So I just got around to playing with my custom function settings, and I was wondering, in a case of taking club photography (for my friend who DJ's) are any of these helpful? Long exposure noise reduction AF-assist beam -- it gets dark in the club I take photos in... should I leave it on Does not emit, Emits, Only emits ext. flash? E-TTL II - Evaluative or Average? Shutter curtain sync - 1st or 2nd?