Can I use my phone to record film audio?

Yes, with a lav mic or a small external recorder. The phone's built-in mic is too far from the mouth for clean dialogue, but a wired lav clipped to clothing works well.

Do I need a shotgun mic?

Not always. A boom-mounted shotgun is ideal for exteriors and moving shots. For interviews and static scenes a lavalier is simpler and often cleaner.

What sample rate should I record at?

48 kHz, 24 bit is the film standard. Stick to it for everything unless you have a specific reason to record higher.

7 min read

How to get good audio when filming, even on a tight budget

Three feet from the mouth, out of the wind, and with a scratch track for sync. The rules that save every first film.

The most common reason a beginner film feels amateur is not the camera, the lighting or the edit. It is the sound. Audiences will forgive a shaky frame or a flat grade. They will not forgive muffled dialogue, hiss, wind blasts or audio that drifts out of sync. The good news is that clean audio is cheap. You just need to respect a few physical rules.

Get the microphone close

Distance is the single biggest factor in clean dialogue. A shotgun mic on a boom two feet above the actor's mouth sounds fuller and warmer than the same microphone five feet away, and it picks up far less room and background noise. If you can only afford one technique, get closer.

A smartphone lavalier two feet from the mouth is often better than a professional shotgun six feet away. Proximity beats price.

Record a scratch track on camera

Even if you plan to sync external sound later, let the camera record its own microphone. This scratch track is what waveform sync algorithms compare against. It also gives you a backup if the external recorder fails.

Turn auto gain off on the camera if possible, otherwise dialogue will pump up and down.
Lower the camera mic level so it does not clip on loud lines.
Keep the camera mic enabled even when it sounds terrible. Terrible is enough for sync.

Protect the microphone from wind

Wind is the fastest way to ruin a take. A foam windscreen helps indoors. Outdoors you need a furry dead cat or a blimp. If you have neither, put the body of the mic between the capsule and the wind, or use a jacket as a makeshift barrier. Never blow on a mic to test it.

Watch your levels, not your hopes

Record dialogue with peaks around minus 12 dBFS. That leaves headroom for shouts and laughter while staying well above the noise floor. If peaks are constantly hitting zero you are clipping, and clipped audio cannot be fixed. If peaks are below minus 30 dBFS you will hear hiss when you raise the volume later.

Sync before you edit

Import your external audio and your camera files, sync them by waveform or clap, then replace the camera audio with the clean track. Do this once per take, not once per edit. The tools on this site let you inspect WAV metadata, convert sample rates and split poly files before you open your NLE.