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Best CD or DVD Recordable Media for Longevity?
icepick72 asks: "I have recently purchased a collection of music (on CDs) for a music group that had their final tour last month. Without getting into copyright issues (I'm writing from Canada -- not that it necessarily makes a difference) I would like to know if any CD-R media on the market supports longevity. In the past Slashdot has discussed the degradation of CD/DVD media. How do I go about knowing what the good media is nowadays, and how to get a decent price on it? One company uses this foil or that foil while another uses polywatchmacallit. Looking for good suggestions, and an archived discussion on Slashdot for future reference."
Well, you could rip it to your favorite format and throw it in a spare hard drive with an external hard drive USB (or firewire) box. This should be able to hold even .WAV files (unless they released over 200 albums).
When USB begins to be phased out for something faster, simply buy whatever the newest hard drive and interface flavor-of-the-month is, and copy from the old HD to the new.
If you are really paranoid, you can just get two drives, and keep them in separate places (preferably separated by 1000 miles or more).
And if you add to that CD-R backups, then you should be prepared for anything.
"-1 Troll" is the apparently the same as "-1 I disagree with you."
You just can't spend 30p or whatever on a piece of mass produced plastic and expect it to last more than a year or so. It's just not going to happen. DVDs are the worst - I've written slowly to write-once DVDs and not been able to read it back immediately after, or maybe it'll work for a few months then stop - it has very few scratches and I treat it really carefully but still a few files don't work. I'd stick with hard disks.
With external/portable hard drives these days looking much cheaper, I would say that your best bet is to check one of them out.
My UID is a palindrome, that must be good for some type of prize.
The NIST site that hosts the article you mentioned has some tips on specific media types, but trying to buy them in small retail quantities isn't alway easy. There's rarely any guarantee that on opening two identically packaged boxes from a media company you'll end up with identical media.
For some anecdotal info (and links to even more anecdotal info), check out the section 7 of the CD-Recordable FAQ
http://www.cdrfaq.org/
To add one more statistically questionable story to the pile, I know several recording studio techs who swear by Mitsui. They're a little more expensive than generics, but you can buy 50 or 100 disc pack from the company itself (or an official distributor) and be reasonably sure of what you're getting. I've had only good experiences with them myself.
But then I've had very few bad experiences so far with any media, and all of those have involved generics with gummy printable labels applied to them, and all were given to me by other people. (My own paranoid technique is to label disks only with a non-alcohol based felt tipped pen.)
On the other hand, if you're goal is archiving the irreplaceable (rather than just stuff that will be expensive to replace), it's hard to beat a pair of hard drives which contain flac (or, if disk space is cheaper than processor time wav) files and checksums for every file. Every year or two you plug in each drive and make sure all the files are good, and when it starts to become hard to find systems that will interface with your old drives, you transfer everything to new ones. When you can pick up a 200 gig ata drive and a USB hard drive enclosure for well under a hundred bucks, it's hard to argue against that sort of strategy. You could do the same with DVDs or even CDs, of course, but checking them becomes a manual hassle.
In any event, make two copies of everything so that if one goes bad, you are likely to have a backup. Keeping one somewhere other than your house doesn't hurt either.
If you're really serious about the longevity of your data, you probably should get it backed up onto a commercial dvd. Otherwise, just use a DVD-R or something.
I dunno what the other guy was complaining about when he said he couldn't read it straight after he burnt it. Here's a hint: Maybe it's not the disc? Maybe it's your burner. I've got DVD's lying around the place from years ago that I've burnt at 2x and they still work.
Anyway,
Serious: Commercial DVD
Not so serious: DVD-R
Half assed solution: Put the files on Bittorrent and hope someone's seeding in the years to come.
I'll subscribe to Slashdot when I see a month without a dupe, a typo, or an article the "editors" didn't read.
rippify to a nice open codec that won't lock you out, then upload to gmail. My bet is its totally safe for years and years to come...
DYWYPI?
I'm using some of these Gold DVD-R's. After doing some research I picked these. They are supposed to have a shelf life of 200 years or something if treated and stored properly.
I bought them at this Canadian retailer...
http://ncix.com/products/index.php?sku=16000
I'm really not sure what the difference is, but the music CDs I made back when CDRs were expensive ($10 for 5) still work great for me ... that's like back in 99 - 00. Now, newer CDs seem to go bad in a 3-6 months. Not sure why.
You don't want to buy better media, you want more copies. Keep at least 2 copies of every cd, and make new copies every 1-2 years to avoid degredation problems. Its cheaper and more sure.
I still have more fans than freaks. WTF is wrong with you people?
Basically, you want the surroundings to be chemically inert. We always put all our DVDs and CDs in ZipLock Freezer bags, Quart size. The package says they have a "FreezeGuard Seal", which means that you can expect that all moisture is excluded.
Freezer bags have extra thick plastic, which provides good, slippery, mechanical protection, too.
If you expect to store the DVDs and CDs for a long time, put the Quart size bags inside Gallon size Freezer bags.
For extreme protection, go to a shoe store and ask them for those little packets of dessicant (moisture remover) that are in each box of shoes. They'll give them to you free. Put one in each Gallon bag. I don't put them in the inner bag because the impurities in the dessicant granules might be abrasive.
We do it all the time... at one Client's LAN (in a Windows shop)
- bring up Nero,
- create an ISO (by copying a disk or creating one).
- after the ISO has been created, interrupt the process before burning a disk, &
- if it helps, WinZip the ISO (eg, a big
We can always (ie, for as long as the computer & hard disk survive...)
create a disk (oh, we'd need to stockpile CD-R media, I guess...)
Verbatim is awesome stuff......they have a limited lifetime warranty! I have never had problems with bad discs. They are sometimes more expensive, but well worth it.
The original stamped CDs will out live any CDs from a burner. Create CD images from the originals and possibly FLAC files. Put the original CDs away and never touch them again. Copy the cd images to DVD and copy the DVD every couple of years.
For photos, backups and other archival stuff to CD or DVD I've been adding PAR parity files. They're sort-of like RAID at a file level. Even though the initial use of .pars was for Usenet binary downloads (I think) the tools work great for any situation where partial loss of data is likely. In theory, as long as the unreadable bits of the disc are a small % of the disk, I should be able to rebuild the data. There's an article where this is tested by scratching / drawing on a CDR -- unfortunately, I don't have a bookmark. The chances are good that a disk will not go bad uniformly across the entire disk. So, the parity files should be able to recover from most scratches and a lot of bit rot.
.par files are better than making 2 copies of the same data. For example, if you're only backing up a few large files, the odds of having both copies of the file get a few bad sectors is relatively high. I suppose you could patch over unreadable bits with a hex editor or something, but I'll take a nice GUI and relatively common software anyday.
Plus, I feel that
Although, to be perfectly honest, I just don't rely on CDR or DVDR. I keep a copy of all stuff on a hard drive too. DVD's go offsite, HD stays at home.
Just search for "archival gold" media. A few companies make it. Most of the degradation comes from the aluminum reflective layer oxidizing, and using a gold layer prevents that. Simple, effective, and not that much more expensive.
Personally, I prefer magneto-optical for the important stuff. Disappearance of the SCSI interface will make the drives unusable long before the media degrades.
Nothing against Verbatim, but lifetime warranties mean nothing on CD or DVD media. All that means is that if you mail in the now-defective disc, they'll send you a blank replacement disk. So it costs them a couple dollars including postage to replace your defective discs, but you still lose your data. And how many people actually mail in their defective discs instead of chucking them in the trash and buying a new spindle?
"Those who consume the bulk of goods are those who make them. We must never forget this secret of our prosperity."
TDK CD-R media had a 100 year guarantee printed right on the package. I can't tell you if it was BS or not but TDK seems to take their work seriously. No rebranding, new R&D (that scratchproof coating) and pride in their work. They even have a CD-R for long term digital photo storage. I can't tell you if it is really anything special or just marketing BS, but take a look.
Any how the biggest killers are UV, heat and moisture. Stop those 3 and you should be making the most of any brand. Mabey inside a pelican case w/ desicant inside a bank safe deposite box? Ehhhh overkill, I know.
You could use media that is designed for long term data retention, and it typically kept readable by design of next gen hardware... LTO tapes kept in a controlled environment.
Not everyone has a robotic library backing up their workstation - but even a gen or two older desktop drives are obtainable. Media isn't the cheapest, nor is it great for easy access - but when your CD-Rs fail, and the hard drive you had saved the original AIFF files fails... the LTO tapes are still there.
FWIW, I've (ab)used a variety of CD-Rs in my car CD player, subjected to extremes of heat and cold, and found that both the Imations and the TY Fujis have held up well. Scratches have caused me more trouble than environmental conditions.
Oh, no! You have walked into the slavering fangs of a lurking grue!
Use RE-Writables, not WORM.
RW discs:
*blanking aneals metal-layer in disc
*burning quick-melts spots of metal in disc, so they freeze quickly to different crystallization than the annealed "normal"
*reading means reading the changes in reflectivity that occur ( or differences in polarization, in magneto-optical, IIRC ) in the METAL reflecting the laser-beam.
Write Once discs:
*new disc is "blank"
*laser "burns" organic-dye in writing,
*reading-laser "sees" the diff between burnt and non-burnt as less-transparent vs more-transparent, and the reflective-layer behind-it means that this is usable binary encoding. . . ( beam goes through organic-dye twice and then is read, or perhaps gets-eaten by the burnt dye and then its absence is read. . . )
*organic-dye decays
IF you care about archival, you then store complete versions of your files,
with checksums and ECC on RW discs.
IF you are using organic-dye write-once discs, then you are basing your ability-to-recover your stuff based on Estimates & Marketing Claims(tm). ..
Cheerses
IPTables enhancement Fail2Ban bans cracker-login's
Well, there's what banks do with their optical media, which is have the glass master stored in a safe deposit box. A glass master for a DVD costs about $1000 , CD costs about $700. (Googled from http://www.cddvdking.com/ ).
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Barring that, you can buy TDK professional media ( http://www.tdk.com/professional/ )
Also, googling for Archival CDR reveals a review on the subject by photo.net at http://www.photo.net/mjohnston/column53/, which leads to the $3-a-disk Archival stuff here. http://store.mam-a-store.com/standard---archive-g
Hope this helps.
o/~ Join us now and share the software
I don't know but now when SUN has delivered ZFS wouldn't regular harddrives in a raid setup with ZFS be close to optimal? All data is protected with a 256bit checksum and gets fixed if the system finds an error.
:)
Only problem is if the whole system dies (that is if it's always connected and something like the lightning struck or the place burns down and so on), I guess you could send everything over to another machine somewhere else to.
So two separated Solaris machines with atleast 2 harddrives and zfs will do, I guess
I have quite a lot of data (>800GB and growing) I want to keep for at least twenty years, on a budget. Currently, I am using DVD-R.
.PAR2 files, is created by QuickPAR and other tools. Basically, with parity data, if some of your actual data becomes corrupt, you can recover it. I usually create 5% parity data, which means that if 5% of my data becomes corrupt I can still recover it. If 6% becomes corrupt, I'm stuffed. So, for very important stuff, I use 10% or even 25% parity data. Remember to burn the parity data to a different disc, preferably stored in a different place to the disc with the actual data on it.
I only use Taiyo Yuden DVD-Rs, with a Pioneer 108 DVD-RW drive. Taiyo Yuden invented the original CD-R, and are the only company that still makes discs in Japan. Their discs have excellent quality dye, and provide good quality burns.
When determining how to burn discs, some experimentation is needed. Try different speeds. I have found that a 12x burn gives better quality (i.e. fewer errors, no burn is perfect) than 8x on Taiyo Yuden 8x discs with my burner, but other drives may be different. Try using tools like Nero CD-DVD Speed and DVDInfo to check the number of errors, and that your drive can read the discs at maximum speed all the way to the end. Take a look at the CD Freaks forums, particularly the media tests sub-forum for more info: http://club.cdfreaks.com/
I always create parity data. Parity data, in the form of
A note about PAR2 files and DVDs. If your DVD becomes unreadable, i.e. you can't see the filesystem, rip it as an ISO image file. Use a tool that can skip errors, like ISOBuster. Then, use the PAR2 files to try and recover data from it. PAR2 is clever enough to find useful data blocks inside the ISO.
Don't use anything silly like multi-session discs, and make sure your PC can keep up with your burner so that you don't need to rely on "just-link" or whatever they call it. Make sure you verify data after burning (Nero can do this automatically).
Store the discs in a cool, dry place. If you are on a budget, metal "flight case" boxes with CD wallet style holders are a good bet if you keep them in a cupboard out of the light. Don't use flexible wallets. If you have the money, there are commercial storage systems designed for very old books which would probably work well.
Also, be sure to check discs every few years. I generally test a sample of my discs once a year. If any of them show signs of degrading, such as no longer being able to read at maximum speed or high error rates, I re-copy them. My oldest Taiyo Yuden discs are now four and a half years old, and only one (which I may have mishandled) has started to fail so far.
If you are really paranoid, you could keep the parity data on magnetic tape or hard disc. The advantage of only keeping parity data on these more expensive mediums is that it's usually only 5-10% the size of the actual data, which keeps costs down.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Verbatim's DataLifePlus brand /usually/ means that the disc is rated for a 100 year shelf life with a scratch resistant plastic. Also note that their DVD brand will have an even greater life span due to the fact that the film on a DVD disc is sandwhiched between two layers of plastic. On a CD, the film is exposed to the air.
The discs are also inexpensive. You can pick them up from places like Provantage for under 75 cents each in spindles.
I've read that Silver is better than Gold. I guess one just expect gold to be better.
I agree with you. However, the chemicals in ZipLock bags don't seem to affect DVDs or CDs.
What if you put the disk in a slim case and THEN into the ziplock bag?
Bottles.
Gold's less chemically reactive silver, so I think what you've read could well be wrong...
Car analogies break down.
I think it was because the silver surface reflects more light.
Was probably on dvdrhelp or something, can't remember thought. Back in the days I also expected gold to be better than silver. Read this only a few weeks ago.
The slim case will add strength, if you need that.
However the chemicals in ZipLock bags are acceptable to be next to our food. I doubt they will be a problem for DVDs and CDs.
I still have some Kodak CDs that I recorded in 1998 and they still work perfectly, both for data and audio. About DVDs, I'm used to buy "LGs" (at least they are labeled LG, but cdrecord says they are SMC Magnetics or so), but I don't know if they are really reliable... I have been using then for about 6 months and they still work, but I don't expect it to last more than 2 years. I'm looking forward to know what others /.ers will say about reliable medias.
Regards,
Gustavo
Fuji still uses Taiyo Yuden for some of their CD-Rs. When looking at the packaging, look for Made in Japan to get the TY instead of Made in Taiwan. Lately, I've only found the Taiyo Yuden in 30-paks. I gave up using anything else a long time ago, and returned the first Taiwanese Fuji CD-Rs that I bought right away.
http://www.dvdisaster.com/ Generates error recovery data from a DVD and writes it to a "backup" CD. Of course, you have to worry about the CD now as well, since you've got nothing protecting it, but CDs were always more scratch tolerant than DVDs. As for environmental effects, I recently pulled some ~10 year old floppy disks out of a cardboard box in a closet (Borland Turbo C) and they worked just fine, so a jewel case would probably protect optical media at least as long. S
Kodak Gold CD-Rs. Last I checked, they were only available in 650 MB, but I have some that I burnt 6 years ago that are just as good as the day they were burnt. They get scratched much more than my other cds, and still work much better.
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Dessicant from the shoe store is probably completely hydrated after being in a cardboard box for several weeks or months. If they use normal silica gel inside the packets, you could just heat it up in the oven to dry it off (250 F or more)... but the paper might not survive... I've never tried heating it in packets. Your mom or grandmother or some other female in your life (sorry to be sexist) might have some plain silica gel around (used for drying flowers) and chances are it has the color detector in it that turns pink when hydrated and blue when dry. Then you could dry it out and just make your own little packet you can be confident sucks (water, that is).