there's a tendency, especially among smart people, to be dismissive of optical illusions. 'I didn't fall for it' - because to a certain personality, it's important to feel like your mind can understand things and you can't be 'fooled'.

But good optical illusions aren't fooling you. You don't need to feel defensive about whether you were 'tricked'. They're hacks that exploit edge cases in your visual cortex, and cause your brain to be fed erroneous data. They're interesting and useful because they help you calibrate the instruments your brain uses to collect data!

the_af• 3 years ago

Slide it all the way to black

For the record: the illusion still works for me if I slide the color all the way to black. One eye, both eyes, it always works for me.

justinpombrio2• 3 years ago

I'm confused what you think an illusion is?

tshaddox• 3 years ago

There is room for disagreement in some cases. “Look how the black text becomes invisible when it goes in front of a black background” is not what I would call an optical illusion, for instance.

IshKebab3• 3 years ago

Something that relies on unexpected or weird characteristics of the human visual system.

This just relies on poor contrast.

tomelders• 3 years ago

I feel like this is doing what an animator would do, just badly.

illegalmemory• 3 years ago

It would have been interesting to control the width of the vertical stripes too , to see at what point it "starts" being a illusion. I assume for very thin stripes it might not work so well .

d4mi3n4• 3 years ago

I was in bed reading this with an eye closed and was very confused until I discovered the illusion works for me only when I watch it with both eyes open.

I found this surprising—I know three dimensional optical illusions depend on focus and perspective, but I was unaware two dimensional optical illusions were as well.

soxocx2• 3 years ago

Thats interesting. I see it with either or both eyes.

PyWoody• 3 years ago

Try closing one eye and tilting your head 90°

jareklupinski• 3 years ago

I... only see it happening with either both eyes or my right eye...

My left eye is immune? This is uncanny...

bmitc• 3 years ago

The illusion is much less if I zoom in and even less if I close one eye, so maybe they had their device up close to their face?

stouset• 3 years ago

I let out a verbal "what the fuck" when I tried this. Same exact thing as you, it's absolutely striking.

d4mi3n4• 3 years ago

I was confused as well. First impression: nothing. Get up and look with both eyes and there it was. Interesting stuff.

aendruk• 3 years ago

Astigmatism? My eyes blur at different angles so various anisotropies show up only when one is closed.

d4mi3n4• 3 years ago

I do have an astigmatism in my right eye—which was also closed. First time I’ve had this happen with an optical illusion, though.

Daub• 3 years ago

As a one-eyes person, the illusion works fine for me. However, it ceases to work in the periphery of my vision.

stefncb2• 3 years ago

For me it weakens with one eye closed, but I still see it.

IshKebab3• 3 years ago

Worked a bit better for me with one eye closed. Weird.

tolmasky• 3 years ago

Hey, this is built with Cappuccino!

albert_e• 3 years ago

The illusion was very strong on my mobile screen and non-existent on my desktop screen. The screen calibration was different in the latter I believe so the pigeons were appearing as a slightly different colored grey blocks visually distinct from the vertical bars.

jrumbut• 3 years ago

Funny, I still get the illusion after turning the pigeons every color from dark grey to bright yellow.

Brighter colors make it a bit less strong but still very much there.

Enginerrrd• 3 years ago

On my laptop, I am only able to see the illusion if I looked at the striped background and blur my vision a little. Then it is quite impressive and strong. Otherwise, it always appears perfectly smooth for all colors.

daveslash• 3 years ago

I get the illusion for yellow, but not for bright red or blue. That's interesting....

aliqot• 3 years ago

I get what I'm supoosed to see but i dont see it, its pixels gliding continuously.

userbinator• 3 years ago

This seems to be, for lack of a better analogy, an effect of rounding colour intensities in the "motion compensation" processing of the brain. The grey and black become perceived as identical and thus no motion is detected in those areas where the two colours are overlapping.

sorokod• 3 years ago

I wonder what is the maximal extent of the craining and the shrinking illusion that can be achieved. Is it to do with the velocity? The grid thiknes?

If the illusion is an error, what maximizes it?

bella_sm• 3 years ago

DaVinci would have loved this!

newaccount74• 3 years ago

Here's my attempt at explaining this phenomenon:

Our Retinas don't send raw data to our brain like a camera sensor would. Instead, the neurons in the retina already do some pre-processing, like boundary detection, or movement detection. The brain then receives signals where movement was detected.

This movement detection is basically just detecting changes in light level, so it works better when the contrast is high (dark gray vs. white) and works less good when contrast is low (dark grey vs black).

So our brain gets stronger "movement" signals when there is high contrast, and it looks like the part that has high contrast is moving faster. Since the image is designed in a way that the boundary of head/body always have low/high contrast or vice versa, it seems they are moving with different speeds.

zestyping• 3 years ago

This isn't an illusion at all. Things that are too dark to see... are too dark to see.

Nothing to see here, move along.

“Pigeon Neck” Illusion (2014)

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