Wheels Must
When cars drive forward, why do the wheels look like they are spinning backwards?
When I look at a car, the wheels spin forward.
When I look at a car on tv, the wheels "spin" backwards.
Must be the film or the camera doing this.
Any one know what is going on?
it depends on the camera setting. on normal exposure (no shutter), quick movement is just a blur. but if the high speed shutter is on then you can get the effect because the shutter eliminates the blur and take a sharp picture. so suppose the wheel comes just short of making a full turn then the shutter goes, then in the next frame advance it almost but not quite makes another turn. so the ratio of wheel spin to frame rate is critical, in some cases the wheels may turn slowly ahead, in other times they appear to spin back. in the 60s and 70s you saw this in the movies a lot because their cameras had to shutter to control exposure. but it was not untill the invention of the CCD in about 1984 that television/video cameras had shutters.
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