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