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Just trying to understand, would it be correct to say that the Scifi site is a subset of the movies site on stackexchange? Would an in-topic question asked on both sites earn the same kind of answers? If so, why are there two sites?
It is difficult to know which is a suitable place to get answers for a particular question related to a Science Fiction / Fantasy movie, how does one choose where to post the question given cross posting is not an option?