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CD-R Lifespan - Is It The Label?
sysadmn writes "Slashdot has discussed archival lifespan of CD-R media before. Fred Langa revisits the issue with a new twist: Are glue-on labels causing premature failure? Much more common than rain forest fungus! From Fred's informative LangaList newsletter."
...but I've stopped doing that. For one thing, humidity causes the clue to come off, leaving you with a bubbly cd that doesn't fit in many slot cd players (esp. car players). Dragging the label off at this point will damage the cd.
What kind of protection do normal music CDs have to avoid this kind of rapid degradation? Is there any?
I haven't personally had any CD-Rs go bad on me, but I know a few people who have old CD-Rs that are unreadable in current devices. We chalked that up to a difference in formats, but it may have been this problem.
What is an acceptable digital archival media?
To demonstrate the durability of CD-R media, my ex-roommate once licked the active side. I hope neither the dye nor the plastic is toxic. But since I was always suspicious my roomie may have had a few screws loose, that may not matter too much.
Stay sentient. Don't drink bad milk.
A co-worker turned me on to Fred's column a couple of days ago, and I've been running a few tests that may or may not have a bearing on reality...
The cheap-ass CompUSSR CD-R with and without their corporate logo were the main object of testing.
In a nutshell, the pre-printed logo CD-R survived the label removal much better than the generic no-name blank did, though you _could_ screw up the printed one just as badly with a little effort.
We're going to get everyone in the office to offer up a sacrificial CD-R of choice to conduct more tests, and I will also introduce my co-workers to the Round Table Rate-A-Record system with the office microwave...
Then we'll see what happens to DVD-R/+R...
"Eustace? Eustace? Are you there? Are you there?" = John Leeming
I upgraded (if you call it that) from a plextor 16x to a sony 52x (really 48x). Compusa had 52x Sony media on sale for 30 bux for 100, figured it was a good deal, and would burn well on the Sony drive. Worst media I ever had, 48/32/16 burns would create coasters, and the media also would fail at 16x on the plextor. The media Did work at 4x-1x, so I used 4x and tossed about 40 bad ones in the garbage.
I also noticed the CD's had a static on them, when stacked, they would stick to each other, not a good coating on them either, and Memorex 48x that I bought was a little thicker, did not have any static on them. Seemed more like pressed CD's.
Not very techinical, I just know that the Sony brand was not top quality, and it felt cheap. So I wouldnt be surprised that some media dies after awhile due to air, etc. And slower burning did work on the media, so I guess burning at 1x on junk media would make it last longer, but who knows how much longer that is.
I just wish there was some technical reviews on media, thickness, quality of materials, burn speed test, tested with multiple media. Now I'm having the same problem with DVDR's, they are now 99 bux for a 4x drive, and half the media I buy only burns at 1x.
Bulk Media for DVDR's seems to also offer the "cheapness" now. I just wish there was standards, or some way of know my data was safe, other than making copies every 2 years. And trying to save a buck per disk doesnt seem to be helping the quality I purchase.
Of the CDs I own, the ones that've gone bad have suffered damage to the top foil part. It either rubs off, or partially becomes dislodged from the bottom part. All the review sites seem to think the dye is the weak link in the chain, but in my experience a crapy foil will go long before the dye.
AccountKiller
I've bought many brands of CDR's over the years from Sony, Pioneer, TDK, Mitsui, Kodaks, Laser and all have worked fine for me.
TDK gets somebody else to makes their discs and I've gone through a few different TDK-branded disc coming from differenet factories and I haven't had a reliabilty problem with any of them. Mitsui and Kodak golds are my favourties but they're hard to find now. Lasers are cheap and havent had any problems using them. I had some issues with Imation discs, the label side developed a yellow tint before becoming unreadable soon afterwards.
I've had lots of problems with no name brands. CRC errors galore after a few months despite me keeping them out of the sunlight (or room light) in the filing cabinet along with all my other CDRs.
Most of my coasters are from burn failures due to my fault, buffer underruns when I had my old computer, and the dye disapearing. I've never had a problem from scratched cdrs or the label side peeling off but then my use of cdrs is usually to burn them to disc and then stuffing them into my filing cabinet until I need to reghost my HD.
I used to buy cheap bulk no-name CDs. However, about 1 year later, the aluminum coating was flaky and fell out of the CD... So, when you can see the light through the hole from the fell-out coating... So, the CD breaks.
In this case, coating it would have helped. I dunno whether it would end up the same way as stated in the article, though.
But, if you can spend more money on CD-Rs, you'd be better up with branded CD-Rs and apply no labels.
--
Error 500: Internal sig error
here is an easy solution that has worked for me for years. 1. get a perm. marker 2. label your cd-r "applications cd1" or "music cd1" 3. make a text file(html format works the best) list contents of each cd-r 4. done simple as that no wasted time trying to make labels.
All media degrades. The trick is to use redundant data, and re-copy it before the media is expected to fail.
Is there a way to detect when a CD is about to fail? The CD drive will auto-correct minor errors without informing the PC - so by the time a drive returns an error code, at least one block of data is lost (if you're lucky, you can copy everything else off the CD).
I'm aware of commercial testing hardware that can report statistics like the Bit Error Rate (BER), Block Error Rate (BLER), etc. But is there any way to do this cheaply, possibly using software?
I have noticed that on some of my CDR's, burning slower results in a different color than a faster burn. I guess the dye is being changed more when it is slower. So now, for CD's that I want to keep for a few years, I write them at 4x even though I have a 48x burner. As for the labels, I don't use them.
... is the major reason for my failed CDs.
I've only used brand name CD-Rs, my all time favourites are Kodak Golds. Unfortunately they're not making them anymore, because the process was far more expensive than the regular blue or green dye one. But with the Golds I never had a coaster, and all the ones I kept since 4 years ago still work. Other brands I had luck with were Maxwells and TDKs, but they don't look as nice as the Kodaks.
I also keep them protected in some way, either in sleeves, jewel cases or spindles.
The only CDs that ever failed were Hi-Vals. They were the first spindle I ever bought, and even out of those, only one died completely. The paint just peeled off the CD, and it became unreadable. But that CD saw a lot of abuse, sitting in my car for 3 years through very hot, humid summers and frigid winters in Toronto.
Overall, I agree with the article, a bit of prevention will preserve CDs for a long time, probably untill the data on them has become useless.
Considering how cheap hard drives are now (about $100 for a 150G disk) it's better to buy multiple hard disks to back things up.
I've decided that if I want to back up my important media for my business, I am going to make a storage machine. Basically it will be a low end machine with a fast network connection and a lot of hard disk space. Each night when I want to back things up I'll send all the files over to the backup machine. To be extra safe I would double the drives in the machine and setup a chron job to copy files from one disk to the other and mirror the drives. That way if one physical disk fails, the files are backed up on another. Also, I'd give it a wireless connection and put it on a very well surge protected power strip. That way lightening is less likely to get to it. Yes, call me paranoid, but I've lost so much data due to media failure that I don't take the risk anymore.
Outdoor digital photography, mostly in New Engl
Part of an email from a friend who is on a small boat somewhere in PNG:
Among other adventures, the boat was broken into while I was alone on
board. Not much stolen, but my MP3 collection was immersed in sea water
before being recovered and I was most disappointed to find that many of
the CDs didn't like the experience. It looks like water got in between
the layers of laminate and dissolved the ink. TDK CDs were the worst.
Now you know.
Ceci n'est pas une signature
We need to worry. REALLY. I am burning a cd right now. The data is music. Music from about 25 years ago that was on a reel to reel (older tape analogue) that had to be baked (put in an oven to recover the lost footage more here: http://www.soundsaver.com/squealingtape.htm)
If I am burning this to CD and then the CD becomes faulty, which is likely from my experience, the CD becomes useless, there is no turning back. This has happened to me, a skip becomes more and more of a skip until unplayable.
CD's are not a good way to archive anything.
Fuji is advertising 70-100 years.
I was given some cheap disks that were labelled with some kind of permanent marker. They worked fine then. A couple of years later I was looking for a file that might have been on them and found them largely unreadable. Looking at the actual disk from the bottom I can see the metal layer is completely gone directly below the ink (which has itself faded, or maybe sunk into the disk.
I had a similar experience (or so I thought at the time). About 50% of a spindle of cheap 10x CD-RW's simply failed even after repeated attempts to blank and reburn them. Fortunately, I threw all the CD-RW's that failed into my coaster pile rather than the trash, since about a year later after I had replaced my CD burner I discovered that every single one of them worked fine.
The failing burner was a Yamaha SCSI unit that I paid about $200 for four years ago; it was (and probably still would be) quite reliable with other media, but it was only a 24x8x8x unit, which is why I replaced it. Its replacement, a Sony 48x24x48x IDE unit (rumored to be a rebadged Liteon), cost $50 on sale. It, too, seems to work with everything I throw at it -- including those CD-RW's the Yamaha couldn't deal with.
I suspect that drive/media incompatibility is more common than most people think. Some reports of failing media may be due to media that was marginally recorded to begin with due to such incompatibility.
but i have learnt a few things!
- don't let cdrs touch each other ever. they *will* scratch each others data off. never put written cdrs on spindels or two to a slot in a case. i was too cheap to buy another case and immediately b*gg*r*d some of my discs stickin em two to a slot w/ a grain of sand in between!
- if you have to put a cd down not in a case, put it play side down. i've seen people put them label suide down thinking its 'protecting the disc' - worst thing you can do. a scratch on the plastic side ain't so serious, you could maybe polish it out in a pinch
- overprints are good, if you can get them. these are discs where the original label was printed wrong and has been.. overprinted. = cheaper AND tougher in my experience :)
- writing on a disc with soft tip permanent marker (you dont have to buy "cd markers", thats a joke) has never caused me a problem. i think labels are asking for trouble, but ive always been too cheap to try them :p don't use a hard tipped thing eh in case anyone is stupid to try a biro or sommat
- some cds are just sh*t and fall apart no matter what you do! if data is really vital i'd get two stacks of diff. makes of media and burn two sets (of course, im never sensible enough to do this)
- use the verify funtion of your cdr app if you're not in a hurry. then you know at least the disc started out alright.
there's probably loads more things i'll think of after posting this eh.
the biggest problem i have is with some cds developing mysterious "spots". there is a little speck with a discoloured ring around it, that can fall off, but even if it doesnt the disc is ruined. anyone have any idea what it might be that's touching my discs and doing this to them? i'd love to know, 'cos im stumped. id post a picture of one of these if i was somewhere with a scanner.
oh yeah, did i mention i was cheap! :p maybe buying more expensive blanks would help some of my problems, but i suspect you don't get what you pay for necessarily.
This is my Sig, this is my Gun. One is for Slashdot and one is for Fun.
Large batch produced CDs (such as music CDs, AOL CDs etc) are manufactured by stamping the CD pits into a thin layer of aluminium. This is then covered in plastic to protect it on the bottom and a layer of ink on the top. There is no dye layer to degrade with time.
CDRs have a blank die layer into which the CD writer burns the pits. This dye layer is what is causing the problems for long lifetime.
wot no sig
I have a hard time believing this. I've had some CDR archived materials for 5 or more years that read fine. I think the bigger problem is clueless users (like I used to be) who mistakenly burned CDR media at a speed too high for what the media is rated for. Those discs seem to run fine at first, but then die later. I've lost several gigs due to this problem just because I know how I used to burn CD's.
You are correct on the method of manufacture, but the aluminum layer is still subject to oxidation. If the polycarbonate layer is cracked, split, perforated, or otherwise damaged or defective, moisture can reach the surface and corrode it.
As a reliability engineer, I can tell you that the long-term longevity of manufactured materials is driven (a) by process characteristics (i.e. is there a manufacturing flaw) and (b) thermodynamics. Diffusion processes and chemical reaction rates are all driven by temperature.
If you want your CDs or CD-Rs to last forever, store them below 5 degrees Kelvin or so. You can immerse them safely in liquid helium, it's inert. Make sure it doesn't go superfluid on you, and climb out of the Dewar and away from your 'Britney Unplugged' sessions.
Check out the freeware win32 tool Nero CDSpeed which has many excellent functions for measuring the quality of optical discs (CD, CD-R, CD-Rw, DVD, etc) and tools for verifying the integrity of stored data. Its scandisc function test the drive's ability to read each file at the filesystem level and read each sector at the physical level, telling you which sectors are good, which are failing and which are dead.
An interesting side effect of using this tool is that I've noticed that the manufacture of pressed DVDs is highly variable! Some discs are excellent, some are crap. And it seems to be pretty consistent with the company that distributed them too. Some discs read very smoothly while others require all kinds of speed adjustments by the drive to get data out of them.
Some discs read very smoothly while others require all kinds of speed adjustments by the drive to get data out of them.
getting data out of DVDs? the data is supposed to stay in them! You are in violation of the DMCA. please turn off and step away from the computer and wait calmly for Ashcroft to arrive in a fleet of black helicopters
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