There are three major weaknesses to recording audio directly into any Canon or Nikon DSLR camera: there is no way to see levels while recording, you cannot listen on headphones, and there is no good pre-amp or phantom power (to power a microphone) built into the camera. It is my guess that all of these issues will be addressed in some way by the manufacturers in the near future, but in the mean-time, here is my solution:
I use an external audio recorder such as the Zoom H4n or the Tascam DR-100. I then use a step-down cord (from Sescom), to run a signal out of the recorder into the camera’s mic jack. This solution allows me to put the best possible audio into the camera and also creates an external audio recording in case anything goes wrong, like a cord connection coming loose. Otherwise, without visible recording levels or headphone jacks, there is no way to know for sure if you are getting anything in the camera. I find that more than 90% of the time the audio I send into the camera works fine and I can avoid having to sync the external audio recordings.
Let’s talk about the Sescom step-down cords for a moment. In general, line level is an amplified signal and mic-level is an un-amplified signal, meaning much less power is running through the line. If we run a line-level into the mic jack on the camera, the sound level will be way too hot to record. Headphone level is not quite as hot as true line level, but still too hot to run into mic level. Therefore, Sescom makes cords appropriate to the individual device. The Zoom H4n does not have a line-out jack, so we are trying to take a signal from the headphone line down to the camera and also use a splitter so that we can still listen on headphones. They make this cord that is set to the right level and has a built-in splitter for headphones (note that -25dB is the amount that headphone level gets stepped down to get to mic level):
In the case of my Tascam DR-100 (and many other recorders), there is a line-out jack in addition to a headphone jack. In that case, Sescom makes this cord (not splitter necessary and -35dB is the amount the signal gets stepped down):
In the case of using a Zoom H4n and a shotgun mic, running audio into a Canon 5D Mark II, 60D, Rebel T3i (600D)—where you have manual control of audio—and using the Sescom patch cord (providing a -25dB step down), follow these steps:
1) Set an input level to achieve a proper level where your peaks are maxing between -12 dB and -6 dB (and never hitting 0 dB).
2) Set the headphone level quite high, between 90-100, then don’t ever adjust it! If you have this level set too low, you can actually end up adding hiss to your in-camera recording. (When using a recorder such as the Tascam that has a line-out jack, you skip this step).
3) Use the audio preview levels inside the camera to adjust the levels to exactly match what you are seeing on the recorder. Once this relationship is set, as long as you don’t adjust you headphone out level or the level inside the camera—then the level you are seeing on your external recorder should be approximately accurate. In other DSLRs that do not have a manual level setting you can skip this step (I would recommend running your own tests in the case of the Nikons that have High, Medium, and Low pre-sets).
Then when you work with a wireless lav mic, there are two additional places to set a correct audio level:
1) Mic sensitivity level on the transmitter.
2) AF Out on the receiver.
One final tip: when I work in this way, I leave the recorder recording all day long and only stop and start the camera. Audio files are relatively small and I want to keep it simple when it comes time to catch a shot and not accidentally forget to start my recorded.
I mount the recorder above the camera using an inexpensive bracket from Custom Brackets (approx. $40). There are dozens of manufactures who make more expensive rigs for DSLRs. I tend to shoot as much as possible on a tripod, so I find my simple bracket works well in most cases. It also gives me a place to mount my shotgun since it frees the hotshoe as a place to mount my wireless receiver.
As for solving the pre-amp issue, the Tascam is a tiny bit cleaner than the Zoom (based on reviews at transom.org—I haven’t been able to discern a difference). However, neither is great. My next solution is to look into a pre-amp upgrade to the Tascam from Oade Brothers. Powered mics are another solution (such as the Rode NTG-2—but this is not necessarily the cleanest possible audio).
Wes Pope is a Lecturer at Northern Arizona University, where he teaches in the Photojournalism & Documentary Studies program. Formerly, Wes was a photo and video journalist for 15 years and recently earned an MA in Documentary Film and History from Syracuse University. This post is excerpted from Video Journalism for the Web: A Practical Introduction to Documentary Storytelling by Kurt Lancaster (Routledge, 2012).