Audio recorder that will sync up with video

[Jeff Harper]

Does the H1 recorder sync up perfectly with video? How do I know which recorders will do so? I currently use an older Olympus model that does a decent job, but it will not sync up without adjustments.

I use recorders primarily at wedding ceremonies placed on the lecturn to capture readers, etc. and occasionally for toasts.

I have been told the recording mode I choose will affect how the audio will sync up no matter which recorder I use, is this correct?

[Bill Grant]

Jeff,
I use 3 H1s I generally place them about 20 mins before the ceremony. in post, I run puraleyes, it synchs and i do nothing else. works great.
Bill

[Jeff Harper]

Thanks Bill, great to know plural eyes works with the files, I had no idea.

[Steve House]

Originally Posted by Jeff Harper

Does the H1 recorder sync up perfectly with video? How do I know which recorders will do so? I currently use an older Olympus model that does a decent job, but it will not sync up without adjustments.

I use recorders primarily at wedding ceremonies placed on the lecturn to capture readers, etc. and occasionally for toasts.

I have been told the recording mode I choose will affect how the audio will sync up no matter which recorder I use, is this correct?

No recorder will sync perfectly to video unless both camera and recorder clocks are driven by a common time-base generator sending Wordclock to the recorder and genlock to the camera or have a recorder that will receive and sync to blackburst from the camera. The difference between various recorders lies in how long you can go before drift takes you out of sync - inexpensive consumer recorders might drift out (in some cases) in a matter of minutes while fully professional recorders might give you several hours before it gets objectionably far off. Part of the price difference between, say, a Zoom and a Sound Devices lies in the engineering of the circuits and the quality of the components used. You get what you pay for. The cheapest consumer recorders can be so marginal that there will be significant variation between one unit and the next one in line coming off the assembly line. Such speed variations are of no consequence in a mini-recorder used for classroom notes, etc, but a disaster, or at least a PITA, when you try to use the recorder for sync audio.

Variable bit rate and compressed recording modes like WMA or MP3 can have a seriously negative effect on the stability of the sync. Don't even THINK of recording in any mode other than uncompressed WAV (PCM), 48kHz, at least 16 or 24 bit (though the relatively low quality of other components in the audio chain make 24 bit silly overkill on most small consumer recorders). The only possible exception to that is the FLAC lossless compression offered on some recorders. Formats like MP3 are distribution formats, never intended for master recordings.

[Peter Riding]

I use three H1's and one H4n together with up to three camcorders and two 5DII's and sync them using Pluraleyes in Vegas Pro. I have the Zooms on 16bit 48KHZ WAV. I don't have any drift issues what so ever. The longest continuous recordings tend to be up to an hour but in fairness most are more like 20-30 minutes. So I'd say you are safe with weddings. Even where the ceremony is very long -the longest I've done recently was two hours eight minutes - you still more than likely have the opportunity to stop and restart the various recorders part way through if that makes you feel more comfortable.

Of course if you have a recorder running for an excessively long time but only need a small segment of it e.g. A reading then you could simply chop off the start and the end and export your resulting edit. I often have recorders running long before the start of speeches as a precaution and then use the free editor Audacity to make a keeper of the part tat I need. Loads of program's can do that as you know.

Pete

[Jeff Harper]

Steve, Peter, thanks.

Peter, I'm really glad to have ordered the zoom a few minutes ago. Thanks for mentioning your setting.

What sized card is good for, say 4 hours of recording at the setting you use? I'm thinking 8Gb might be perfect.

[Bill Grant]

8 Gb I get 6:30 or so. You tend to get lazy with offloading the more you have on the card. :) I also have never found a drift issue on the H1 or H4n over 3 or 4 hours of workshops or receptions. Consumer or not, they tend to work great.
Bill

[Jeff Harper]

Bill, thanks much. I've got it covered with my 16GB cards. Nevertheless, I will will get a dedicated 8GB just to save the wear and tear on my fancy 16GB 30mbps cards.

[Peter Riding]

I use 8gb in all my cards. The H1 does come with a much smaller card, I can't recall what size.

I think the H1 with 8gb is good for about 11 hours at 16 bit / 48 kHz but it does tell you on the display. The reason I like the big cards (they don't need to be high performance) is that they are microSD so difficult to handle plus the card door is fragile; so I just leave the cards in there all the time and download direct from the devices. I have the card doors sealed with sticky velcro furry side up :- )

Also big cards are good for those occasions when you start the recording too early, maybe accidentally, as you know that the capacity will still be fine subject to a battery change.

Pete

[Jeff Harper]

Thank for your post Peter. Between the recorder and PluralEyes what a blessing! Technology is just removing so many barriers. Not long ago there were no inexpensive recorders that would so closely match video tracks, at least that I knew of. Now for $100 we have these.

I will order an 8GB card for the H1, thanks Peter.

[Steven Reid]

Jeff, I don't use a Zoom (I have a Korg MR-1000, from which I downsample to 192kHz/32-bit floating), but on long recordings, say, 30 minute files, I might notice audio drift of about 1-2 frames on my NLE timeline. It could be my particular combo of video and audio; the drift is barely noticeable, but there.

On the timeline, I find it convenient to pick a few spots in the audio event and split it at a few points, for instance during silence or audience applause. Then let PluralEyes go to work. In the synchronized result, the splits mentioned above will usually reveal just the slightest overlap to account for the drift, with the overall result being perfectly synched audio and video. Otherwise, the choice for PluraEyes is sync the beginning or end, the one being 1-2 frames off.

-Steve

[Jeff Harper]

Steven, as Steve H points out, separately recorded audio won't be perfect, but your method sounds like the best way to get things synced up nearly flawlessly, and perfectly fine for my purposes. Great tip, very simple, practical way to tighten things up. Thanks a bunch for your tip, Steven.

[Steve House]

Originally Posted by Steven Reid

Jeff, I don't use a Zoom (I have a Korg MR-1000, from which I downsample to 192kHz/32-bit floating), but on long recordings, say, 30 minute files, I might notice audio drift of about 1-2 frames on my NLE timeline. It could be my particular combo of video and audio; the drift is barely noticeable, but there.

On the timeline, I find it convenient to pick a few spots in the audio event and split it at a few points, for instance during silence or audience applause. Then let PluralEyes go to work. In the synchronized result, the splits mentioned above will usually reveal just the slightest overlap to account for the drift, with the overall result being perfectly synched audio and video. Otherwise, the choice for PluraEyes is sync the beginning or end, the one being 1-2 frames off.

-Steve

1-2 frames accuracy may, or may not, be good enough. Typical broadcast standards, such as PBS's Technical Specifications, state that at no point may the audio lag or lead the video by more than 1/2 frame.

[Jeff Harper]

Steve, sadly, my wedding videos are not shown on broadcast TV. Hopefully the audio from the H1 will be easy enough to sync that my customers will not see much of a lag. Using Steven's method of chopping things up a bit, I'm hoping things will be fine for my wedding videos.

The video files from my GH2s and XA10s also do not meet broadcast standards, so I guess there is synchronicity of some sort here.

[Steven Reid]

Originally Posted by Steve House

1-2 frames accuracy may, or may not, be good enough. Typical broadcast standards, such as PBS's Technical Specifications, state that at no point may the audio lag or lead the video by more than 1/2 frame.

Well, good enough for this home-brewed videographer. ;) I thought it was plain as day that my suggestion was tantamount to a workaround hack in post. I certainly appreciate that the pros on this forum have to follow much higher standards during production, such as the one you mentioned.

Cheers,
Steve