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“Pigeon Neck” Illusion (2014)

michaelbach.de

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Re: “Pigeon Neck” Illusion (2014)

#21

Post by eyelidlessness »

xwdv wrote: post #2

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

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.

Re: “Pigeon Neck” Illusion (2014)

#22

Post by tshaddox »

justinpombrio wrote: post #18
dawatchusay wrote: post #4

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?

I'm confused what you think an illusion is?

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.

Re: “Pigeon Neck” Illusion (2014)

#23

Post by PyWoody »

soxocx wrote: post #19
d4mi3n wrote: post #17

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.

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

Try closing one eye and tilting your head 90°

Re: “Pigeon Neck” Illusion (2014)

#25

Post by viraptor »

cornstalks wrote: post #13
xwdv wrote: post #2

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

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.

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.

Re: “Pigeon Neck” Illusion (2014)

#27

Post by xwdv »

eyelidlessness wrote: post #21
xwdv wrote: post #2

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

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 ca…

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.

Re: “Pigeon Neck” Illusion (2014)

#28

Post by justinpombrio »

tshaddox wrote: post #22
justinpombrio wrote: post #18

Earlier quoted context omitted.

I'm confused what you think an illusion is?

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.

I would describe an illusion as something where my (say) visual cortex is lying to me. This results in an image looking very odd: I _know_ that one thing is happening, but it looks like something else is happening.

Black text going in front of a black background doesn't have that effect. My knowledge of what I'm seeing agrees with what I see. My knowledge is "there is black text in front of that black text", and my visual cortex says "sure, I can't see it but that's perfectly plausible". This pigeon video does have that effect. My knowledge says that the pigeon image is moving smoothly, but I can clearly see its head bobbing; there's a disagreement.

Do other people define "illusion" differently? Or perceive something differently?

Re: “Pigeon Neck” Illusion (2014)

#29

Post by WarOnPrivacy »

cornstalks wrote: post #13
xwdv wrote: post #2

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

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.

> 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.

Re: “Pigeon Neck” Illusion (2014)

#30

Post by cornstalks »

viraptor wrote: post #25
cornstalks wrote: post #13

Earlier quoted context omitted.

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.

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.

That’s certainly a possible factor. I’m on an iPhone 14 Pro with brightness at medium levels in an averagely lit room using Safari. I just tried on my Mac’s XDR display and it’s similar: I can either see or not see the illusion (now that I know what the illusion looks like I can turn it on/off in my head).
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