Has anyone noticed

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navycop

navycop

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On the scion commercial (think it is the sti) the cars' hubcaps seem to be moving couterclockwise while the car is going forward? I tried to find a video on it. It's the commercial where the car is going across a bridge. They just show the car from the outside. Maybe they are those ones they call "spinners". I don't know.
 
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What you are seeing is a phenomenon called retrograde motion. You usually find it associated with planetary bodies but the same principle applies here, too.
 
It is the effect caused by the position of the object when the shutter operates. The object in in one position for the first frame, moves forward but the one behind moves into position slightly behind the first one for the next frame and so on and so on. this was very noticeable in many of the old westerns where the stagecoach was racing from the crooks. The wheels showed to be turning backwards while the coach moved forward. Just a photographic illusion.
Charles
 
You're watching your TV backwards. Just spin it around 180 and the wheels will be going the right way. Better yet, if you have a DVR, just put it in reverse.
 
No, it's a common thing...in all car commercials, I think, the wheels go backwards.

SOmething to do with the frame rate of cameras. Camcorders don't really take a smooth picture- they take a series of pictures and put them together in a way that hte mind doesn't notice.

Those sequential pictures, however, are slower or faster than the wheels' movement, so the wheel appears to move backwards.

Andrew
 
Its because of the cammera, saw that comercial while we were in Michigan. I got a kick out of the fact that the sleds I have been looking at are only 25 ponnies shy of that sports cars total horsepower.
 
This has been observed since the beginning of "moving pictures". If the frame rate of the camera is exactly the same as the rotation rate of the wheel, the wheel will appear to be motionless. It can also happen if it divides evenly into the number of spokes. If the frame rate is a little faster, the wheel will appear to spin backwards. If a little slower, the wheel will appear to spin backwards.

It's called the "Wagon Wheel Effect", in this wiki article:

http://en.wikipedia.org/wiki/Wagon-wheel_effect
 
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