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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)."
How apropos.
'slashdotters' can eventually fade due to five things that affect the quality of slashdot comments:
Have you read my journal today?
I'm surprised to hear that consumer media can last so long. I was under the impression that consumer media would only last at most 20 years. Good to know it is longer.
Can I bum a sig?
"(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)." And NEVER ever feed them after midnight. On a more serious note, I used to worry about eventual degradation but it's coming up on 10 years that I've owned a CD-R drive and I have yet to run across a burned CD I cannot read due to this sort of degradation. Maybe at the decade mark, some of my discs will fail me and I'll change my mind but right now I'm not too concerned.
Brilliant. Now try reading them on another drive. See ya! /idiot
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.
Method of processing duck feet
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?
--
make install -not war
Taiyo Yuden All the way. They are great for copying PSX/PS2 games (seriously) where media quality makes a difference between burning out a laser or playing your back-up game, as well as DVD Movies.
The only drawback is that you can only order them from the Internet. I do not know of any retail store who actually sells the brand outright nor do I know of any brand (like Sony, Memorex, Fujifilm) who sells rebranded Taiyo Yuden discs.
Also, the Taiyo brand is more expensive than any other brand.
Previewing comments are for sissies!
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
direct sunlight in your parents basement. ;)
Repeating again and again and again:
For backups and archival you need tape backups, stored offsite. If you want something with more capacity and faster recovery, a backup server with rsync and beefy hard drives. Nothing else will do. With the time and effort you'll spend searching and writing DVD media you could have already bought and set up a file server or bought that tape drive.
Unless you're going to be taking those backups with you and using them in high volume, backing up to DVDs is simply a waste of time and space, and when you get some dreaded CRC errors you'll be crying for not having done otherwise.
sig: Cosas varias de un sysadmin argentino: http://aosinski.phpnet.us/
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.
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."
- spots.html
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
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.
The only way to get your stuff to last more than a generation is to chisel out yer 0's and 1's on clay tablets...
The reason being that DVD+/-R has the recording surface sandwiched between the two layers of plastic. CD-Rs have the recording surface on top, which can flake off unless you handle it very carefully.
Sure, you can handle the CD-Rs carefully and avoid this problem. But wouldn't you rather use a more reliable medium in the first place?
AccountKiller
Yeah, I get non-error-producing (in the burning process, I mean) misburns often enough that I ALWAYS keep the "verify burned data" option checked.
Takes way, way longer to burn a DVD that way, but it's worth it.
I order Taiyo Yuden DVD+Rs from MediaSupply.com. $25 for a spindle of 50.
Here's my two cents:
Stay away from Taiyo Yuden 16x media. I'm using a BenQ 1620 for all my DVD burning needs, and the PI/PO tests done on T-Y 16x media using DVDInfo Pro have always resulted in low quality burns. I am currently using 8x Verbatim DatalifePlus DVD+R media, and burning them at 4x. The results are truly unbelievable. The media code on the 8x Verbatims is MCC 003. I've heard through the grapevine that T-Y changed their media somehow from their 8x sets to their 16x sets, which has resulted in that the 16x DVD+Rs aren't as good. If you can get your hands on 8x T-Y DVD+Rs, then go for it; otherwise, stick with the Verbatim DatalifePlus series.
-BB
I have found this dvd media quality guide to be extremely informative. Yes, Taiyo Yuden is always ranked at the top (and is what I use), but they are not readily available at local retailers. It really helps to have a detailed comparison of various media instead of just saying "brand X is best".
I've seen Taiyo Yuden CD-Rs and DVD+/-Rs in a number of retail stores under various brand names. I'm hesitant to publicize my trick, but I suppose the Slashdot community should know. Here's how to spot Taiyo Yudens quickly in the store, without checking each label for "Made in Japan":
The spindles all have a unique bottom lip. Whereas most plastic spindle coverings are the same diameter from the top of the spindle to the bottom, Taiyo Yuden cases have a "lip" on the bottom of the plastic covering that starts about an inch from the bottom. The bottom of the clear plastic covering sticks out just a bit and then recesses to the diameter of the rest of the spindle. Taiyo Yudens comes in these cases no matter how they are branded, and I have never seen a spindle of discs with this bottom lip that are not Taiyo Yuden. I guess Taiyo Yuden supplies the plastic spindles as well as the branding on top of the disc.
In any case, I have had better luck with the consistency of Taiyo Yudens than any other brand of DVD+R. I'm not sure what the case is now, since I've only been using Taiyo Yudens for the past few years, but when DVD recording was first becoming affordable, the compatibility of much DVD media with various recorders was so terrible as to be useless (and endlessly frustrating). Taiyo Yuden makes quality discs, and it's always nice to spot them in the store when there's a deal going on.
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
Well, it's good to know that 95% of slashdotters are already following this practice by inherently storing their media close to themselves, next to their computers.
Lindsay Blanton
RadioReference.com
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.
"How to Do Nothing," kids activities, back in print!
Sometimes you need media immediately. Some people like to pick up media at the store. If you're going to be buying it at the store, why not get the good stuff, especially if it's the same price?
Additionally, it's not a guessing game once you know what you're looking for. If it comes in the Taiyo Yuden "That's" packaging and says "Made in Japan", it's Taiyo Yuden (unless it's a cheap imitation, which is still identifiable and not very common). People over at the media section of the CD Freaks Forum have discussed this to death for years. I will save you from hours of mostly non-productive reading by telling you that the packaging is unique to Taiyo Yuden, that fakes are not hard to spot and will not normally say "Made in Japan", and that most of the people on the CD Freaks forum, who have entirely too much time on their hands and enjoy obsessively testing CD-Rs and DVD+/-Rs with many official and hacked firmwares for dozens of recorders, agree that Taiyo Yuden is the best.
Taiyo Yuden FAQ, for those who want guidance in finding these discs.
Of course, if a disk gets a read error in the sector holding the FAT, I'm toast. :-)
Maybe not. PAR2 files store the filenames as part of the recovery data. As long as the TOC track (innermost track) isn't kaput, you can recover the data even if both the UDF and older 8.3 file tables are blitzed. If the TOC is busted, you'll have to get a professional DVD reader or go to a recovery service.
(The "how to" is over on the QuickPar forums. Basically, you rip the disk at the sector level to a pair of files. Rename the one with a PAR2 extension, then feed it the 2nd file as source data. QuickPar will find all of the data blocks and reconstitute the original files.)
Wolde you bothe eate your cake, and have your cake?
Up to this time, I had thought of my burned CD/DVDs as a "permanent" backup or record. This article has changed my thinking, and while I still like to buy "pressed" music CDs and DVD movies, and even download music from iTunes, I will now think of them as more permanent and acknowledge that MY burned discs will have to be re-burned from time to time. I am using LaCie CD/DVD burner and have had little problems with it and found it to be most reliable. As time goes along, storage space, via ethernet, is getting cheaper and cheaper and will provide more hard-drive space for direct storage of music and movies. I am preparing DVD storage of about 14,000 book titles from the Gutenberg Project and make them available to schools and libraries and compatible to Macs. Query: Should I learn how to make these discs "pressed" instead of burned? I am doing this under the guise of Scriptorium Library(TM) and will pay a 20% royalty to Gutenberg should the project get off the ground. So far, I have enough titles for about four DVD discs (about 4.5 gigabytes each). Cordially, Kris Kleeberg
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.