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How To Choose Archival CD/DVD Media

An anonymous reader tips us to an article by Patrick McFarland, the well-known Free Software Magazine author, going into great detail on CD/DVD media. McFarland covers the history of these media from CDs through recordable DVDs, explaining the various formats and their strengths and drawbacks. The heart of the article is an essay on the DVD-R vs. DVD+R recording standards, leading to McFarland's recommendation for which media he buys for archival storage. Spoiler: it's Taiyo Yuden DVD+R all the way. From the article: "Unlike pressed CDs/DVDs, 'burnt' CDs/DVDs can eventually 'fade,' due to five things that affect the quality of CD media: sealing method, reflective layer, organic dye makeup, where it was manufactured, and your storage practices (please keep all media out of direct sunlight, in a nice cool dry dark place, in acid-free plastic containers; this will triple the lifetime of any media)."

9 of 225 comments (clear)

  1. Bummer by Deagol · · Score: 3, Interesting

    I always thought Matsui "Gold" and "Silver" were the top-rated media. At least for CD-Rs (though I thought they were held in high regard for DVD blank media, too). I used to mail-order un-branded blanks them by the spool.

    1. Re:Bummer by greg1104 · · Score: 3, Interesting

      Mitsui's gold media has generally been considered the best available for CD-R work, particularly from an archival perspective. The company has reorganized and now goes by the name MAM. If you look through the comments after the article, the author suggests that the currently available MAM media isn't as high of a quality as the older Mitsui discs. I would like to see some citation for that fact, as I wasn't aware the formulation was changed at all from that reorg, but I haven't researched this subject recently enough to be able to dismiss his suggestion outright.

  2. Safety in Numbers by Doc+Ruby · · Score: 3, Interesting

    Cheap but adequate DVD-R media costs $200 for 1000 discs, about 4TB capacity. And a cheap DVD-R changer jukebox costs under $500, about 800GB per load.

    Why not just burn a few copies of the archive to a bunch of DVD sets? The DVDs will get defects, but shuffling the chunks across the discs just a little will probably ensure that the random distribution of specific defects will not hit every copy of a given bit, against the odds a low defect rate will produce.

    How about a pair of those archivers, which fire up every few years just to transfer the aging DVDs to fresh new ones? For another $1000, that's another 5 cycles of DVDs, 800GB per cycle. Another $1000 gets a pair of backup jukeboxes.

    For higher capacities than 800GB, there are pricier pro jukeboxes, but with dual drives for the retranscription cycle (and faster restores). But the architecture is the same. Why try to make the media more reliable, when there's cheaper/easier solutions that just accept unreliable media, and move on?

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    make install -not war

    1. Re:Safety in Numbers by Doc+Ruby · · Score: 3, Interesting

      With the single DVD jukebox, the first 800GB is online at one time, for $450. A 750GB HD costs $350. But the next 800GB in DVD costs only $40 - each 4TB costs $200. And there's no limit to how many $50 TBs you can archive, with a sizeable enough closet. The downside is un/loading the jukebox, 200 at a time. But that's archive, "nearline" storage.

      Plus, you get a DVD reader and writer. For dealing with the DVDs (and CDs) that still distribute lots of content as a transfer medium. And for those without distributed endpoints to where they can archive data, or insufficient network bandwidth to archive all their data across the WAN frequently enough, DVDs are good and cheap offsite archive repositories. Plus you can burn DVDs that will play in every consumer player, which can connect your data to lots of people without data processing HW. HDs are a cul de sac for data, trapped within the infosystem.

      DVD archiving isn't really competition to online HD storage. It's complementary, in different use cases, different user environments. There's considerable overlap in their related extremes, but there's a lot of difference that makes leaves the DVD solution worthwhile for many scenarios.

      BTW, while I'm offering detailed factual analysis of HD vs DVD mass storage, don't throw in your "opinion" that "it's absolutely stupid...". Especially if you're going to offer a disagreement worth considering. Do you want to work together to figure out the real merits in a debate, or do you want to get into an obnoxious pissing contest that few other people will want to wade through? Few people worth teaching will learn anything from such unnecessary conflict. Including ourselves.

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      make install -not war

  3. Not a concern with MY optical media by loimprevisto · · Score: 3, Interesting

    I have some movies on laserdisc that're pushing 20 years, and I haven't had a problem with them yet!

    --
    Much Madness is divinest Sense --
    To a discerning Eye --
    Much Sense -- the starkest Madness
  4. I have CDs good since 1998 by scottsk · · Score: 4, Interesting

    I now have some no-name-brand CDs burned in 1998 that are still good. I have never had a good, name-brand CD fail for any reason. The only failure I have ever had was the top layer peeling off some el-cheapo CDs which were stored in plastic sleeves, not jewel cases. One BIG key the article does not mention is to store the disc where the burned surface is not touching anything, such as in a jewel case -- the article should have mentioned that. Do not put in plastic sleeves or cases with slide-in sleeves. Odd that the article is a sales pitch for that T-Y brand -- what about RiData? That's what I use for DVD archival storage. I haven't been using DVD-R long enough to comment on how long they'll last. I have always found the alarmist idea that CDs will spontaneously self-destruct to be sort of over-the-top. CDs seem much more reliable for archiving than any other medium like diskette, hard disk, USB flash, or tape. Flash is more reliable, but has to be refreshed or it will disappear.

  5. my experience: some DVD media dies with no reason by Anonymous Coward · · Score: 3, Interesting

    One Maxell DVD-R I burned in Sept. 2003 went bad within 3 years, despite every detail of the burning, readback, handling, and storage being in accord with the advice I've seen posted. An email to Maxell support on this issue had the reply: "The media if stored properly will have a life of at least 50 years."

    Possibly relevant, I noticed an internal pattern of small spots visible with a loupe or macro lens (on order of 10 microns in size; much larger than the data pits). You can read more about it here: http://www.bealecorner.com/trv900/DVD/Maxell-DVDR- spots.html

    Maxell America agreed to take back this DVD for analysis. As instructed I sent it to their Fair Lawn, NJ site. It was received Oct. 5 2006 and Maxell acknowledged receipt. They have apparently done nothing with it since, despite several emails to them in the ensuing two months.

  6. The usual vague personal testimony... by dpbsmith · · Score: 5, Interesting

    Oh, I'm so tired of these articles. Everyone concentrates on dye fading, because I guess it's easy to measure and quantify. If dye fading were the failure mechanism for these disks, they'd last twenty to two hundred years... according to vendors and researchers.

    Everyone says "I've never had any trouble with brand ABC," but the thing is, ABC varies depending on what you read or who you talk to. Some people insist they've never had any trouble with the cheapest generic products they buy at Staples. Some say any name brand is OK. Some say Verbatim is good. Some say to stay away from Verbatim. The more sophisticated will tell you not to use anything but phtalocy- pthalocy- pffthal- the Mitsui stuff. Others (like this guy) are partial to other dyes. Some say you're a fool to use anything but Mitsui Gold... some say they're an overpriced waste of money.

    It's all authoritative sounding talk, talk, talk and no two experts say the same thing.

    In reality, I don't think anyone understands very well what actually causes these disks to fail in the real world. I've had disks fail in less than two years--maybe only a couple-three in many hundreds, but certainly not zero--and I've never seen any obvious pattern as to which of them fail.

    The thing that really bothers me is that drives and/or their accompanying software drivers never give you any indication of what the signal quality of a particular disk is. If they did, you could detect that a disk was deteriorating before it failed, and make a copy. As it is, they just keep silently keep correcting errors behind your back and you have no warning until there is utter, catastrophic failure.

  7. independence by chucken · · Score: 3, Interesting

    Am I the only one to be suspicious about the impartiality of this article? Check out the links. Quite a lot go through the weird ass domain name JDOQOCY.COM. Do a whois on this domain and you'll find the registrant is "Commission Junction". Hmm, impartial, NOT.