its not our eyes but the brain and the frequency it needs to calculate what input it gets from the eyes.
if our brain would "see" faster we would be able to see bullets shot out of a gun.
because its damn slow we need special flare ammuniton for it

of course our vision bandwidth is limited but there is no separation into frames at a certain frequency or something like that. we see continuously and not like a camera.

also if our temporal resolution were limited to ~ 24fps we couldn't see the difference between film and video footage that easily and games wouldn't look better at 60fps but 24fps would suffice.

The point of my post, of course, was not about HOW it happens in real life, but that it CAN happen (contrary to what JCL stated).

I don´t think lifeforms see in pictures. If something moves very fast we see a blurred mix of endless sequences. Very simple example, if you watch out of the driving train you don´t see every third bush, you see a smeared green line. Or a rotating picture with black and white stripes gets, grey, acutally it doesnt gets grey it gets colorfull, but that´s still not a single picture, but a mix of endless pictures.

By the way, semimodern video games, have the choice to play them with 50Hz or 60Hz. And with 60Hz it looks indeed more realistic. My teacher always says 30 frames are enough for a prerendered movie, but I think that's is so wrong because we see the interpolated frames as well. The motion blur. I mean if something moves with 60 frames per second in on 1/6second from left outside of the screen to right outside of the screen we should recognize something hushing from left to right. With 30 frames the movement from left to right has interuptions and should be less visible. Yeah it´s moving the same fast, but with bigger interuptions the object should be more invisible.

It´s like watching somethign when a stroboskob is on isn´t as easy as without stroboskob.

from what i've heard, the frequency at which our brain interprets the image coming into our eyes is between 60 and 80 hertz. my old software design teacher told me this when i asked him for some help and he said "excuse me" and changed the settings up to 80 hertz and explained that otherwise the image was constantly flickering, from what he could see. a quick look at wikipedia doesn't seem to confirm this, but that's just what i heard.

julz

No, one reflection would not suffice for that. You need two periodic effects with slightly different frequencies. So the second one was likely a reflection from another wheel. Maybe it was the wheel of your own car that you have seen reflected in the truck's wheel. Or it was a reflection from a vibrating part of the truck.

I see this all the time actually. Seems once a car gets past 40mph the wheels seem to go backwards. I'm also very near sighted and wear contacts so this might have something to do with it.

of course there is no framerate for our visual organs (nobody said that). the fact that you see blurred hands if you move it fast enough infront of your eyes idicates the speed our brain needs to interprete the visual ("framerate" if you dont mind the word ).
i doubt this spinback effect can be seen in real life. because if the wheel turns fast enough it will start to look blurred instead of turning backwards.

the strobe effect jlc mentioned (same as the frames of a movie) is what "saves" the position of the wheel. if it fits the alias effect sheme then our brain will interprete it as backwards moving, still standing or forward motion.

in real life other optical illusion would be needed i think to achieve this effect (if possible)...something that "burns" or fakes single frames to our visual system as a tv would do (strobe lights maybe)

i also doubt it can be seen in real life (at least that easy) though i have never thought about it so far. I will have to take a look today when a car passes by

cheers