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“Pigeon Neck” Illusion (2014)

michaelbach.de

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Re: “Pigeon Neck” Illusion (2014)

#41

Post by TheSpiceIsLife »

thomassmith65 wrote: post #12
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?

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.

How is viewing an image on a screen an illusion?

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

Re: “Pigeon Neck” Illusion (2014)

#43

Post by Daub »

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.

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

Re: “Pigeon Neck” Illusion (2014)

#44

Post by the_af »

jameshart wrote: post #16
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?

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 intere…

> 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.

Re: “Pigeon Neck” Illusion (2014)

#45

Post by meitham »

jareklupinski wrote: post #34
soxocx wrote: post #19

Earlier quoted context omitted.

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

I... only see it happening with either both eyes or my right eye... My left eye is immune? This is uncanny...

I’m the opposite! My right eye alone can’t see it, but can do with both or left only!

Re: “Pigeon Neck” Illusion (2014)

#46

Post by bmitc »

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.

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?

Re: “Pigeon Neck” Illusion (2014)

#48

Post by maegul »

the_af wrote: post #44
jameshart wrote: post #16

Earlier quoted context omitted.

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 intere…

> 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.

For me, just with the color slider, there was nearly always some sort of illusory motion. Transparent perception of the actual motion of the pigeons was either impossible or required precise conditions, which really affirms the power of this effect.

Re: “Pigeon Neck” Illusion (2014)

#49

Post by cornstalks »

xwdv wrote: post #27
eyelidlessness wrote: post #21

Earlier quoted context omitted.

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, pe…

Why do you think it takes more time and brain power to see the rectangles and pigeons correctly (smooth movement)? It was instantaneous and natural for me. I’m not convinced by your logic. It doesn’t seem like a disadvantage for a brain to naturally register the image correctly rather than being fooled by an illusion, especially when it takes zero effort.

Re: “Pigeon Neck” Illusion (2014)

#50

Post by aidenn0 »

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.

The color stepping feet version[1] I think definitely qualifies. The color contrast is high enough that if you focus on the leading or trailing edge of the "feet" it's trivial to see its moving the whole time, but if you look at the entire thing as a whole, the "stepping" effect appears.

1: https://michaelbach.de/ot/mot-feetLin/index.html

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