Anyone can capture great audio for their videos in the comfort and safety of a studio. But what happens when you pack your camera bag and head outside? It's a big, noisy world out there, one not particularly friendly to the needs of the field videographer. Need proof? Put a finger to your lips sometime, and try to shush the world. It doesn't work.
Instead, you have to learn to overcome imperfect recording locales with your savvy and creativity. Notice I didn't mention equipment. In the final mix, the gear you use is much less important than the tricks and techniques you employ. To get you started toward great “guerrilla” audio in the field, here are half-dozen techniques you can put to use in your next video shoot.
1) Always monitor what you're recording
This may seem too obvious to mention, but it's amazing how often videographers simply trust that their sound is being captured correctly. They happily shoot away with only the occasional glance at their record levels, assuming that great audio awaits them when they get back to their computer. But what if it doesn't? If you're not making sure the sound is being recorded properly, you're oblivious to any number of audio maladies that might ruin an otherwise perfect shot (or whole shoot).
WITHOUT MONITORING AUDIO AS YOU SHOOT, YOU CAN'T KNOW THAT
* a car with a high-powered ham radio drove by and swamped your wireless mic signal mid-take
* your boom mic's battery is dying and the audio is distorted
* a cable jiggled loose and what you see on your audio level meters is more hum than sound
* the computer under your interviewee's desk is nearly as loud as his voice
* and so on....
You wouldn't dream of shooting without looking at your viewfinder, right? The same principle applies with sound. In this age of the ubiquitous earbud, you have no excuse for not monitoring your audio as you shoot. You can't fix what you can't hear.
In the final mix, the gear you use is much less important than the tricks and techniques you employ.
2) Use manual record levels
Automatic record levels (or auto gain) are great if you're in a bind and can't set your levels manually. But they're always a compromise, and auto gain leaves telltale fingerprints on your audio. If someone stops speaking for a few seconds, you'll hear background noise creep up as the auto gain circuit tries to fill the meters with something. When a loud sound hits the mic, the auto gain circuit will usually overreact and leave a drafty quiet spot in your recording. These artifacts are often more pronounced when you're out recording in the field.
Setting your audio record levels manually avoids these problems and a host of others, and the process is straightforward with most cameras. Simply engage manual audio levels, have the sound source do what it does, and set the sensitivity so the loudest sounds peak at about -6 dB. If you're recording something really erratic, peaks at -10 dB would be more forgiving. If your camera has an audio peak limiter, engage it.
The main drawback of manual levels is how easy it is to forget to adjust them if you change your sound source or mic location. If you forget, your audio could be too quiet, or overdriven and distorted (which you'd catch immediately thanks to tip #1, of course). Setting levels manually also takes time, which can make this a poor choice if you're shooting on the go.
3) Get creative with mic placement
Don't get caught in the “camera, boom or body” rut of mic placement. Look for other strategic locations that would make a better spot for a mic. This is especially helpful if you don't have a boom operator or shotgun mic. All you have to do is find a place for a mic that's close to the sound source and invisible to the camera.
Stash a lavalier mic behind the salt and pepper shakers on a restaurant table, or in a potted plant by the couch. Hang a mic on its cable from a tree limb just over your actors. Put a wireless lav's belt pack in a light fixture and dangle the mic over your speaker. Put a mic on a short stand just behind a piece of furniture. You get the idea—any place is fair game to pick up audio. Remember: if the lens can't see it, it doesn't exist.
4) Use a compact audio recorder
This tip requires breaking out of the mindset that you have to capture your audio with your camera. You don't. Any inexpensive, compact digital recorder will record clean audio that you can easily drop onto your timeline. As with tip #3 above, there's no limit to where you can hide a recorder in the field to capture up-close audio.
I once needed dialog from a long, telephoto shot with five actors, and I didn't have the usual audio gear to pull it off. So I hid my audio recorder behind a patch of tall grass and pointed it straight up. The actors walked up, hit their marks by the recorder, said their lines, and walked past. The resulting audio was fantastic. Did I use auto record levels? Yes. Could I monitor the recording in real-time? No. Was there a simpler, more elegant solution? I can't think of one.
BONUS TIP: use that compact recorder to grab sound effects, backgrounds and ambiences you can use to enhance your video and smooth your edits. Have it with you all the time, and you'll be amazed at the cool sounds you can record and use later in your productions.
5) A physical solution beats an electronic one
Just because you can engage a wind filter or run a noise reduction plug-in or apply corrective EQ doesn't mean you should. Such trickery almost always has a downside. Instead, change your mic'ing setup or environment to improve your audio.
Wind buffeting your mic? Don't engage the wind filter, since it wipes out your bass response and results in a thin sound (which will still have wind noise). Use a wind sock or foam filter. Is your mic picking up the swish of an air conditioner or fan in the next room? Roll a towel to close off the gap under the door. Is the clock on the wall ticking loudly? Take it down and move it. Shooting in a doctor's office? Orient your directional mic away from the burbling fish tank. When you can avoid major audio wrangling in the edit room, you'll end up with better sound in less time.
Remember that you can't fix what you can't hear, and this principle applies before you shoot, as well. Use those headphones or earbuds and really listen to what the mic is picking up in the space. This bypasses your brain's natural ability to ignore background noises, allowing you to hear what needs your attention. Pros start by listening intently because they know it's better to fix it now than to fix it in post.
6) Closer is better
I saved the most important tip for last. In almost all cases, getting your mic as close as possible to your talent is the #1 improvement you can make for better recordings. For clean, crisp speech in challenging environments, a $50 mic two feet from the sound source will usually sound better than a $5,000 mic 10 feet away.
It's simple physics. As you move a mic closer to a sound source, its volume increases exponentially relative to other sounds. Stated in the reverse, background and competing noises decrease exponentially as you move a mic closer. Even if there are no competing noises, a closer mic will pick up less room reverb and echo when shooting indoors. Moving your mic closer is like reaching for an imaginary knob marked “audio clutter” and turning it down.
Getting the mic closer also allows it to pick up those delicate high frequencies that make speech crisp and articulate. If you want “high-definition” sound, you'll usually find it within a few feet of your sound source.
FIELD TRIALS
The world is a harsh, noisy place that seems to take pleasure in compromising our audio recordings. But you needn't fear it—you can overcome audio challenges with your ears and your brain. Venture forth, brave videographer.
