Audio Acquisition for Photographers
By Ron Dawson
Have you ever seen “The Greatest American Hero?” It was an ’80s television show in which a mild-mannered teacher is visited by aliens and given a suit that gives him super-human powers, but he doesn’t know how to use it. Instead of looking heroic when he flies, he flops and flails as he zooms through the air.
As a filmmaker who does quite a bit of work in the professional photography industry, I get to see a lot of videos shot by aspiring photographers-cum-filmmakers. But like the hero, they have this powerful filmmaking tool in their hands, but they aren’t quite “flying right.”
With the flood of HD DSLR cameras, many of you have taken on the role of capturing video segments to enhance your artistry. This article will help you with one of the most crucial aspects of video production: audio acquisition.
AUDIO CAPTURE: Perhaps the single most prevalent issue I’ve seen with HD DSLR videos by newbies is poor audio acquisition—the audio recorded and used in the final production. Many photographers are using only the on-camera microphone for audio acquisition. The resulting end product sounds echo-y, or there’s significant obtrusive ambient noise (air conditioners, traffic noise, extraneous conversations). Even if you use a directional microphone like the Rode (a popular choice), you don’t always get the best results.
The reason is that the audio captured by DSLR cameras is highly compressed, and in many models there is no way to control the audio recording level. Many DSLRs are set to auto-gain, which means the volume of audio you record will go up and down depending on how loud the source is. If the source is very soft, the camera will automatically boost the levels and you get a hissing background sound, which is to audio what visual noise is to a high ISO setting. Some of the cameras (like the Canon EOS 5D Mark II) have released firmware updates that at least allow you to set your audio levels. But even so, you still get the compressed audio issue and that echo-y sound.
The Zoom H4N is a popular video recorder choice
for filmmakers and videographers.
To avoid this problem, you must use a dedicated audio recording device that records audio to a separate form of media. A popular choice among filmmakers and videographers is the Zoom H4N digital recorder ($299). The Zoom has a great built-in mic that is directional; or you can connect an external microphone. Most professionals use an external mic in one of two configurations. One is a wireless system where the transmitter is on the person to be recorded and the corresponding receiver is connected to the Zoom. Or, if you’re moving around with the camera and have a DSLR rig, you can attach the Zoom to the rig, or hang it over your shoulder with a strap, then attach a directional mic like the Rode. (Read Ron Dawson's Zoom H4N review.)
The Zoom, as well as other similar digital recorders, records audio to an SD card. A 1GB card can record about 90 minutes of 48k/16-bit audio (a commonly used audio setting for video). The Zoom can record in high quality, uncompressed .wav files, or compressed .mp3 files (suitable for quickie podcast interviews).
It’s not always imperative to record audio to a separate device. Consider how the audio will be used. There are some situations where the audio directly from the camera, used sparingly, will work fine within the context of a larger production. Examples include bridal preparations or portrait shoots. However, for crucial moments like vows, toasts, or longer interviews for documentaries, you must use the proper equipment to get quality audio.
The clapboard (also called a slate) gives you an audio and visual cue to synch at the beginning of the shot so that your sound and video match. ©Ron Dawson
GET IN SYNC: If the video is recorded to one card, and the audio to another, you have to get them to sync up when you’re editing. The most common way is to create a visual and audio cue that you record at the beginning of each shot. You’ve likely seen behind-the-scenes specials where someone holds a black and white clapboard in front of the camera, says something like “scene one, take one,” then claps it. That’s not just for show, it’s a sound sync. The editor will match the audio sound of the clip with the visual of the clapper coming down. You don’t have to have clapboard though. You can accomplish the same result on your production by just having someone physically clap their hands once loudly.
There is also special software to sync audio with video, like Singular Software’s Plural Eyes. It takes audio from two sources (in this case the audio file from the recorder and the audio portion of the video recorded by the DSLR) analyzes them, then synchronizes them for you. If you have a lot of clips that need to be synced, or if you have videos from two DSLRs that were running simultaneously, or if you were unable to record a clap, a program like Plural Eyes will make your editor’s life much easier.
Combine audio from funny toasts with corresponding video footage to tell a story. ©Ron Dawson
IT’S ABOUT THE STORY: The work I do as a filmmaker is that of a storyteller. The video and audio I record are just the media I use to tell that story (just as the photos you create tell a story). When you go into the editing room to put all the video and audio together, keep the story in mind. How can you mix and match the audio recorded from the various events and people, with various parts of the video to tell a more powerful story? If you’re shooting a wedding, don’t just show the father of the bride giving his traditional toast. Cut away to a shot of him walking the bride down the aisle as he talks about how he felt giving his “little girl” away (creating a flashback). During the vows, when the bride is telling her groom how much she loves the way he makes her laugh, cut to shot of her laughing at something he’s done. As the director and producer, it’s your job to look (and listen) for these little moments and weave them together in a way that’s emotional, moving, and meaningful.
How you use and manipulate audio in your productions (including the music selection) will make the difference between you looking like Superman, or “The Greatest American Hero.”
Ron Dawson is an international award-winning videographer, filmmaker, speaker, and author of "ReFocus: Cutting Edge Strategies to Evolve Your Video Business" (Peachpit Press 2009). You can follow him on his blog at bladeronner.com.