For what it's worth, a former film professor at BU told me a story once about how he had found it difficult to impossible to get permission to use actual film frames to illustrate a more-or-less scholarly book. He said that the movie studios want everyone to use "production stills" instead, which are high-quality conventional still photographs taken more or less concurrently with the actual production. I'm not sure exactly why they want this, but apparently most photographs "from films" that appear in traditional print media are production stills rather than actual frames. In his case, it was very annoying because he wanted to point out some lighting and compositional details which were quite different in the production stills and the actual film. He eventually shrugged his shoulders and decided to risk using the frame grabs without permission. This was a while ago and he never received any lawyer letters about it. His belief system--and I regard him as knowledgeable about this--was that _nobody really knows_ the the legal situation in such matters, absent an actual lawsuit. He held the conspiracy theory that intellectual properly laws are deliberately vague and ambiguous, because that insures power remains in the hands of companies big enough to retain lawyers.