Re: Recomended Mic Placement for Orchestra Recording
 

Video travels at the speed of light, audio at roughly 1000 feet per second. So if the camcorder is 100 feet from the stage, the audio lags video by 3 frames.

The human brain understands this if the image conveys the distance to the sound source.. However, if the audio leads the video it will seem unnatural.

Re: Recomended Mic Placement for Orchestra Recording
 

It is noticeable otherwise he wouldn’t be going to the trouble of sending the audio to the rear cameras.

Re: Recomended Mic Placement for Orchestra Recording
 

Yes, the lag is noticeable. Particularly when you're showing a tight close-up of a pianist's fingers on the keys. Without the perception of distance in a tight shot 3 - 4 frames is a problem. At least it's a problem for me!

And by the way, Paul, no problem I know you were well motivated. I'm too old to take anything personally.

Re: Recomended Mic Placement for Orchestra Recording
 

The other problem I’ve run into occasionally is that in a noisy or reverberant environment, sometimes the post sync softward can’t resolve the two audio sources. Ouch! If your nice direct sound recording is too different from the camera sound recording there can be trouble.

I wouldn’t think that a problem in a concert hall... but it is worth bearing in mind. For our automatic sync digital magic to happen there needs to be some substantial similarity between the two recordings.

Risking bad sync can have big consequences. For long-form performances in a single take it’s not so bad to manually do a sync or two, though it is yet another skill to develop. If you have to do 10 or more it can get bad!

Another potential gotcha’: Always always all devices should be recording at a standard 48KHz sample rate. If you have an audio recorder capable of 96KHz such as Jim’s that works too. Some cameras and many recorders allow 44.1 or even 32KHz sample rates - using them (even for reference tracks) can greatly complicate post-sync, depending on the software.

Re: Recomended Mic Placement for Orchestra Recording
 

The point I made badly is that if you have to sync the camera to the real audio, then even if you feed a cable, you still have to slip the video against the record sound, so the room sound gets you to roughly the right place, and then moving them into sync has to be done whatever, so the few frames is surely irrelevant? I don't use any clever software to sync my theatre stuff, ever. There are always visual clues. The delay from the house PA to the audiences ears is so short in a theatre, up to the balcony that it can be ignored. In a stadium it's significant, but a recording that far away would sound terrible anyway.

Re: Recomended Mic Placement for Orchestra Recording
 

I use PluralEyes and it's worked quite well for me. I've had as many as 8 cameras running so I'll gladly use any automation that works.

Re: Recomended Mic Placement for Orchestra Recording
 

While using a digital 2.4gHz wireless should get a much cleaner and less delayed signal for sync than just using the balcony camera's local mics, remember there is some amount of delay in the digital processing of the new wireless mic systems. It might be less than a frame, but it's easy to test out and find exactly what this amount is. That way if something seems slightly delayed even with a wireless connection, you'd know what it was coming from.

Re: Recomended Mic Placement for Orchestra Recording
 

Yes, you're absolutely correct - there is still a few millisecond delay. The System 10 latency is spec'd at 3.8ms.which would be roughly 1/10 frame. I can live with that. Allowing for a little more latency through the MOTU box it's probably closer to 1/5 of a frame. I can live with that as well. If they want it any better than that they can get me an assistant or two and I'll run cable. I remember one time I did have two people running cable and after it was all done it turned out the male and female ends were swapped. Which is why I carry a couple of short cables with convertible ends as gender changers.