P2 corrupt files

[jpsheets]

I was shooting B roll this weekend on a short film, using DVCPro50 to two 4 gig cards. One card was fine, downloaded no problem, footage looks fine.

But alas, the second card had the dreaded red X through the clips. I tried to repair but of course it couldn't be fixed. Interestingly enough, I can play the clips back in camera. Just can't download them. Is this normal?

2nd question, anyone had more difficulty with DVCPro50 than 720P or 1080i? I've never had corrupt clips using the High def settings. Maybe I've just been lucky!

thanks in advance!

JP

 

[x002657]

My recent experience similar to yours.

My recent experience similar to yours.

This is lengthy, and I may not explain this clearly, as I'm trying to do a "brain dump" before I forget what I did to correct things. But, I stumbled onto something I didn't know before and may be helpful to others.

First, I use PPro 2.0, with CineForm's Aspect HD and HD Link under XP Pro, so this may only apply to Windows machines.

Shot footage over the weekend. Once-in-a-lifetime shots, far from home, of a college competition; absolutely could not be re-shot. Shot in DVCPRO50, used 2 P2 cards @ 4 GB each, multiple unloads over the weekend to HDD via 1394, except for the final shots that filled up the cards. Over the weekend I ended up with 9 partitions from unloading to HDD, plus 2 cards that were not unloaded.

When first bringing in clips from HDD to HD Link, then viewing conversion log, I got LOTs of errors. Most clips would not convert. Didn't get AVIs...didn't get anything. (Boy was I scared I lost irreplaceable footage).

As I looked closely at the clips, checking properties on the HDD, I noticed some clips on the HDD showed the same time of day as other clips. Couldn't figure that out...how could 2 clips have exactly the same time of day? Especially from the same unload of the same card? Exampe: a single unload of Card A showed 2 clips with the same time-of-day.

I still had 2 cards full of clips that hadn't been unloaded, but didn't want to "repair clips" yet, as I'm not sure exactly what "repair" does, and didn't want to risk changing or losing them. Also, at this point, there was no reason to "repair" those clips, as they were viewable in the cmaera and I had not yet tried converting them. Those last 2 cards I converted using HD Link only after connecting the camera to my computer via USB and switching to "USB Device" mode through the menu and "PC" mode using the "MCR" button. This way, I converted directly from the cards, not from the HDD.

I also had lots of clips on the HDD, from the many unloads I did over the weekend, that would not convert to AVI via HD Link.

When I noticed that multiple clips on the HDD had the same time of day, I decided to try converting them via HD Link in groups by time. Example: Clips 1 thru 6 showed sequential times-of-day, e.g. clip 1 at 3:07 PM Clip 2 @ 3:09, Clip 3 at 3:12, etc..

Clip 7 showed same time-of-day as Clip 1, e.g. 3:07 PM, but it's contents were different. Notice, different names and different content, but same time of day. Curious, ain't it?

I converted again, making sure that I was not converting multiple clips that had the same time-of-day property. Rather than convert an entire unload, I converted a handful of clips of "unload number 1", then converted a smaller handful of clips, also from "unload number 1."

What I did was use HD Link to convert Clips 1 thru 6, and all went well...I got my AVIs. Then used HD Link to convert remaining clips, and also got AVIs. This way, I ended up salvaging my footage without having to "repair." I also did not have to move the mxf files from the HDD back to the P2 cards to try to "repair" in the camera. (This was conveneint, as I still had valuable clips that had not been unloaded from the P2 cards).

I suspect (though I'm not sure) this may have occurred because after unloading multiple times over the weekend, I did NOT re-format the P2 cards...I simply deleted the clips, then shot more footage.

So, even though I unloaded with verify "On" over the weekend, and every unload ended with an "OK", somehow I suspect the time-of-day for each clip property got confused by either the camera, something in the 1394 communication, or my failure to re-format the P2 cards after unloading.

I'm not done converting all the clips yet, though thus far, my approach of converting only clips with unique time-of-day properties seems to be working. (I have been able to convert and save the most important ones, though).

Whatever the reason, I'd suggest you check the time-of-day property of the "erroneous" clips on the HDD, then convert only using clips with unique times-of-day. That might help.

I now suspect we're always better off re-formatting P2 cards after unloading and before recording again. It doesn't take long, and it appears to be worth the few secs it takes.

As for the reason, maybe others here can shed some light on this situation.

I hope I explained this clearly. If not, let me know and I'll take another shot at it...trying to get all this down before I lose track of what I did.

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