The only filter I ever really use on my camera would be a polarizer. shrug ....I have camera bag full of creative Cokin filters...never use them. Multiple exposures...no, but not for lack of trying, my Nikon has auto advance so I'm not sure I can do it, on my old Canon I tried but couldn't get it to work! :~( Bleech... At this point I do not have access to a wet darkroom...my darkroom is the digital one. I think all of the techniques you've mentioned to me are photographic art techniques. Not pure photography....these things can also be accomplished in the digital darkroom which is a great thing....LOL! I'm not that much of a purist... They're all tools...and I can only speak for myself and how I feel about it...it's all subjective. I am just not into heavy manipulation with PS filters.

I am, therefore I create.......
--- michelleamarante.com