7D vs zoom H4 and H4n sync test

Thanks very much Luis. I'll repeat my test tonight and post the results.

No problem - probably good for me to know my audio is going to sync up anyhow.
I'm glad this thread pushed me into testing it out properly.
:thumbsup:


EDITED TO ADD:
Buy the way, I changed the title of this thread to reflect that it's also covering H4n audio sync... didn't want anyone getting confused, and saw no need to start a new thread for it specifically.
 
Hey Luis, if you have time can you do a test with your H4n vs the computer?
I'm interested to know.

I will be checking my H4 vs 7D vs computer tonight.
 
I'll see if I can - probably won't be able to get to it right now...
as it is I shouldn't have taken the time to do that last test....
Seeing as I have actual work to do that I've been actively avoiding all day.
:)
 
My 5D Mark 2 experience... (yes, I know this is the 7D forum)

I have just synced two shoots/sets of interviews. Some are ten minute clips and once I used this method - no sync drift (thanks Matt from McGee Digital Media). Shot w/Canon 5D Mark 2 and Zoom H4n. The key is to have the video clips/sequence be actual 30 frames not 29.97 for the 5D Mark 2.

I take original clips and transcode to ProRes/30fps and create a new FCP sequence based on ProRes /30fps. Add audio clips, use PluralEyes and rock and roll.

My understanding is that the 7D should sync with no problems and no 99.9% time change since it is based on 29.97 like the H4N (but I do not have one, so I can't say). I know this is for the 5D but thought it would help:
http://brucesharpe.blogspot.com/2009/06/dslr-dual-system-audio-999-solution.html
 
JD, if you want to get the most test accuracy maybe try something like this instead of the handclap:

photo_classnotes_balls.jpg


...or a digital watch/alarm clock that deeps repeatedly when the alarm goes off or something - a periodic sound source will let you make very accurate calculations about the frequency drift.
 
Thanks very much Luis. I'll repeat my test tonight and post the results.

I'll be very curious to hear your results. I did an interview yesterday. I started off shooting 720p at 60fps, but then switched to 1080p at 29.97fps. I've since converted the 720p footage to 29.97fps.

Neither the converted 720p or the 1080p line up with my H4n. It's definitely out of sync.

I have no idea what I'm doing wrong.
 
Well, I'm feeling a little relieved. I followed Luis' example. Set up my 7D to shoot 1920x1080 @ 29.97fps. Turned the camera on ... turned the Zoom on ... and started clapping.

Dropped the H.264 QT file & WAV file into FCP. Lined up the first clap. Sure enough, by the one minute mark it was very obviously out of sync.

So, I brought the files into Premiere Pro CS4 (I never, ever use Premiere). Lined up the first clap. After two minutes the 7D & Zoom were still perfectly in sync.

What the heck?!?!?! I think I know enough about FCP & sequence settings to rule out user error, but perhaps I'm missing something?
 
LOL! I'm not sure if FCP reads .wav metadata correctly. Tell us more about what went wrong in FCP, like which sound source was faster (camera or H4n) and by how much - need some numbers to diagnose what's going onhere.

I thank my lucky stars on a regular basis that I'm an Adobe guy. I've worked with both FCP and Avid but don't really like the design of either application. Maybe it's because I came to all these editing packages from a computing background rather than getting into computers because of photography, but I find the Adobe stuff way more reliable and well-designed, on the whole.
 
LOL! I'm not sure if FCP reads .wav metadata correctly. Tell us more about what went wrong in FCP, like which sound source was faster (camera or H4n) and by how much - need some numbers to diagnose what's going onhere.

I thank my lucky stars on a regular basis that I'm an Adobe guy. I've worked with both FCP and Avid but don't really like the design of either application. Maybe it's because I came to all these editing packages from a computing background rather than getting into computers because of photography, but I find the Adobe stuff way more reliable and well-designed, on the whole.

Glad you find this amusing!

The Zoom gets slower (or the 7D gets faster???). I can't figure out how to adjust the speed so that it lines up. I've tried reducing the WAV to 99.9, but that doesn't do it. I've tried 99.8, 99.96, 99.99. I can get it in sync.

I'm going to bring the interview I shot yesterday into Premiere. Currently in FCP it's totally out of whack.
 
Wow. All I did was export my interview out of FCP as a XML. Opened the XML in Premiere. It's in sync.

Craziness!

I'm breathing a sigh of relief. I thought I was going to have to toss my Zoom. I'd much rather toss FCP. Heck, I use After Effects enough. I should convert to Premiere!
 
I just checked my test results and confirmed that the Zoom H4 (not the Zoom H4n) is out of sync with the 7D. Stretch on audio would need to be 99.9%

Interestingly enough I checked the third recording I had which was made on the laptop at 44.1khz using sound studio. When I dropped that into the same (23.987) timeline it came up 6 frames short! Go figure. Moral of the story is always test and know your equipment. Thanks once again Luis for your contributions.
 
I have the same problem as Finster:

Shot in 1080p25p recoreded on the H4n in 4Ch mode 48kHz/16 bit
Brought everything into FC timeline, synced up with the clap.
After 10 minutes the video is 18 frames behind.

No additional speed changes or anyhting applied.

Anyways, anyone have a solution for that?
Slowing down the audio to 99,89% does the trick for me, but how come some people have problems with that, others don't?
I'm really confused now...

Max.

--

Additional notes:

I also brought the very same clips into Premiere CS3, synced with the clap and it works perfectly... ?!
So it isn't the h4n, is it?
 
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I'm no audio guy, but since the 5d/7d records 44khz and we're setting our Zoom's to 48khz, won't that come into play?
 
Finster, you will be happy to read this, I think I solved the problem: It's some rather odd import system, but it actually makes sense... ;)

http://forums.creativecow.net/thread/8/1044917

You have to delete the files out of the project, set up FCP for the proper easy setup, 29.97 if that's what you need. Then quit fcp, then relauch your project, then import the wav file.
This did the trick for me, now no speed stretch is required for FinalCut when importing your H4n files PLUS your system is set up properly ;)

Now I am happy at last and lost over half a day just on that. :)

Best,
Max.
 
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Finster, you will be happy to read this, I think I solved the problem: It's some rather odd import system, but it actually makes sense... ;)

http://forums.creativecow.net/thread/8/1044917

This did the trick for me, now no speed stretch is required for FinalCut when importing your H4n files PLUS your system is set up properly ;)

Now I am happy at last and lost over half a day just on that. :)

Best,
Max.


Thanks for this info, this also goes for 1d MRK IV files. I thought I had come across some strange 1d mrkIV issue, with it not syncing to my h4n files, but the easy setup did the trick. Any 25p setup as a start will do it! Thanks again for this, saves me alot of work next week on location :)
 
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