I feel some people treat sound as a secondary source of information when it comes to video. Video is all they think about. How will it look? did you get that shot I was looking for? Don’t get me wrong video is quite essential sometimes more than video.
This short blog is to help educate people on sound and why you need different tools for different situations. Down below is a video I shot to demonstrate my point of view. I wanted to show how using a microphone placed on top of the camera is inferior to that of a microphone placed above the talent (12 inches above) just out of camera frame. You would use this method when you interview someone.
Simply using a microphone that is placed on your camera to record your talent’s audio will sound hollow. The farther the mic is from your talent the less signal (his/her voice being the signal) you will get. This is called the signal to noise ratio. The farther away the voice is, the more noise will be introduced into the audio signal. You want the voice to be as close as possible without causing a proximity effect, this is when the microphone is very close to the talents’ mouth which in return creates a more bass sound response.
So, for an interview setup, I prefer the mic to be as close to my talent as possible. You can clip a lavalier microphone on your talent’s shirt or jacket and that will yield satisfactory audio. However, you will more than likely see the little microphone pinned to the talent’s shirt. I like to use a boom mic and place the microphone just about 12-18 inches above my talent. This allows me to record their voice without showing the microphone. Another reason I like this approach is you do not have to place anything on your talent. Sometimes that can be awkward, especially if you are a male videographer and have to place the lavalier microphone on a female interviewee. Plus, you must hide the cord if you are not wireless.
They make a variety of boom mics for conducting interviews. I use a hyper cardioid mic which works great indoors. There is less room reverb with a hyper cardioid. You can use a boom stand to hold your microphone or a light weight microphone tripod stand. These are just few things to consider when recording an interview.
1.Microphone on camera not good
2.Lavlier microphone on interview decent
3.Boom mic place above interviewee best option in most cases
Here is an audio example of me recording audio with a mic on the camera vs a hyper cardioid placed above me. Listen with headphones, you will hear the difference.