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-   -   HELP! Video Tape Footage Recovery (https://www.dvinfo.net/forum/canon-xh-series-hdv-camcorders/235462-help-video-tape-footage-recovery.html)

Nancy Rock May 16th, 2009 07:05 AM

HELP! Video Tape Footage Recovery
 
I recently traveled to Mexicali, Mexico over Spring Break to build a church and to work with underprivileged kids. I filmed the entire thing on a Canon XH A1 HD camcorder using Sony HDVM63 tapes.

When I got back, I was able to play back all of the tapes. But when I went to upload the footage to my computer, one of the tapes would not play back. I could see the footage when I fast-forwarded or rewound it, but when I pressed play, the screen would go blue and the time code would not appear.

I checked all the settings to make sure that I was playing it back in the same way I had recorded it. I even tried the tape in a several other camcorders, including a different Canon XH A1, but had no luck.

I sent the tape into Sony Media Services. They informed me that they could not fix it. They didn't know what was wrong with it, and they could not fix it. I talked to Canon and they could not help me either.

I spent the next two weeks talking to countless engineers, editors, techies, etc... trying to find a way to recover the footage. No one knew what was wrong with the tape and no one had the equipment to fix it.

I decided to go all the way to the top. I e-mailed Howard Stringer and told him all about the defective tape. He had a man named Tom call to tell me that it was not their responsibility and that they could not help me.

I have tried every out of the box method I could think of just short of tampering with the heads on the camcorder, which I am not willing to do since the camcorder itself is brand new. The footage on the tape is irreplaceable and it holds so much meaning for me and the group I went with. The thought of losing it forever is unbearable.

I would be very grateful if someone were able to help find a solution to my problem. Please let me know if you have any questions. Thank you.
Kyle Rock
membarock@yahoo.com

Bill Pryor May 16th, 2009 02:38 PM

Being able to see the image when you fast shuttle but not in normal playback is a classic symptom of a head alignment issue. But if a camera's heads are out of alignment, it will most always play back the tape it recorded. What usually happens is that the tape won't play back on anybody else's deck.

The only thing I can think of to try is take one or two of your good tapes and see if they play back OK on somebody else's camera or deck. That would rule out a head alignment issue. Also, record something new on a new tape and play it back on a different camera, just to really be sure there's no problem with your camera.

If the tape was recorded at an extended playback setting, then it wouldn't play on anything unless you switched that camera's setting too. Are you certain that's not the problem? Or maybe it was recorded in SD instead of HDV and all the cameras you tried it on were set to HDV?

I think it has to be something in the way the recording was made, whether an alignment problem or something else. Was this the last tape you shot? If so, that would make me think head alignment. But on the other hand, if suddenly the heads went out of alignement, they wouldn't play back the other tapes. Wow, this is really weird. I'm just thinking aloud here...I don't see really how it could be head alignment, but double check that anyway. And try turning off HDV playback and check that again. The symptoms, in my experience, say head alignment or slow recording speed. I don't know what else it could be. When you were shooting, did you spot check any shots on that tape, or bars at the head or tail?

Chris Soucy May 16th, 2009 03:37 PM

Hi Nancy..........
 
Like Bill, I've seen this pop up on DVinfo with monotonous regularity, and every time I've tried to think of a way out of it, walked straight into the wall Bill did.

I too thought it was an alignment issue, but am now not so sure, it doesn't fit with one tape out of a batch, nor with played once but not a second time.

The "visible in FF" I put down to "reading key frames but can't build a frame stream from the GOP for some reason".

Given that latter thought, I wonder if there is some kind of "header" written every time you press "REC" that is required to build a frame stream from the key frames and following data.

If so, and it got corrupted, for whatever reason, that take would not be decipherable.

But what about the next? And the next? Etc, etc.

This is the longest of long shots based on pure guesswork, but it might just have some merit.

Run a cleaning tape through the original shooting camera, at least twice.

Put the faulty tape in and rewind to the beginning. Press play and let it run right to the end.

Any takes?

Rewind it to half way.

Remove tape and power down camera.

Power it back up and load a "good" tape". Play for 10 seconds.

Remove and reinsert "bad" tape. Play.

Any takes?

(This is always assuming it doesn't contain one take on the entire 60 minute tape - that would be a bummer).

Nothing to lose here but an hour or two.

(The reason for the intermediate power down is it is possible that a corrupted header somehow isn't flushed from the processor buffers even when a good header is read, thus, once corrupted, the entire tape becomes unreadable. Hey, I'm guessing here!)


CS

Robin Miller May 16th, 2009 04:09 PM

Another "help" - identical problem, except...
 
...it's a tape I used to record a series of takes, then successfully captured those clips to my computer. A couple of days later I had a short shoot, that tape was still in the XH-A1, so I did my basic "end search" and started shooting from there.

After the second shoot, I get the "see the image flashing by when I press play + FF thing," but see nothing on "play." Now I can't even play the first half of the tape, which I already captured.

I tried recording a few seconds at the start of the tape, over what was already there. No problem. Plays back fine -- but stops and blue-screens at the end of that clip.

Head cleaner? Check. Did ti.

Shot other tapes and played/captured them since? Yep, no problem.

Tried the bad tape in a friend's Canon HV-20, since I only have the one Canon? Check. But no joy - and we know she can play my XH-A1 tapes because she's used her HV-20 as a deck for my XH-A1 tapes a couple of times when we were doing "shoot and edit NOW" jobs.

Time code? Dunno. Could be. I may send this tape to Pacific Video Repair and see what, if anything, they can do. They fixed a physically damaged tape for me once before; service was as promised and the price was decent. Just emailed their customer service dept; will relay what they say.

Chris Soucy May 16th, 2009 04:51 PM

Re - boot.............
 
Having posted my above missive, a spot of household shopping gave my brain time to go into "idle mode" and give this some more thought.

It occured to me that the data on the tape is encoded HDV (duh!).

What you see on the camera lcd during playback is decoded HD (or not, as the case may be).

The o/p of the Firewire port is encoded HDV straight off the tape, isn't it?

So, what's the Firewire stream look like when you've got the BSOD on the camera lcd?

Can your/ my/ someones NLE make sense of it even if the camera processor can't?

The more I think about this the more the chasm of ignorance yawns before me.


CS

PS: BSOD = Blue Screen Of Death (very popular Windows desktop)

Robin Miller May 16th, 2009 05:25 PM

"So, what's the Firewire stream look like when you've got the BSOD on the camera lcd?"

In Sony Vegas, like it's stuck on the last complete frame. In other words, nada.


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