All video cameras have a built-in microphone, but that doesn’t mean you should use it. Learn more: Media College’s Audio for Film & Video – “Let’s think beyond the camera-mounted microphone.”
If you are taping an interview in a quiet room such as the College TV studio with the camera on a tripod two feet in front of the person being interviewed, then the microphone in the camera will work just fine. At the other end of the spectrum would be the extreme difficulty of recording the dialogue between two basketball players running down the court after the go-ahead shot during a championship game. They’re moving and panting in a delirious sold-out gym.
How many microphones do you need?
One? One for each actor?
How will the sound be captured?
The shotgun or boom mic could be directly fed into the camera, preferably through the bigger XLR and not the smaller mimi jack. Or several lapel mics could be run through a mixer and that output fed into the camera, again preferably through the XLR connection. Or the sound could be recorded separately and then synced with the video. If each voice is its own computer file (.wav or .mp3, for example), then you can compensate for almost any problem with the software during post-production.
For concerts, live music, and situations were the sound will be seriously loud, see whether you have a Mic Attn (microphone attenuation) setting. Switching to it will cut the level of the sound before it reaches the tape.
Check the levels Always wear a set of headphones and check the sound before pressing record. Check the audio levels. They should peak at around minus twenty decibels. If the levels are too low adjust them manually, get closer or ask the actor to speak up.
Distortion If the source is very loud, the audio levels will go off the scale. This tells you the sound is distorting. This is a bad thing and cannot be cured later. To avoid distortion switch the control on the audio panel to Mic Attn. This will cut the levels and stop distortion.
- add the voices later either by dubbing (matching the orginal) or voice-over.
- plan on video that doesn’t need voices.
Where will you place the mics?
The one could be on a boom held toward or over the actors. Each actor could have one clipped to a lapel. Those clip mics are also called lavalier mics or lapel mics.
When you arrive at a location check it for noise. Try to eliminate any unwanted background noise. If it’s still too noisy, go somewhere else. If you have to shoot in a noisy location, show the vierer why it’s noisy. For example, show the cars in the shot so that the viewer can identify the source of the traffic noises. This helps the viewer focus on what is being said.
Types of mics
Some clip, radio, reporter microphones record sound from all directions. If you use them, be careful about extraneous sounds on the set or location.
Directional microphones like the shotgun mic register sound coming from in front of the microphone. They pick up less background noise, which is useful when filming in a noisy area.
Stick microphones are good for conducting interviews on camera. But they cover an arc of sound from all directions so they need to be close to the source.
Clip microphones are designed to be clipped to the contributor’s clothing. Like reporters mics they are omni-directional and need to be close to the source. Clip mic’s pick-up close sounds. Clothes rustling and even heavy breathing can be a problem. So be careful where you clip them.
Gun microphones are directional. This means they pick up a narrow beam of sound from in front of the microphone. All mics are sensitive to wind blast. With a gun mic a foam or fluffy shield should always be used when outside. Gun mics are best operated on a pole. They are great for reacting to spontaneous action. The microphone must always be pointed at the person talking. And be careful the mic doesn’t drop into the shot. Learn where the edge of the frame is.
More information on microphones
Simply DV’s Sound Sense. See “What NOT to do with a mic”
Pandora’s Tips for Mics
DV Info’s Troubleshooting
DV Ccreators’ Common production audio killers