What the hell happened?
 

Okay, I had a shoot last night. This guy who speicializes in audio brought along a mixer. We didn't have the correct adapter to plug it into the XLR inputs on my MA100, so we took his quarter inch plug and put it into the quarter inch input on the camera, where the onboard shotgun plugs in. When he listened in the headphones, he got audio signal, and I could SEE it on the mixer's VU meters. However, when I went home to look at the tape, NO AUDIO AT ALL! What'd we do wrong? Was I supposed to select line level for the input, instead of MIC? Does the quarter inch thing just not work that way?

No idea Josh...

It sounds like you had everything right, especially if you heard the audio in your headphones.
How where you holding your tongue while you were recording?

P.S.- Congratulations on your millenium post!

The sound guy heard the audio in HIS headphones, which were connected to the board, not the camera.

As a precaution, you should have headphones on the cam. If nothing else, just to make sure you are getting the audio.

Josh, I have no real idea what I'm talking about but I've heard of a thing such as both channels being out of phase when you connect certain devices, such that they cancel each other out and give you no sound, even though it looks like it's ok. I'd ask on dv.com in the audio section, I'm sure Jay will know something that it might be.

Cheers
Aaron

I appreciate that. Dv.com doesn't seem to be real good at answering its posts, though. I see a lot that have been up for at least a week, and have no response.

And if that phase thing is the case. . .is there any chance in hell that I might be able to do something that would recover the audio. . .I hope that didn't sound really stupid.

I had a shoot where we recorded the sound through a mixer and then when we played the camera tape back the audio was almost gone. I had to turn the volume way up on the tv and it was barely there. I couldn't belive it because we had been monitoring the sound off the camera the entire time. Then on playback we had nothing and I thought the whole track was gone.

What I found out was that if I ran the camera tape audio back into the mixer it sounded great. Totally crystal clear. So I ran the track back through the mixer and recorded it again on another camera and it tracked great and worked.

I don't know what happened that it seemed lost but it may have been a phase issue like mentioned before. Try and get a hold of that mixer again and see how the tape output sounds going back into the mixer.

Ben Lynn

Have you tried looking at the digital values for the captured audio data? You might be able to invert a phase on one channel in Sound Forge and recover the data.

Otherwise it sounds like you had a bad switch setting, or the jack not plugging in enough.

I always have the sound engineer get his reference from the camera when that's the audio recording medium. You never know what noise might show up between the mixer and the camera--very typically, dirty AC can sneak in, or a nasty ground loop will rear its ugly head, if the camera is plugged into the wall (vs. running on battery).

Thanks Rob. It was my damn fault, I had "audio one" selected on the camera, rather than "mic or mic att," and since it was plugged into the same place as the onboard shotgun, it should have been either "mic" or "mic att." I was misled by the mixer, and figured the reason I wasn't getting any readings on my VU meters had something to do with the way we hooked it up (which it did, but not the way I thought).

So just to make sure, any time audio is being recorded to the tape, or camera, for that matter, it WILL show up in the VU meters, regardless of whether it goes through a mixer or anything else?

Affirmative.

And by the way, don't feel bad. It's happened to the best of us. After shooting for awhile, you start to accumulate a mental checklist just based on all the blockheaded screw-ups you've made in the past. So mistakes are useful.

My personal best botch job came when I accidentally left the camera on field mode for some important reshoots, when the rest of the movie had been shot in frame movie mode. That, combined with the fact that we had to shoot with available interior light because we couldn't get back the extensive lighting equipment for the reshoot, impelled the (locally renowned) cinematographer to decline his DP credit on the project. How embarrassing.

(I smell the opportunity for a whole new thread in the TOTEM pole.)

Thanks guys. Thankfully, this was not a paid gig (few of mine are hahahahahhahaaha. . .now I'll cry), no real deadline, and we can fairly easily do the MOS thing, with one camera to play the footage and one to record the actors.

And, "affirmative" to which of my queries? That if I'm using something plugged into the shotgun's input, the "mic" setting on the camera needs to be selected, or that any audio recored on tape in the camera will show up on the VU meters? or both?

The latter.

In that case, what should the switch be on for anything that uses the quarter inch (or 8th inch, whichever's correct) plug on the handle of the XL1s, where the onboard mic goes? Should it be on "mic" or "audio 1"?

Mic.

Josh...

I've made it a habit to wear headphones and monitor the camera during any shoot that requires sound. I've discovered (asw you have) that there's too much which can go wrong between the input and the actual audio circuit.

For me it's the equivalent of using a viewfinder to frame a shot. Even if I have a soundman monitoring at the mixer I still wear headphones to make certain I'm not getting any kind of distortion on the camera.

Dean Sensui
Base Two Production