Cyberman (2001)
Cyberman is a 2001 documentary film about Steve Mann, inventor of the EyeTap. It was directed by Peter Lynch, but much of the material in the film was also shot by Mann himself, through his EyeTap. Thus Cyberman may well have been the first film in which the subject incidentally or existentially (i.e. just by being himself) shot much of the material used in the film.
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