Sound
On Set
Film is equal parts sight, sound, and motion, but technically bad audio is the fastest way to lose your audience. No one cares if your focus is a bit out, or your camera shakes too much, or your VFX isn't seamless. But tech issues on the audio will break their brains, and by extension, their ability to enjoy your work. Here's everything you need to record clean dialogue on your first shoot.
Get The Mic Close
Every time you halve the distance between mic and mouth, the dialogue gets four times stronger against the room. There's a reason boom mics have a habit of making their way into shot: you want any mic to be as close to your actor as possible.
Drag the boom mic toward the actor (or use ← → keys). Watch, and hear, the dialogue rise out of the room noise.
Pickup Patterns
Every mic has a polar pattern: the shape of where it listens. Some mics let you change this, which drastically changes how the mic behaves. You need to be aware of it, because if "where the mic is listening" and "where the sound comes from" aren't the same, you may as well pack your bags and go home. Tap a pattern, then drag the source around it.
The tighter the front lobe, the more room it rejects, but the harder it is to aim, and the more you must mind the rear lobe.
Tighter is not always better. A narrow pattern rejects more room but punishes bad aim and drifting actors. On a chaotic set, a slightly wider pattern you can actually keep on target beats a tight one you keep missing.
Mind the back. Super and hypercardioids hear behind them. Point the rear lobe at a noisy fridge or an open window and you've invited it into the take. Aim so the dead zone faces the noise.
Shotguns hate small rooms. That long beam is built for outdoors and big spaces. Indoors, the reflections it grabs off hard walls can sound worse than a plain cardioid. Match the pattern to the space.
Pick The Right Tool
The three most common mic types you'll want to use.
Shotgun
Lives on a boom pole, just out of frame. Narrow pickup rejects the room. This is how most indie dialogue gets recorded.
Lavalier
Clipped to the chest, hears in every direction. Great for wide shots and moving actors. Hide it, and always record it as a backup.
On-Camera
The mic built into your camera is too far away by definition. Use it for sync reference, never for the final dialogue.
Drag the ● sound source around the mic. Brighter waves mean stronger pickup.
Aim For −12 dB
Set your recorder so dialogue averages around −12 dB and peaks near −6. Too low and you'll fight hiss in the edit. Hit 0 dB and the take is destroyed, because clipping cannot be fixed. Try it:
Find the gain where the loud words land in the orange target zone, and never touch red.
Boom Basics
From above, pointed at the chest. Overhead booming sounds natural and keeps the mic out of eyelines. Aim the barrel at the sternum, not the lips.
Ride the frame line. Get as low as the shot allows. Ask camera for the frame edge, come in until you break it, back off two inches. That's your spot.
Watch your shadow. Booms cast moving shadows across faces and walls. Check every lighting setup before you roll.
Silence the operator. Rings off, sleeves quiet, grip loose but steady. Cable wrapped around the pole so it can't slap.
Sneaky Noise Makers
Stand in your location, close your eyes, and listen for thirty seconds. What do you hear? Is it something that's appropriate for the environment of your film, or is it contamination? Hunt these down:
Fridges & freezers. Unplug them, and put your car keys inside so you can't leave without plugging them back in.
Air con, fans, heating. Off during takes, back on between setups. Your actors will forgive you.
Phones. Airplane mode for everyone on set. A buzzing phone near a mic cable ruins takes invisibly.
Wind. Outdoors, a bare mic is unusable in any breeze. Always fit the furry windshield, the deadcat. It's not optional.
Echoey rooms. Bare walls and tile bounce sound. Hang blankets and duvets just out of frame. Ugly on set, invisible on screen.
Phone, Or A Real Recorder?
A really common mistake when you're starting out recording sound is forgetting that you need a recorder. A mic by itself is useless. But your mobile phone can record, is that good enough? Yup, probably, when you're starting out. Ask the mystic recordatron 5000 below and your path will be revealed.
The phone path. A decent mic into a phone recording app is a real, usable setup. Modern phones capture clean audio and the mic does most of the work. This is the right starting point for most first films, and the money goes where it matters: the mic.
You need an adapter. Phones don't take a professional mic directly. A small interface (something like an iRig or a USB-C audio adapter) bridges the mic to the phone. Budget for it: it's the cheap part.
The recorder path. A dedicated field recorder (Zoom, Tascam, Sound Devices) earns its cost when you need more than one mic at once, real physical level knobs, timecode to sync with camera, 32-float safety, or reliability across a long shoot day. It's a tool you buy once you keep hitting the phone's limits.
The rule of thumb: spend on the microphone first, always. Reach for a recorder when a specific limit is blocking you, not before. A great mic into a phone beats a cheap mic into an expensive recorder every single time.
Bit Depth Isn't Resolution
Bit depth is basically "how much of something can you record?" Not duration, how many hours, but depth. What's the range? Can you capture the quietest whisper and the loudest scream accurately?
Bit depth is a discussion point in both video and audio. In video, you need range to capture the brightest brights and the darkest darks. The equivalent in audio is the noise floor, the quiet hiss under everything you record, and the headroom, how far a sudden loud moment can go before it clips. More bits, more room at both ends, which means more freedom to change it in the edit.
Slide to rescue a take recorded wrong. Push a quiet line up and watch hiss rise on 16-bit. On 32-float, drag past the ceiling on a loud take too: nothing ever breaks.
16-bit. CD quality. Fine for a finished mix, too shallow for capture. Any level mistake shows up as hiss when you fix it. Don't record dialogue here.
24-bit. The professional standard, and free. Same file, same mic, just a menu setting. Deep enough that normal level mistakes recover cleanly. This is your default.
32-bit float. So much range that clipping effectively stops existing. Set levels roughly and a blown-out shout or a whispered line both come back in the edit. Needs a more expensive recorder.
Record Room Tone
Before you wrap any location: call "Quiet for room tone", and record sixty seconds of everyone standing still in silence. That recording of "nothing" is what your editor uses to patch gaps, hide cuts, and smooth dialogue. Skipping it is the number one rookie regret. It costs one minute. Always do it.
The On-Set Checklist
Headphones on. you monitor every take, no exceptions. If you didn't hear it, you didn't record it.
Mic as close as the frame allows. ask camera for the frame line.
Levels checked on the loudest line. have the actor deliver their biggest moment, set peaks near −6 dB.
Noise hunt done. fridge, AC, phones, wind protection.
Recorder actually rolling. say it out loud: "Sound speed." Check the timecode is counting.
Room tone captured before leaving. sixty seconds, everyone frozen.