Boom microphones have long reigned as the superior choice for filmmaking. Why? A few reasons:
- In double system sound recording, the microphone works independently from the camera, so that noises made by the camera or operators are not recorded in the sound file.
- It has a long pole that allows “easy” access to the sound source. Boom operators often have a very specific sound they are trying to capture. The most important one for narrative films is, of course, dialogue. With its long pole, the microphone can be suspended overhead, above actors. Additionally, if the sound source is on the move (like a walking actor), operators can follow them with the microphone.
- It is highly directional, meaning that it has a narrow pickup pattern. This allows the operator to isolate the other unwanted sounds. For instance, while recording dialogue next to a busy street, the boom operator will aim the microphone away from street to avoid noises.
- Most professional boom mics sound better than any built-in mic your camera may have.
Boom Microphone Tutorial: How to Operate the Boom Mic
Know the frame lines: When hear the sound recordist asking, “Where’s the frame line?” they want to know what the camera sees so that they can make sure not to “dirty” the frame with the boom mic. The goal is to bring the boom mic as close to the sound source (usually the actors) as possible without intruding the frame, which is why you always want to know where the frame lines are.
Pivot with your subject: Usually in narrative films, you have two or more actors engaging in conversation in a scene. Sometimes it is necessary to pivot the microphone between all the speaking actors.
Aim away from unwanted sound: Because boom microphones are directional, they are also very powerful — they can pick up sound from several feet away. So it’s important to separate the sound (wanted) from the noise (unwanted) by pointing it at the right direction.
Be careful with shadows: although the camera operator will let you know if you dip the microphone in the frame, the shadows are a subtle affair. Be mindful of shadows cast by the pole and cord in the shot. They could go unnoticed on the set, becoming a huge headache during editing.
Be easy on the pole: Bear in mind that the entire recording apparatus becomes conductor of sound. It is probably a bad idea to wear rings while operating the boom. Also, if you support the pole on your back or against your body, be careful with clothes rustling.
Here’s a great video tutorial from Lynda.com with even more tips: