A clapper loader, or second assistant camera (2nd AC) is part of a film crew, whose main functions are that of loading the raw film stock into camera magazines, operating the clapperboard (slate) at the beginning of each take, marking the actors as necessary, and maintaining all records and paperwork for the camera department. The name "clapper loader" tends to be used in the United Kingdom and Commonwealth, while "second assistant camera" tends to be favoured in the United States, but the job is essentially the same whichever title is used. The specific responsibilities and division of labor within the department will almost always vary depending on the circumstances of the shoot.
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