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-   -   Major problem with my HD100 (https://www.dvinfo.net/forum/jvc-gy-hd-series-camera-systems/60644-major-problem-my-hd100.html)

Tom Valens February 14th, 2006 01:13 AM

Major problem with my HD100
 
I've just encountered a major problem with my HD100 while filming a long documentary (shooting in DV), and am trying to figure out what happened. I've been shooting between 3 and 4 hours a day (I'm up to hour 107 so far), and today a good half of what I shot doesn't have timecode or audio. The video appears fine, and while I was shooting I heard the audio fine, it registered on the viewfinder meters, and the timecode kept marching along as usual. The first roll I filmed today, beginning half way through from the previous day's footage, was fine. The second roll was fine for the first 4 minutes, but the entire rest of the tape had no sound or timecode when played back (it seemed fine at the time I filmed it). The third roll also had no audio or timecode for the first 33 minutes, but then the audio appeared for the rest of the tape, and the timecode showed up (beginning at the "correct" timecode of 33 minutes, not 0). The fourth tape was fine.

So, I had this one big chunck, from near the beginning of the second roll to the middle of the third roll, with no audio or timecode. I had had this problem one time before, about 17 rolls earlier, but it had lasted only one shot, and I assumed it was something that had gotten onto the audio portion of the head. (I have been using cleaning tape regularly, every 20 rolls or so)

Does anyone have any idea what's happening? I plan on calling my reseller tomorrow, but I suspect they won't know anything about it. Does anyone know of a JVC tech contact I could call to try to find out what's wrong?

Thanks for any help. Tomorrow I'll go back to filming with my PD150, but I'd sure like to use the JVC again as soon as possible (rigging two wireless mike receivers and a mini mixer onto the PD150 is a drag).

Tom Valens
Tamalpais Productions
Forest Knolls, CA

Tim Dashwood February 14th, 2006 04:26 AM

Did you try cleaning the heads? How often do you normally clean the heads? Every 10 tapes, 20 tapes, etc?

Diogo Athouguia February 14th, 2006 06:34 AM

My camera was having breaks on TC and audio after pressing REC. I was sent a firmware update for the camera's VTR and the problem is now fixed. I don't know if it has anything to do with your situation, but you can tell my story to JVC tech and ask for an update.

Jiri Bakala February 14th, 2006 08:48 AM

Let us know you firmware version, please.

Diogo Athouguia February 14th, 2006 09:40 AM

The VTR CPU firmware is listed as C1594 V0114.

Tom Valens February 14th, 2006 10:18 AM

Tim, I use a cleaning tape about every 20 rolls. Maybe I need to do it more often?

A few more details: I've used only new Sony Digital Master tapes in this camera. I've heard various opinions about which tape to use, but when I asked several JVC tech types at trade shows they said I shouldn't have any problem with the Sony tapes, as long as I didn't keep switching brands.

Another thing I thought of after I posted yesterday. I remember when filming at about the point where the timecode/audio drops out, that the timecode would keep resetting to 0 at each new shot. Timecode was set at Regen. This should have been a warning, but at the time (hectic filming) I just reset TC to Record Run and continued filming, with the timecode showing as I would have expected. It now seems to me that in my situation, at very least, I should keep the TC at the Regen position - so I can have a warning that if the TC resets to 0, I may well not be recording any timecode or audio (since there's no TC recorded, each new shot resets to the current timecode, in this case 0).

Does this make sense? In DV recording, are the timecode and audio recorded at the same part of the head, and separate from the video? If so, the most likely explanation I can think of is dirty heads, and I should be leaving the TC setting at Regen and using a cleaning tape more often.

Daniel Epstein February 14th, 2006 10:27 AM

Tom,
Have you tried to play the tapes on another machine? This sounds like a tape tension or alignment error has crept into the camera.

Brian Chow February 14th, 2006 11:28 AM

audio fixed
 
I too have had that problem, actually ruined a couple of interviews that I can't re-shoot. I contacted JVC Canada and they actually replaced my camera. The new one works beautiful. Hope this helps. I don't know anything about firmware or anything.

Brian

Gary McClurg February 14th, 2006 01:27 PM

I might have to buy the camera for an upcoming shoot... what is the latest firmware update....

Thanks Gayr

Tim Dashwood February 14th, 2006 04:43 PM

Quote:

Originally Posted by Tom Valens
In DV recording, are the timecode and audio recorded at the same part of the head, and separate from the video? If so, the most likely explanation I can think of is dirty heads, and I should be leaving the TC setting at Regen and using a cleaning tape more often.

In DV mode there is a separate PCM audio track, and possibly a separate head. I doubt you would have this problem in HDV mode because the compressed audio is part of the main compressed stream. Therefore, in HDV it would be all or nothing.

Tom Valens February 18th, 2006 08:07 PM

This is an update to the problem with my HD100.

I had assumed that the missing audio/timecode was likely somehow related to problems of dirty heads. However, I later learned this was highly unlikely, since anything on the heads (whether in DV or HDV mode) would have affected the video image as well (which was fine throughout). I've since talked with JVC Service Department people in Cypress, CA, and found out that it is most likely a software glitch - occasionally pressing the video Stop button sends the wrong signal somehow. The camera is currently being shipped to them for an update. They seemed to recognize the problem and were pretty confident that this would solve it.

Hopefully this is a relatively isolated problem, but I just thought others should be on the lookout just in case. I had shot about 70 hours of material with the HD100 (all in DV mode, except for a few HDV tests) before the problem first appeared. The first time, just a single 2 minute shot had the missing audio/TC. But then, about 15 tapes later, I lost them on almost an hour and a half, spanning two tapes (so the problem persisted despite the changing and reloading of a new tape). About 10 tapes later it happened again. I had hoped that by keeping the timecode switch in the camera set to Regen that I would be able to catch it if it happened again (thinking if there was no TC, it would reset to 0), but even then the timecode in the viewfinder while shooting just kept marching along as usual. Using the RET button on the lens would have been a good way of checking that I had recorded sound, but on a verite documentary where I'm shooting 3 to 4 hours a day that's not very practical.

Albert Henson February 19th, 2006 12:41 AM

Thanks for the update. I had a similar issue with the camera, where my audio sounded fine throught the headphones plugged into the camera , but when I played back the video the audio was hot. Since then I pad my mic. to air on the side of caution. I doubt that yours is completely isolated as an issue. It just seems to be another issue with early adopters of the camera. oh well, I'm glad jvc is aware of the issues so that future revisions can be improved upon. Again thanks for the update. I'm certain other users will find your info useful.

Paul Moss February 21st, 2006 05:32 AM

No Timecode on tape ...me too.....!
 
Hey Tom,
Half way through a one hour TV special here in Oz. The editor came out to location today to tell me that on the 4th tape of 8 so far, there is no TC at all through the whole tape.....!! Audio is there and the picture is fine, but no TC. Using the JVC PRO HD stock, tha camera had a head clean at the start of the shoot...?
I hope your info about a firmware update fix is correct. There are a lot of unhappy crew on my case right now, questioning wether we should still keep shooting on this camera.....?

Sam Hancock March 4th, 2006 10:16 PM

New Info?
 
I am having this audio/timecode dropout issue as well and was just wondering if Tom or Paul have a final word on whether it's simply a firmware problem?

Tom Valens March 5th, 2006 02:03 PM

I've posted an update on another thread here (see "Mode Changing" - my entry was on Feb 27). It seems like the firmware change on my camera was to the VTR CPU. So far I've shot an additional 20 hours or so without a problem - but I'm still a bit apprehensive, and use the RET button to check footage much more now than I used to. But so far, so good.


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