(Or, “In Which Your Narrator Learns a Valuable Lesson About The Perils of Cheap Media and the Proper Use of the Verify Button.”)

A while back I picked up a 50-pack ‘cake box’ of surprisingly low-priced DVD+R Dual Layer discs, possibly at Costco (although it could have been Best Buy or Staples, at this point I’m not sure). The price was good and I’d been thinking that it’d be nice to be able to cram more than an hour’s worth of DVD-Video onto a disc, and I naively had some idea about using them for backup purposes as well.

The discs were TDK branded, and say “DVD+R Double Layer 8x Speed 8.5GB”. Unfortunately, what the label doesn’t say is that, as far as I can tell, the only relationship they have with actual recordable DVDs is that they’re roughly the same size and they have a hole in the middle. But more on that later.

Anyway, I bought the discs, brought them home, and promptly forgot about them. I don’t burn a ton of discs anymore, but it’s good to have media on hand…right? So there they sat, lurking.

A few months ago, I went to burn a fairly big photography project to disc for safekeeping. Of course I had it backed up to a second hard drive (via Aperture’s ‘Vaults’ feature), but I figured an additional copy on optical wouldn’t hurt. And so I clicked away in Toast and burned the files to one of the discs.

Now I generally make a point of always letting Toast verify any disc I burn, but I’d be a liar if I told you that I actually remember doing it. It’s possible that I just mounted the disc immediately after burning, cataloged it, and then ejected it and put it with my other backup discs. Rinse, repeat … about a half a dozen times or so, over the space of a few months. Each time the same process — I burn a disc without problems, mount it, catalogue it, and then put it away in a binder. The process wasn’t flawless — sometimes I’d get failures due to ‘sense key’ errors and have to try a couple of times to get a successful write, and writing 8.5GB at the maximum speed of 2X that my writer supported was slow — but I figured that was par for the course.

Up until earlier this week, when I did something different. I burned a bootable disc image (long story) and attempted to use it on another computer. It failed. In fact, the disc wouldn’t even mount when I put it in the other computer’s drive. Thinking it was a compatibility issue, I brought it back to my desktop where I’d burned it — nope, nothing. Odd, I thought — so I tried it again, and got the same result.

Although the disc had mounted just fine immediately after burning, once ejected from the drive and reinserted, it would never mount again.

Not only was the boot disc bad, but every disc I’d burned on the media turned out to be bad. That’s right: one hundred percent mis-burns.

In the interest of science, I blew through most of the rest of the stack trying different burning programs, data, and writers. I achieved identical results with my desktop’s Pioneer DVR-109 and my laptop’s LG GSA-S10N6, using both Toast and Apple’s Disk Utility. No dice under any combination. (On the LG, the discs seem to fail more reliably during burning; on the Pioneer they sometimes complete and fail silently.) However, the error does seem to be reliably caught if full post-burn verification is run on the resulting disc.

So, lessons learned:

1. Always run a full verification cycle on every disc, every time. I got sloppy, and as a result let a few bad discs slip through into my backups. No harm came of it, and they’re a belt-and-suspenders thing anyway, but it’s not hard to imagine how it could have been a nastier surprise. If it’s worth burning, it’s worth verifying.
2. Brand names on optical media are totally meaningless. I’ve discovered the crummy “RITEKS04” stuff under both the TDK and Memorex names. It seems to be the case that if you’re getting a ‘good deal’ on double layer DVD+R 8X media, what you’re getting is probably the RITEK crap. Avoid it like the plague it is.
3. Allegedly, the only decent DVD+R DL media around is Verbatim. I wasn’t able to find any in any local stores in my area, although it is available mail-order. In general, the whole double layer system seems half-baked and worth avoiding unless you really need it.
4. DVD burning isn’t like CD burning. Or at least not like CD burning in the last ten years. I was cavalier about burning DVDs because I mostly burn CDs, and CD writing technology has been pretty reliable — even with cheap non-mail-order media — for the better part of a decade now. DVD burning, especially double layer, isn’t like that; it’s like 1999 all over again with the weird incompatibilities.

It’s entirely possible that there are burners out there that handle the steaming pile that is RITEKS04 just fine, but both of my drives are common models (both are stock Apple parts) and work fine with better grades of Verbatim media.

So much for a good deal on a box of discs.