Recording documentary audio on or off camera?

[Pete Brady]

Hi,

I've checked out the forum a bit for this answer but I think I still need some opinions.

I will be taping some interviews for a documentary next month. The interviewees will be sitting in a controlled audio environment (a radio station studio) I'll be using a shotgun mic and boompole to get the audio and using my XL1s for the video. I am doing the edit-down so there is no problem with a client asking for a specific format.

My question is should I go direct into the XL1s for the audio or use my G4 laptop and MBox to record the audio and just use the on-camera mic for pickup for sound sync? I am not as familiar with the XL1's audio specs as I should be (most of my recording I've done with the XL1 to this point has been music videos, synched to the playback.)

Any and all opinions are appreciated - thanks!

--pete

[Douglas Spotted Eagle]

If it's dialog-only, and you have a good mic setup that you can monitor on site, I'd certainly use the camera and not add the hassle of a secondary device. The XL has good audio specs for external plugged in audio. Do you have a Sound Devices or Beachtek box for a pre? Not necessary, but useful. What mics are they? Boom operator know what she/he's doing?

[Pete Brady]

Hi Douglas,

Thanks for the information -- yes, I would prefer the "less equipment to move" setup! :)

The mic is an AT-897 shock mounted on a Gitzo pole. The boom operator is not very experienced but pretty good.

I don't have a preamp for the mic. Would you suggest something like the beachtek DXA-4?

--pete

[Jay Massengill]

I agree, the XL-1 is capable of good audio for dialog. The key to success is using the right interface and the correct audio levels.
The MA-100 and MA-200 seem to be plagued with electrical noise from the camera, I'd rule them out.
The SoundDevices MixPre works well over a short distance using the unbalanced -10db line output hooked to the camera's rear RCA connectors.
A small Mackie mixer will work well too since AC power will be available. However, the Mackie RCA outs are about 0db level. It is fairly easy to overdrive the camera input with these if you don't set the mixer a little lower than normal.
What mic are you using and what other equipment do you have available for interfacing and monitoring?
If it's an important project it is good to record a backup, but i'd put good effort into getting what you need into the camera. It will save a lot of hassle in post.

[Jay Massengill]

You beat me to the punch. If this is a static situation, I'd mount the boom on a stand. The boom op can still attend to the boom and monitor sound, making adjustments if needed. Unless these are very short interviews or you're moving around or there's more than one person being interviewed simultaneously, you could really benefit from a static boom. Many times interview footage is edited out of sequence, so having uniform audio throughout will reduce changes in audio at the edit points.
The AT897 is a good mic, but it's not as highly sensitive as others like the K6/ME66 or the AT4073a. With a device like the DXA-4 (or the much better DXA-6), you can't get any additional gain from the mic, you can only attenuate. The new DXA-8 does have a preamp function and should work pretty well.
One more question: How wide do you envision shooting? Will there be many environmental type wide shots? Even with a controlled audio environment like a studio, you'll need to keep the 897 fairly close to the interviewee for good sound. This may influence your visuals if you don't want the mic to appear.
If these are single-person interviews, I'd also suggest renting or buying a good wired lav mic and use it and the shotgun on the interviewee. Even if you're shooting multilple interviews, it only takes a minute to run the mic cable under the shirt and place it properly. That way you have your choice of close lav or more open shotgun (or a proper combination of both). Basically this gives your most effective "backup", because you're recording two separate audio signals.

[Pete Brady]

Hi Jay,

There will be no environmental shots (with audio anyway) in this part of the documentary. This is single person interviews, close-in head shot ("60 minutes" style.)

I do have a smaller boom stand that I use for voice-overs in studio that could probably be used in place of the boompole. I might even spring for the 4073a since I do like the sound from it.

If I go the dual-microphone route, I almost feel like I should go back to using the laptop with the Protools MBox since that does have gain control (and I already own it!)

[Jay Massengill]

The 4073a is definitely in a different class than the 897. It does require phantom power though, so you'd need to use the mbox or if going to the camera only you'd need an additional phantom source. The DXA-6 and DXA-8 have phantom power.
If you record to the mbox you could route the zero-latency analog outputs back to the camera. I think you'd have to attenuate them though to keep from overdriving the inputs.
At the very least you must record some audio on the camera in order to log the tapes and achieve manual sync when editing the audio and video together from both sources. You can use the on-camera mics if you have to, but obviously that wouldn't be useable as a high-quality backup, only an emergency backup.
Does your powerbook make much noise when running? It could be a concern depending on how large the shooting space is.

[Pete Brady]

Thanks again for your help Jay! I chewed through the whole thing and decided to do the following:

For this shoot, I'm borrowing a friend's K6/ME66 and lav setup. I am buying a DXA-8 to use with the XL1s and will run both mics into the -8. This does two things for me: I save a little money right now and get to try out the ME66 setup. I have used Sennheisers in the past, so I will see if I like it vis. the 4073a. If I am not wild about it, I still have time to get the 4073a before the shoot and just use my friend's lav mic.

--pete