How to manage ambient noise during digital video production?

Ambient noise is the general noise that we don’t usually think much about because it surrounds us constantly. Ambient noise might come from chirping birds, an airplane flying overhead, chattering bystanders, passing cars, a blowing furnace, the little fans spinning inside your computer, and even the tiny motor turning the tape reels in your camcorder or tape recorder. Although it’s easy to tune out these noises when you’re immersed in them, they’ll turn up loud and ugly in your audio recordings later on. If you’re recording outdoors or in a public gathering place, you probably can’t do much to eliminate the actual sources of ambient noise. But wherever you are recording, you can take some basic steps to manage ambient noise:

• Use a microphone: I know, this is about the millionth time I’ve said it, but a microphone placed close to your subject will go a long way towards ensuring that the sound you actually want to record is not totally overwhelmed by ambient noise.
• Wear headphones: Camcorders and tape recorders almost always have headphone jacks. If you plug headphones into the headphone jack you can listen to the audio that is actually being recorded, and possibly detect potential problems.
• Shield the camcorder’s mic from wind: A gentle breeze may seem almost silent to your ear, but the camcorder’s microphone may pick it up as a loud roar that overwhelms all other sound. If nothing else, you can position your hand to block wind from blowing directly across the screen on the front of your camcorder’s mic.
• Try to minimize sound reflection: Audio waves reflect off any hard surface, which can cause echoing in a recording. Hanging blankets on walls and other hard surfaces will significantly reduce reflection.
• Turn off fans, heaters, and air conditioners: Air rushing through vents creates a surprising amount of unwanted ambient noise. If possible, temporarily turn off your furnace, air conditioner, or fans while you record your audio.
• Turn off cell phones and pagers: You know how annoying it is when someone’s cell phone rings while you’re trying to watch a movie; just imagine how bothersome it is when you’re making a movie! Make sure that you and everyone else on the set turns those things off. Even the sound of a vibrating pager might be picked up by your microphones.
  
• Shut down your computer: Obviously this is impossible if you are recording using a microphone that is connected to your computer, but computers do tend to make a lot of noise, so shut them down if you can.
  
• Warn everyone else to be quiet: If anyone else is in the building or general area, ask them to be quiet while you are recording audio. Noises from the next room may be muffled, but they still contribute to ambient noise. Likewise, you may want to wait until your neighbor is done mowing his lawn before recording your audio.
• Record and preview some audio: Record a little bit of audio, and then play it back. This might help you identify ambient noise or other audio problems.