Archiving DV data - Longevity of magnetic media & other alternatives
A few years ago, I was advised to use magnetic tape to archive my video. This means keeping my original magnetic tapes and making another backup copy, using tape. This strategy has the advantage of being rather cheap and magnetic tape is supposed to be a pretty good way to archive video. However, I just had an experience that makes me question the wisdom of this strategy.
I had some 6- to 8-year-old Sony digital 8 (not MiniDV) tapes that I tried to recapture recently, but found the tapes have gone bad. The time code is shot and so is the audio, on every one of 22 tapes. They were stored in a dark drawer in my house, a few feet underneath my TV. (I wonder if the proximity to my TV led to premature dropouts?) The video is priceless, the first few years of my children's lives. Fortunately I have a backup copy of the data on hard disk (not tape), even though it was captured using an old version of iMovie several years ago. (I tested the Digital 8 camera by recording and playing back a few minutes of video on a new tape, and it was fine, so it wasn't the camera.)
If electromagnetic interference from my TV isn't responsible, that suggests the typical shelf life of magnetic tape is something like 5 or 6 years, and that's not very good.
I've read that hard disks aren't suitable for archiving data, because of the possibility of hardware failures (which eventually will happen) and the inherent impermanence of data stored on any kind of magnetic media. I'm not sure what the time frame is for data loss on a hard disk, but I'm guessing maybe 10 years if there is no hardware failure.
In any case, losing the data on those tapes was a wake-up call. I got to work and over the past 3 weeks captured (to hard disk) video from all the MiniDV tapes I've recorded in the last 3 years. I hadn't previously backed up these tapes. Thank goodness these tapes were still okay. They were stored in a different location, but I'm not sure if this made the difference.
Now I've finished capturing all my tapes and will be burning the unedited data to Blu-Ray gold archival discs, for safekeeping. Delkin makes these discs and they're expensive, and I had to add the cost of a Blu-Ray burner, but hopefully they'll last a good while. Delkin claims the data will be safe for 200 years.
I can't think of any safer way to archive video data than archival quality gold Blu-Ray media, except maybe Magneto-Optical discs which I don't ever hear of anyone using anymore.
I'll be interested to read the experiences of other people regarding the longevity of magnetic tape and other means of archiving video.
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