To me, the "camcorder look" can really go a long way toward making a film look more like a document of what some people are doing than a movie.
Below is a trailer for August Underground. Obviously they have played with the audio/slow-mo for the trailer and they have upped the contrast/went black and white for the nudity part, but just this little bit really does make me feel like I'm watching real psychos videotape each other humiliating and slaughtering people. Dunno, just really find it disturbing.
What I'm trying to say, is that it feels more real to me than I think it would if they would have had a bigger budget. With a big budget, it makes it easier to distance yourself from the violence because you can tell "it's just a movie." That's why movies like Saw really don't disturb me.
But if real psychopaths were just documenting their sadism, this is what it would look like imo:
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I realize that "sickest/most violent" is kind of off topic for this thread, but we've discussed most of the movies in this list/clip:
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