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).
> 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.
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.
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.
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.
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.
(I think people like to call this “steel man” or whatever but just generally applying a charitable interpretation…) I think their take on optimization is about falsehoods about reality that our brains assimilate to make functioning or survival possible under certain circumstances, like perceiving magenta as not-green or being able to observe a field of grass without being hyper aware of each blade of grass within it.
All of which is good insofar as it actually serves us, but it’s really weird to me to frame it so absolutely. It’s not an optimization if it doesn’t serve us and we’re just misperceiving reality for no purpose, and there’s nothing wrong with you or anyone else who doesn’t. If anything it’s just… “wow, electrified meat evolved to be conscious is really wacky and super subjective!”
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.
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.