It really depends on the nature of the shot. Is the person moving? Is the camera moving? Are things behind them moving? How far in the background are they? What's behind them? Does anything cross in front of them?
The basic principle of object removal, be it a person or a stunt wire, is to have an image of what would be there if they weren't there and put it over top of them (and their shadow).
The exact methods can vary wildly.
- The Great Szalam
(The 'Great' stands for 'Not So Great, in fact, Extremely Humble')
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