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The physics of vision is amazing and confounding, IMO.
Like, the thing about 24 frames a second being enough to trick us into seeing smooth motion is only scratching the surface, but it is related to the lazy second hand on a clock phenomenon, too. Our eyes respond to light stimulus in a time-averaging manner, over very short time scales. It takes time for a photon to be absorbed by a rod or cone in the eye, and for that rod or cone to be reset into its ready state to receive another photon.
Kinda like turning on and off a switch. It takes a moment for that "signal received" state to be reset to a "waiting for signal" state.
And the brain has had to deal with this from birth. So it takes that switching time as if the signal is on during the whole time, and then assumes it will stay the same until the next signal comes in... which may not happen if it's pitch dark, but you'll see that after-image behind it, because your brain was expecting the same thing, then it wasn't there, so it time-averages the expectation with the actual.
There's time-averaging going on in the quantum mechanical process of absorbing a photon, then having that state reset. Then there's more time-averaging in the processing of that signal into an image in the brain.
Now there's the issue of motion-blur. I'm sure we've all seen what happens when a camera rapidly swings from one position to another. The image goes all blurry when the camera is rotating. Well... same thing happens to the image your eye sees when you swing your head around. However, your brain just filters all that out as "useless" information, and it filters it so well, that we're not even conscious of the fact that LOADS of the information coming in from our eyes is in this motion blur phase. The brain just totally ignores it. Having done so, there's this break in time in our visual perception. The brain "solves" that by retroactively stitching the image you see after the motion blur onto the time that was motion blurred.
So like, you swing your eyes from left to right, e.g. Your brain makes you "see" the image on the right from the moment you started to move your eyes, not the moment your eyes came to rest at the right.
When you look at a clock, and the second hand seems to hang there for too long, that's because the second hand had just ticked in the moment before you looked at it. Your brain filtered out the confusing motion-blur of swinging your eyes around, and then stitched back in time, the image it received when the motion blur stopped. Adding few hundred milliseconds to the image of the second hand standing still. That's a notable %-age of a second, and you notice that extra time, even though your brain lied to you about what you were actually seeing.
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