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Burned CDs Last 5 years Max -- Use Tape?
Lam1969 writes "Computerworld has interviewed Kurt Gerecke, an IBM storage expert and physicist who claims burned CDs only have a two to five-year lifespan, depending on the quality of the CD. From the article: "The problem is material degradation. Optical discs commonly used for burning, such as CD-R and CD-RW, have a recording surface consisting of a layer of dye that can be modified by heat to store data. The degradation process can result in the data 'shifting' on the surface and thus becoming unreadable to the laser beam." Gerecke recommends magnetic tapes to store pictures, videos and songs."
Magnetic tape? Ok
Anyone know where I can download an MP3 jukebox for my Vic 20?
Those are records. I don't know about you, but I don't have an LP-ROM drive.
Haven't other studies confirmed much longer lifetimes in the past for CD-R? After all, we've had CD burners for longer than 2-5 years. Is this only a surprise because absolutely nobody has ever gone back and tried to read an old disc? Somehow I'm still doubtful of his conclusions.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
I have CDs that have lasted 10 years with no errors. Obviously 5 years is not the maximum life. Perhaps the maximum EXPECTED life.
We've known that CD-Rs will degrade for a long time. Hispace have recently launched a new range of CD-Rs aimed at digital photographers. These disks use 24 caret gold to help add stability to the disks. As a result, they come with a 100 year warranty.
Your porn will be around for decades after all!!
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The wedding photographer for my wedding gave me a DVD of the video + photos. After about two years the DVDs were so degraded that I could not a single DVD player would recognize them. And that's with light usage... Now I keep important DVD as images on an external hard disk.
When I first asked this question of how long CDs will last, I was told about 70 years.
I was also told that to lengthen a CDs shelf life, always store them vertically in a cool dry place, and clean them from the inside ring to the outer edge in a straight line.
I found an article from the Optical Storage Technology Association and they say it depends on the initial CD quality and handling.
According to this article, unrecorded CDRs last about 5-10 years, manufacturers claim recorded CDRs 50-200 years and recorded CDRWs 20-100 years.
More info: http://www.osta.org/technology/cdqa13.htm
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I just recently tested ~120 cds from about 1999-2002.
Attempting to read them with a DVD drive failed many discs.
But reading with a CD drive I was able to read all of them (after some cleaning) except two (most files were readable) that were scratched.
It seem there is some difference between DVD and CD drives.
Most CDs were burned with 2-8x speed, I almost never use >16x today.
Isn't the cost point close enough yet to just use hard drives instead for long term storage and not be too bad?
You can pick up OEM 250GB hard drives for around $100. Toss in a $50 USB case or a SATA case and you're looking at $1.67 a GB storage. Plus you're not limited to 4.5GB file size.
Sure drives fail but you won't be spinning them that often. I'm begining to think it may be worth it for the long term. Then use the USB drive or SATA as needed and if need be burn a disk.
NIST Did a study that shows up to 30+ years of longevity that is totally dependant on handling and storage.
Great. I lose hundreds of precious photos. They give me a buck.
"I'd rather be a lightning rod than a seismometer." -Ken Kesey
Most serious photographers I know re-burn their archives every one or two years.
1. depressingly high failure rate of hard disks
I find hard discs insanely more reliable than they used to be. I was building PCs in the 80's and I experienced the wonder of buying a full 20-count box of Seagate hard discs, and have EVERY DAMN ONE OF THEM FAIL IN 3 MONTHS.
I currently have 8 Maxtors and Hitachis of between 160 and 250 GB spinning in 3 machines at home. Most are > 2 years old. No problems. My older 40 and 80 GB machines have been given to friends to use in their older machines. They haven't had any failures either. I can't remember the last time I had a hard drive fail.
If your case is such that your hard drives are hot to the touch, don't blame the drive for failing. I think that's what causes most of the failures.
The article says to use magnetic tape because the CDs degrade.
So does tape. Unless you're the BOfH, in which case you have a tape safe. But you can't use that to store tapes - its not climate controlled, and you've got too many bodies hidden in it anyway ... but ever tried to read a 10-year-od tape on a new machine? I gave up - it was easier to connect to a serial port and just dump the whole database over the course of a week, its that bad. Then another day for updates. Todays USB and Firewire will be the next generation's serial ports.
So, use a hard drive?
Leave it sitting on a shelf too long and you get "stiction" - so that's no good either. And have you even TRIED to access a 10-year-old drive in todays machines? The bois tries to auto-config, and the machine won't boot.
Zip disks? Hahahah click of death hahahah (I've got several zip drives that are "unzipped")
Paper printouts? Well, those are good for a few decades, but not exactly portable ... anyone care to figure out how many acres of trees a hex dump of a 200-gig drive will take?
Nope, stone tablets - to hit anyone over the head with who thinks that there's any real long-term solution other than to just re-copy to the latest format and pray.
Another comment:
This is a quote from the story: "His recommendation: a hard-drive disk with 7,200 revolutions per minute." That's a way to have secure storage?
That's a recommendation? It's quite obvious that the author of the referenced story, John Blau, has no technical knowledge.
Another quote: "Kurt Gerecke, a physicist and storage expert at IBM Deutschland GmbH, takes this view: If you want to avoid having to burn new CDs every few years, use magnetic tapes to store all your pictures, videos and songs for a lifetime."
I suppose that article was written by a public relations person and was published because someone was paid. Magnetic tapes are NOT reliable, in my experience.
In -RW media, the write layer is a metallic layer that isn't "burned" but merely heated differentially to create regions of either more-crystalline or more-amorphous metal when cooled; these regions have different refractive characteristics, and can thus be distinguished by laser. This is why it's rewritable - the melting>glassy / melting>crystalline process is reversible.
http://www.usbyte.com/common/Re-writable_CD.htm
So, to blather on only a little bit longer (too late?), to respond to the immediate contention in this subthread, the reflective layer is in NO case the very same layer as the data is written to. But, in practice, the top coating containing the reflective layer on any -R medium is so bloody thin as to make no difference. If it becomes separated from the surface of the disc, you're hosed. If you want to see how thin this layer is, stick a CD-R in a microwave for a few seconds, till it flashes, and observe the resulting flakes.
Back to the bigger question, the paragraph in this crappy article that says "The problem is material degradation. Optical discs commonly used for burning, such as CD-R and CD-RW, have a recording surface consisting of a layer of dye that can be modified by heat to store data. The degradation process can result in the data "shifting" on the surface and thus becoming unreadable to the laser beam" is needlessliy confusing things by including "CD-RW" in the statement - to conflate a REVERSIBLE phase-change/metal layer-writing process with a PERMANENT burn/dye layer write process is stupid and confusing to anyone who doesn't know better. Whose fault it was to include that, I dunno.
This still leaves the question open as to whether the sorta-stable phase-change alloy ages in substantially the same or else a very different way than the permanently altered -R ink/dye layer, and whether any such difference affects the useful lifespan. I've NEVER seen this specific question rigorously answered. I'd love to hear from anyone who has links or direct info.
I don't know about you guys, but my data always feels "warmer" when I read it from an LP-ROM. I can't explain it any better than that, you can just FEEL it, man! CDs are cold and digital, there's no love there.. Look, all I'm saying is that when I'm in the mood for some soulful gaming I bust out my copy of Quake4 on vinyl, none of this crap you'll find on CD (or worse, DVD) feels RIGHT, MAN!! VINYL FOREVER!!11 DEATH TO THE OPTICAL OPPRESSORS!!1111
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