Before the invention of sound, films were shot at 18fps (rather than 24fps today). The frame rate was increased to 24 because 18fps was too slow for decent sound recordings.

Silent films look sped up because they are shot at 18fps, but played back at 24fps. If you played them back at 18fps, they would look normal.

Ben C.

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I heard it was 16fps but anyway.
Also it wasent so much the motion that was the problem but the flicker, on a computer screen if you watched something at 16fps it would look fine, the motion would be smooth (povided no one was moving too fast) this is because computers have a very fast screen refrest rate. On a traditional two bladed projector however picture looks flickery as so much time is being spent between frames. With a three bladed shutter however this can be avoided.
My advice is just shoot it at 24/25fps and treat is as a silent film, its not the fps that makes it a silent picture but the lack of dialouge or sound effects (and the outrageous melodrama for that matter).

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