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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."
I have some CDs that are burned copies (although I'd call this great quality cds, not cheap storebrand with no backing), stored in a CD wallet case that are easily over 5 years old... still work great.
Starmen.net
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've mulled this occasionally, but I suspect the late 20th century and early 21st century will become a mini-dark ages (at least for personal or family things).
The reasons for this:
1. depressingly high failure rate of hard disks
2. lack of long term storage media
3. obsolete formats
As for tape, DLTtape (invented for the venerable VAX) is supposed to be able to last 25 years in good condition. How many people buy DLTtape drives? They aren't cheap and the tapes are not cheap. They are about the only thing with the capacity to store all your photos and video on one cartridge.
Digital photos and video seem like great things (and are: I'd hate to have to edit my videos the old fashioned way) but there is a sting in the tail that most people won't expect. If I want to look at a photograph my Dad took in 1972, I just pull it out the draw and look at it. No maintenance has had to be done on that photograph - it's just been stored in a cool, dry, dark place.
Digital data on the other hand needs periodic maintenance. If a format you've used becomes obsolete, you have to go through and update your entire library. You have to periodically back it up. You have to periodically cut it to media like CD. How much family history have people lost already due to dead hard disks, and not realising the need to continuously back up and format shift? Even if a DLTtape cartridge is still intact and readable in 75 years time, will there be anything to read it? Will JPEG decoders come with everyone's device to view photos?
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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.
Yeah, except that seek time would really suck -- no matter how quickly you could pick up and move the tonearm.
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.
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.
Have your army of minions engrave all your really important data on clay tablets. Then try to make sure the tablets are stored in the basement of your palace when it burns to the ground, so the clay gets well-fired. Thousands of years from now, archaeologists will marvel at your beautifully preserved backups. They'll call it "cuneiporn."
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
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.
This thread also strikes me as funny because I'm in the middle of archiving about 800 VHS tapes to DVD. Many are 15-20 years old, and I've been surprised at how well most of them still work. I wonder if the DVDs will last as long, but I figure it'll be easier to move the data off them since it won't have to be done in real time.
1) Burn 2 copies, store them in physical separate locations.
2) Don't fill the discs to the brim. Only encode about 3.8-4.0GB of MPEG2. Fill the rest of the disc with PAR2 files stored in the VIDEO_TS folder (prefixed with the letter 'z' so they appear on the edges/end of the disc).
I render my DVDs to disc first, add the PAR2 data, then create the ISOs with ImgTool Classic before burning to disc. I make sure that my block size for PAR2 is a multiple of 2048 bytes (CD/DVD sector size).
Even if you can't copy individual files off of the disc, tools like ISO Buster or ddrescue (or dd-rescue) can read the disc back at the sector level. That lets you pull as much information as possible back off of the disc. Assuming you don't have more bad sectors then recovery data, QuickPar (or the open-source commandline tool) can chew on that extracted data and rebuild the files.
I did about 100 VHS tapes a year or two ago. I still have a bunch more to do in the coming year.
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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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Gold reflective layer CD-R's with a stabilized pthalocyanine dye have an expected shelf life of 200 years.
That's 4 times longer than the expected life of an aluminum reflective layer pressed CD.
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