Editing Stroboscopic effect (section)

==Wagon-wheel effect==
{{main|Wagon-wheel effect}}
[[File:Propeller strobe.ogv|thumb|Propeller of a Bombardier Q400 taken with a digital camera showing the stroboscopic effect]]
Motion-picture cameras conventionally film at 24 frames per second. Although the wheels of a vehicle are not likely to be turning at 24&nbsp;revolutions per second (as that would be extremely fast), suppose each wheel has 12 spokes and rotates at only two revolutions per second. Filmed at 24&nbsp;frames per second, the spokes in each frame will appear in exactly the same position. Hence, the wheel will be perceived to be stationary. In fact, each photographically captured spoke in any one position will be a different actual spoke in each successive frame, but since the spokes are close to identical in shape and color, no difference will be perceived. Thus, as long as the number of times the wheel rotates per second is a factor of 24 and 12, the wheel will appear to be stationary.

If the wheel rotates a little more slowly than two revolutions per second, the position of the spokes is seen to fall a little further behind in each successive frame and therefore, the wheel will seem to be turning backwards.