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The reply took about a month. Because I am in Canada, they apparently won’t provide support to me.
Perhaps the support would come more quickly to a US based customer. Please keep me advised if you have any luck. Like you, I love the recorder, but it will go up for sale on ebay if I can’t get around this sync issue. Thanks Ted
Below is the response I recieved from the H4 Samson product support.
I am not convinced that it is my Camera – as I haven’t had similar sync issues with other recorders.
I will be trying some tests with a different camera.
The H4 does records in PCM linear format in real time. It sounds like the problem is with your camera and it’s drop frame time code.
Samson Technologies does not distribute nor support Zoom products outside of the U.S. For more assistance, please refer to http://www.zoom.co.jp to find your local distributor.
Samson Product Specialist
Thanks – I agree. I have contacted their support directly and will give them a chance to resolve the issue. Maybe there is a software upgrade or something…
I will post any advise they give.
Did that – see my previous post. When recording in MP3 format there is significant difference…when in Wav Format much less – around 2 seconds over 30 minutes.
The Camera was the most accurate (type sync on the digital video file exactly matched the stop watch).
The audio when loaded on either Ulead 10 or Adobe Premiere was about 2 seconds out.
Splicing out about 2 frames of audio every minute seemed to correct the problem, but is very time consuming…
I don’t have a total fix, but I found that if I cut two frames of Audio every minute – the sync was very good.
I wan’t dealing with music, so it was easy to find a relatively dead spot in the sound track. That was much easier than mucking with the video – which was my first try.
If anyone has a better fix – please post. The Zoom is such a great tool, I would hate to not be able to use it.
I tried loading the files in Adobe Premiere 6.0 – but had the same result.
My next step is to try the experiment with a different cam-corder – ie dv rather than digital8
Is there a possibility that this has something to do with 29.96fps??
I just got my H4 for I am working on my first project – which was a 3 act school play. Each act was about 30 minutes long.
I had assumed that the audio sync would be a no-brainer. I was supprised when I found that by the end of each act (30 minutes) the audio and video were out of sync. I originally recorded in mp3 format – and the audio was out by about 3 seconds at the end of 30 minutes. Based on the advice above, I converted the audio to wav. It was then much closer, but still about 1/2 second out after 30 minutes – very noticable.
As above, I solved the issue by cutting out 2 frame segments of the audio every minute or so of the video. Some hassle, but it saved the project and worked very well.
I did a test by setting up my video camera in the kitchen and running it along side the H4 and a stopwatch for 15 minutes. I tried both mp3 format and wav as recording format. I did not try different sample rates, but maybe should.
I then loaded the audio and video files into my ULEAD 10 editing program.
The timecode on the camera matched the stopwatch exactly (as close as I could tell). I made a clapping sound at the start and end of the test. In each test the sound file did not match up with the video. In each case it was about 1/2 second longer than the corresponding video. When I get a chance, I will muc with the sample rates to see if that makes a difference – both on the H4 and the Editing software..
It would be much simpler if the audio and video would sync without all of the extra work…
My trials continue to show a slight time sync difference between the digital recorder and my digital 8 camcorder.
The camera appears to be very accurate – at least camparing the timestamp and a stopwatch.
In each case my Audio is a bit longer than the video.
I took your advise can cut small sections of the audio out. This was some trouble but worked very well.
I removed two frames every minute. I was able to target relatively silent spots in the audio – so it is not noticable.
The effect seems to be consistent with each new recording. Still not sure if it is my software, the recorder or the cam…
At least I have a workaround…
Thanks Hank and Mark for the suggestions.
I made a short 12 min movie last night as a trial, but ran out of time before I had a chance to load it on the computer and put the video and wave files side by side. I used a stop watch, and clapped my hands at various time intervals. I should be able to see which component is different.
Mark – I think you may be on to something with the recording format. I used the MP3 format on the H4 Digital recorder. Today before work, I loaded the mp3 file into an audio program, and saved it as a wav file. This file matched the video much more closely, althouth not perfectly. I have a feeling that if I had used the wav format on the original recording, it would have worked better. I will do another test and let you know. I hope to have some time this weekend.
I hadn’t thought about the reduction in video quality by changing slowing it down or speeding it up slightly, but it makes sense. I do have some software that will let me do it with the audio – so that may work better. I suspect that with the very minimal change (2-3 seconds over 30 minutes – 0.2%) it should not change the pitch noticably – particularly when there is no music in this particular project. The idea of chopping out little bits of audio is also interesting. I’ll give it a try and let you know how I make out.