Sound "lagging"

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Permalink Reply by Bill Mecca on October 5, 2009 at 2:02pm

The digital clocks are different between the miniDV and the CD, You've pretty much state the two ways around it. You might be able to "fit to fill" the audio to the video, but it would probably change the pitch.

I'd be happy to hear any other solutions.

I don't know of any other than to record the audio directly to Mini DV with the video, which most don't like to do, for various reasons, but it would solve the synch problem. That would work with a feed from the board, but you need a sound guy who knows his stuff, and everything has to go thru the board. Playing in a bar band myself, the only things we send thru the board are vocals and my sax. Other option is to mic the room and feed that directly to the camcorder as well. (also gets some crowd noise, which a board feed would not.)

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Permalink Reply by Nishi on October 5, 2009 at 2:19pm

Hi Bill, thanks for your response. We've been using the camera mics to record the room tone and mixing it in at appropriate moments (cheering, crowd singing along, etc.). We've had some unpredictable results getting live feeds from sound boards (weird distortion etc.) so now I'm paranoid going that route lol.

While we're on the subject of recording bands, what legal precautions do you take when shooting at a bar? Do you post a sign somewhere in the venue that says "You might be videotaped... etc." and is this enough to get away with getting some audience shots in without having to get people to sign appearance releases?

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Permalink Reply by Earl Chessher on October 5, 2009 at 2:28pm

Nishi - in desperation I once stupidly (well, maybe not stupid because it worked well enough) recorded from CD player output into Canon camera audio input, making a MiniDV copy of the CD audio. It worked to a great degree, with no drift apparent over a half-hour. I suspect longer times my revisit the problem.

Your bothersome workaround, as Bill has indicated, is perhaps the most accurate solution, but like I said on Twitter I have read somewhere. in passing, of software solutions that can correct drift like that, or delay, and some have claimed no discernible change in pitch. I regret that I do not remember specifically where I read/heard. I suspect Jay might be the resource man here. Sure wanted to be your hero :-) maybe next time.

I post signs, commercial (other) videotaping session in progress, your presence here during this session indicates your acceptance of your possible inclusion in the resulting production intended for commercial and/or major distribution...

I believe prominently displayed and ample posting of them (though not a total guarantee) should be legally sufficient. I've often also had an assistant with clipboard and simple release forms placed next to a sign encouraging people attending during the video session stop by and sign a release or leave the premises for (an estimated length of time) the duration of the production - apologizing, of course, for the inconvenience it may cause them.

I think you've read my thoughts regarding taking chances on direct connects to house sound - I've replaced too many blown camera audio circuits, or lost sound, or been cut out too many times to be comfortable at all with anything beyond my own devices. I do use a number of Zoom H2 standalone digital recording devices for audio backup in these and other situations with great results and very little drift, if any over hour-long segments.

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Permalink Reply by Bill Mecca on October 5, 2009 at 2:39pm

Nishi,

yes bar bands have notoriously band sound since most times they run it themselves instead of hiring a sound tech, even if they do, many times they are just a hanger on, and even if they are good, most bars do not have a proper place for FOH (front of house) sound, so the tech is off to the side. that makes it difficult for them to make adjustments. they have to tweak something, walk out front, listen, walk back and tweak again. Distortion etc from the soundboard is usually a mismtach of mic/line or dirty unused connections being used for the first time ever.LOL or they have cables crossed with electrical wires etc. It is unpredictable. Best practice would be to control as much of it as you can yourself, i.e. setting up your own multiple mikes, mixing and recording onto Mini DV with a back up to CD etc.

years ago I had a guy tape a band for me in Boston for a project that never happened, but he just used the onboard mics and the sound was what it was. We got the same thing the crowd heard, so it was an accurate representation of their sound. I don't really do muchc work for hire these days, but was going to do a demo dvd for the band I am now playing with (before I was) but it was going to be a montage of clips with their demo CD as the soundtrack, not worrying about synch.

Nishi said:

Hi Bill, thanks for your response. We've been using the camera mics to record the room tone and mixing it in at appropriate moments (cheering, crowd singing along, etc.). We've had some unpredictable results getting live feeds from sound boards (weird distortion etc.) so now I'm paranoid going that route lol.

While we're on the subject of recording bands, what legal precautions do you take when shooting at a bar? Do you post a sign somewhere in the venue that says "You might be videotaped... etc." and is this enough to get away with getting some audience shots in without having to get people to sign appearance releases?

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Permalink Reply by Nishi on October 5, 2009 at 3:59pm

Thanks Bill and Earl, I'm glad I'm not the only one who's encountered this. Thanks for all of your suggestions. You've helped immensely.

Earl - you will always be my hero. Now where is that Jay-Bat Signal? hahaha!

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Permalink Reply by Jay Michael on October 5, 2009 at 11:53pm

The first thing I would check is to see if you had any dropped frames when you imported the video into the computer from MiniDV. These dropped frames could be the culprit causing the video to fall out of sync. You can try re-importing the video and get a better transfer with no dropped frames. Not sure if your NLE will show you if it dropped frames or not.

Bill is also right about miniDV and cd being different and yes there can be a slight pitch change that could cause the misalignment. Or even bytes lost during recording.

Here is something you can do to fix it:

Locate a point just before you notice the audio is out of sync and place a cut there. Do not separate the cut files. The cut will be unnoticeable if you don't move the clip on the timeline.

Now select the second part of the clip, the part that is out of sync.Your NLE should have a speed control, locate it and put in a slight "speed up", say about .05. Then watch the clip. See if it is now closer to sync. You may have to play with the numbers until you get it to fall back in sync. {The "speed up" I'm talking about here is the same control you use to do a slow motion or speed up the clip.}

If you need to back the video up to get it into sync you may be able to put a slight dissolve between where you cut the clip. In VPX you just back the clip up slightly over the previous clip at the cut point, VPX will do a dissolve there. Not sure how your NLE does a dissolve but you get the idea. Just back the clip up slightly over the front part where you cut it. If it is only a slight dissolve you probably won't notice it unless you look for it.

Either way you should be able to get it to fall back in sync. Backing it up or advancing the speed slightly to get it to stretch out to fit the audio. Once you get it into sync group or lock the audio and video together so you don't knock it back out again. ;-)

Hope that helped! ;-)
J.

~~
Nishi said:

Thanks Bill and Earl, I'm glad I'm not the only one who's encountered this. Thanks for all of your suggestions. You've helped immensely.

Earl - you will always be my hero. Now where is that Jay-Bat Signal? hahaha!

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Permalink Reply by Bob Kessler on October 6, 2009 at 12:23pm

Bill hit the nail on the head when it comes to recording live musicians. Even in the best of circumstances (back when I was a performer with a prominent oldies band) in venues like The Apollo, Carnegie Hall, etc. where you are performing with fantastic equipment the FOH mixer is mixing for the room. On those occasions when we were performing for broadcast all of the signals were "split"; each individual instrument/voice was sent to a separate remote mixing system.

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Permalink Reply by Pierre Samuel Rioux on October 7, 2009 at 1:41am

You lost the sync, it's possible the other ( cd recorder ) is battery power go down, or the camcorder tape is more hard to turn, or the camcorder battery going down. When i shoot a event at the end of the 1hrs tape i change the tape and the battery in the camcorder.( or used a ac converter )
You could also lost the sync in a situation where the sound recorder is close and the camera is far a way the distance could ad a delay in the image and again lost the sync.( more a outside show )

You have Chrystal motor those motor are running in a steady speed, you have wild motor after a period you lost the sync like the old tape recorder.

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Permalink Reply by Nishi on October 8, 2009 at 11:12am

Thanks, Jay, Bob and Pierre. I've learned a lot from you all.

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Permalink Reply by David Steeves on October 12, 2010 at 11:14am

While we're on the subject of recording bands, what legal precautions do you take when shooting at a bar? Do you post a sign somewhere in the venue that says "You might be videotaped... etc." and is this enough to get away with getting some audience shots in without having to get people to sign appearance releases?


there is a reasonable expectation for the audience being in public to be filmed, that what the law says, if there is someone famious in the audience, that make a living with there face, thats a different story
DAve

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