If possible I'd recommenced that you record the mic audio separately and at the start or end of each recording, just record a bit of silence. This will give you a small sample of any constant background noise/static.
You can then use an audio program (I use audacity) to remove that section of background noise from the rest of the video.
If you want instructions for step by step (these would be for audacity):
For other programs, use Google.
- Highlight the small section of 'silent' audio you recorded at the beginning or end.
- At the menus along the top, go to Effect -> Noise Removal and click Get Profile. This will Adjust settings automatically for the actual noise removal.
- Use Ctrl + A to select all the audio and again, go to Effect and again, Noise Removal but now you click Remove Noise.
After that, you just merge the mic audio back into the video audio with an editor.
If recording the mic audio separately is not possible/you don't want to have to re-sync the audio together (really it's not that hard), you could also record it all together but any sounds from the actual recorded video audio would have to be stopped to record a good section for the noise removal from the mic.Edited by GAZ_MAN_432 - 8/14/13 at 6:29am