You want a good condenser (externally powered) mic with a ?lobar? pick up pattern to put on your boom pole. Lobar pick up means the mic focuses its audio pick up to a narrow area. This is why you want to use a boom pole to get the mic as close the the actor as possible - you?ll get clean dialogue tracks with less ambient noise.

There are three main suppliers of shotgun mics:

?url? http://www.sennheiserusa.com/newsite/?/url?
Sennheiser is the mic most used by professional sound recordists. They are expensive and worth it. Check out the ME-66 and the ME-67.

?url? http://www.audio-technica.com/?/url?
Audio-Technica makes great mic?s and they?re cheaper. Check out the AT835b.

?url? http://www.azdencorp.com/?/url?
I?ve never used Azden mic?s. They?re inexpensive but I?ve don?t hear too many good things about them.

A good mic is an investment. It will last longer than your camera - why skimp?

The further away the mic is from the actors, the higher the volume needs to be. The higher the volume, the more ?noise? you get. Your goal is to have a very high signal to noise ratio - more signal (the dialogue) less noise (the background). Even a very good, expensive Sennheiser mounted on the camera will pick up a lot of background ambiance because it?s far away from the actors.

So you need a boom pole. This can be as simple as a painters pole with a microphone shock mount on it - or a 3 or 4 section, expandable Carbon Fiber, Graphite Fiber or Aluminum boom pole. The lighter the pole the better. Expandable is also very convenient. A pole that?s a fixed six or eight feet (painters pole) can pose problems if you?re shooting in a small space like a bathroom or small apartment or if the boom operator needs to be twelve to fifteen feet away to be out the the lights.

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The aim of an argument or discussion should not be victory, but progress.
Joseph Joubert, essayist (1754-1824)