Posts Tagged: High Definition

Don’t pull that cord!!! some XDCAM pdw-u1 gotchas

When the company I started at transitioned into high definition acquisition, due to our purposes the XDCAM format was the only solution. We certainly looked into some of the P2 cameras, but there was not a trustworthy or economic way of archiving the raw footage then. See our primary client was a large aerospace company that, in addition to full productions, needed plenty of events and processes solely documented. This massive amount of raw footage may or may not be used down the road, but it had to be there just in case. We had a warehouse full of old media captured for them over the years; Betacam, D2, One inch, film, you name it we had it stored there. Well, in the new HD era then, and even more so today, the majority of capture is tapeless. We couldn’t rely on hard drives or use the extremely expensive P2 cards as an archival medium, so we went with the full size Sony PDW-F355 camera that shoots to 23 Gb and 50 Gb Professional Discs. These discs are about the same cost as the 40 min digibeta tapes we were accustomed to shooting with and you could pull them out of the camera and throw them on the shelf without having to worry about the data becoming corrupted by time. In addition, the discs are extremely durable; I have seen them dropped plenty of times with nothing but small scratches on the hard outer plastic protecting the internal Blu-Ray disc. These are in large part why many of the reality shows such as Survivor and Road Rules chose this camera.

So in order to actually use this footage you need to use a device to transfer the files to your NLE. Go figure. You could use the camera itself, but that’s not practical. Enter the PDW-U1, a nice little disc reader for these Professional Discs. It doesn’t have deck control or any video inputs or outputs, but using USB it can read and write XDCAM clips. With anything that involves 1’s and 0’s there is potential for corruption, and there are 2 ways I know of where the PDW-U1 will ruin the precious footage you have on your XDCAM disc.

1- Don’t pull that cord!!!

This is one of those things that should speak for itself but you don’t discover it till an Oh, $h*% moment is upon you. Luckily, it happened to us while mastering to a blank so it didn’t destroy anything irreplaceable; but the scary thing is it could have. We had 3 editors sharing one PDW-U1 and while a final project was being mastered back to XDCAM disc for archival the USB cord was pulled from the machine. When this happened the disc became unreadable. It wouldn’t show up in the Sony clipviewer, it wouldn’t mount as an external drive, and it certainly wouldn’t allow any import into Avid. Now, I might be able to understand the clip that was being written becoming corrupted, but for some reason the entire disc becomes corrupt. Again, luckily this was one of the first clips being written so after a quick reformat of the disc we were back on track without too much time lost. But think if this was a master disc with months and months worth of final projects on it. Think if all these old projects were now offline and you didn’t have a clone of the XDCAM master to go back to. Wow, that sucks to think about. So don’t pull the cord, unless you are sure that it is not accessing the XDCAM disc while you pull it. Better yet, eject the disc from the reader before you pull the cord. Peace of mind is so nice when considering the alternative. Now, I would hope and expect that if you were reading from the disc with the write lock on, this act of cord pulling would not have an effect. I have not had the chance to test this one, nor the stones to test it on raw footage, so for now it is speculation.

2- Don’t delete those clips!!!

This is another gotcha I discovered while trying to make a master disc for a collection of recent projects (that were still online, thankee sai). I wrote back 2 clips, but they were not in the order that I wanted, so I accessed the disc through the explorer window and deleted the first clip. My thinking was I could rewrite the deleted clip and it would now be in the proper order. Boom goes the dynamite! Same result as pulling the cord. When I messed with the clips on the disc, it made the whole disc corrupt and unreadable. I am guessing that the file structure on the disc is similar to that of a BPAV folder from an EX-1, when you mess with it everything ceases and desists. This is a careless misstep I could see happening if you were trying to get rid of bad takes or clearing up space on the disc for reuse. If you went into a disc with 50 or so clips and wanted to get rid of 10 or so mess-ups it would render the entire batch corrupt. The thought makes me shutter. With the camera you can delete the last clip on the disc, but not selectively delete. I am guessing this file structure issue is at the core of that function. So when that raw disc is full and out of the camera, write lock and forget about it, because otherwise great anguish awaits.