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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."
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.
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.
... 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.
It's only anecdotal evidence, but the only CDs I have that have lasted more than 19 months or so are my Kodak Golds, the oldest of which were burned sometime in 1995. In particular, I've found any CDs that use a blue dye to be the most fragile/short-lived. However, I do live in a location with fairly high humidity (Brisbane, Oz).
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
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.
And if longevity of copies is the top priority- microfiche. Nothing beats it for expected life. It stand at close to, if not over, 100 years.
I still have more fans than freaks. WTF is wrong with you people?
I use a lot of CD-Rs for archival purposes for music on my label, LOCA records, and my experience is that stick-on labels definitely reduce the lifespan. The CD's tend to develop a noticable click when they are played in CD-players and it becomes increasingly worse as time goes by.
Conversely since I have begun using a CD pen, although it does not look as good professionally, the CD's don't seem to be developing the same fault. Now whether this is due to the fact that the CD's have come from a different manufactuer with a more recent technology - though the older ones are also from a variety of manufacturers - I don't know.
So my advice is to steer clear of CD labels and stick to pens or stamps (which is also what we use on the label now) as these do not seem to cause the same problems.
---- The Open Source Record Label : : LOCARECORDS.COM
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.
Jonah Hex
Horror & SciFi Erotic Nudes
Be careful what permanent marker you use. Some say that depending on the kind of "oil" used in the ink it can "eat" through the disk eventually.
Brand makers are even labeling some as CD safe nowadays - I'd make sure that you look for one marked as such just to be safe on any important CD's.
Here's one article I found to elaborate a little more. Mac Lab Report
Permanent markers use solvents that can easily damage CDs.
There are special water-based CD marking pens. They are both convenient and probably safe. I would guess that water-based overhead pens are probably OK as well.
I'm not an expert either, but I wanted to say that I agree about the Memorex Black line. They have been some of the best CDRs I've used. They are listed on the web site by the way. Here
What is an acceptable digital archival media?
All media degrades. The trick is to use redundant data, and re-copy it before the media is expected to fail.
And don't forget to store archival media in an archive. That's right; cool (doesn't have to be freezing, but a consistent not-warm temperature), dark, low humidity.
Non-damp basements spring to mind (as long as you don't have heating equipment in there).
You might consider sealing off CD-R media in an airtight container, such as a (zip-lock) plastic baggy of suitable quality. If it's an opaque one that locks out light as well, all the better.
If you're in the archive (basement) and need light, take care not to hit your archive media with direct light, and take care that UV light is kept to a minimum (i.e. fluorescent lighting is usually better than incandescent lighting).
It also helps to use standard 650MB CD-R media with the ISO 9660 filesystem, in stead of the latest and greatest 818 MB overburned FooFS combination.
Don't burn at 52 speed. Use media that is specced for the lowest speed you can find, and burn it at that speed or lower. You need to drink coffee anyway.
Consider tape backups. Consider a regular archiving/back-up cycle, so that if a piece of media is a dud, you'll have a duplicate from the week before or after.
Store media before use under the same conditions as you would the written archival piece. Don't buy from stores that have humid, warm warehouses.
Index and catalogue your archive. Not only will it make it easier to find things, it will also help to find or sort out duplicates - handy if you switch to a different media and re-archive your old CD-Rs on DVD for example. Archive the index as well.
Use integrity checks, such as checksums. Use compression formats that are easy to fix if a few bits go bad (e.g. no spanning ZIP archives which are useless if the last disk goes missing).
Mix lots of media, unless you're sure that what you've got is a high quality. That way, if wednesday's backup is a dud because of crappy media, the backup from tuesday might at least be better.
Once in a time, randomly check media to see that it's still readable.
Another poster asked about CD-R based RAID; you can just use PAR files (of USENET fame).
SCO employee? Check out the bounty
I check the quality of my CD's randomly using KProbe for Lite-On drives (sorry, no direct link - look for it on the net).
This tool can check the the error correction data (aka C1 or C2) stored on the CD, which is an important factor in 'how long a cd will last'. If this data contains errors, chances are high you will be left with a coaster after 2 years.
Nero's CD-speed, as mentioned in other replies, can only measure the C2 data. Plextor also released a tool that measures this data.
Other than that I now, by default, protect important data I store on CD's by redundancy. This can be acomplished by using various PAR-tools.
Depending on how much you love your data, increase the redundancy. Yes you can store less data on the disk, but with a 'simple' error you can at least hope to retrieve your data for 100%
It still doesn't hurt to burn 2 CD's though, and store them both in a safe place.
Slashdot: stuff for news, nerds that matter, matter for news, stuff that nerd
Actually you've got a rebadged Liteon, all of Sony's high speed drives are Liteon's. The good bit about that is though Sony never issues upgraded formware (with faster speeds, more formats, etc.) Liteon does and they can be tweaked so the drive still reports itself as a Sony whatever.
For downloads of tweaked firmware & flashers check out www.sonycrx2xx.org and for a list of the drives that can be upgraded check out Sony Compatability Chart. Made my $20 Sony drive a lot faster & a lot more reliable, got rid of that "hold button for full speed" sillyness.
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
It depends upon what he wants. If the extra drives are used more for backup than redundancy, then a nightly cron job would likely be best. That way, there is a chance of recovery from files that are accidentally deleted during the day.
To be more paranoid, he could have a live RAID 1 in the computer with a third, hot-swappable SCSI drive used for the backup drive. That way, the swappable drive can be stored in a fireproof safe during the 23 hours it's not plugged in.
Sanford has used SHARPIE markers on CDs for years and we have never experienced a problem. We do not believe that the SHARPIE ink can affect these CDs, however we have not performed any long-term laboratory testing to verify this. We have spoken to many major CD manufacturers about this issue. They use the SHARPIE markers on CDs internally as well, and do not believe that the SHARPIE ink will cause any harm to their products.
If it were an issue you can bet Sanford would be covering their ass legally and not making such a claim.
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.
Backing up separately has advantages over RAID. First, RAID won't help against accidental malicious deletion, whereas a separate backup will. Second, RAID would hurt performance if you're using a slower (cheaper) hard drive for backups. Third, you'll need a lot more storage with RAID, because your 'backup' isn't compressed. Fourth, incremental backups.
The following things are known to adversely affect CD-R life:
- Application of anything to the CD-R surface that is soluble in the plastic (generally polycarbonate) medium that constitutes the disk. This includes label adhesives and inks. One thing that is definitely safe is water based formulations such as what is used in the CD marking pens sold by TDK. I have personally seen enough CD-R's marked with Sharpies fail to never want to use these markers on a CD-R.
- Direct exposure to sunlight or exposure to temperatures above 40 C. With some of the crappier dye formulations out there this can lead to failure in as little as 1/2 hour.
- Use of poor quality media. Princo and other Tiawanese based CD-R manufacturers have a very bad track record. The best media is based on a gold stabilized dye formulation invented and sold by Mitsui. Kodak was a licensee of this until they got out of the CD-R manufacturing biz. (The only way you will get my cache of Kodak Gold media is by prying it out of my cold dead hands.) Kodak published estimates of 200 year lifetimes for it's Gold Ultima media. Mitsui is the same chemistry and should work just as well. I have never seen a Kodak Gold CD-R fail, including after having been left on a car dashboard in direct summer sunshine. Generally media manufactured in Japanese plants is usually ok for normal use. Be careful - outfits like TDK, Fujifilm etc. sell from several sources. Buy the ones made in Japan, not the ones made in Taiwan. For critical stuff like family pictures, tax data, etc. go for the gold.
... and UV filters are available for florescent bulbs, just in case you need them.
BTW, the high brightness halogen incandescent bulbs do emit UV light, but not the standard coated, screw in bulbs; and florescent bulbs dump a shitload of UV out at the ends, where there is no coating.
I work in a darkroom, around things that are very UV sensitive. Someone taking a flash picture nearly had his head mounted on a pike by the door this week!
Truth isn't Truth - Guliani
Firstly you should obviously be using high quality discs. Those cheapies will die quickly. Get ye some Taiyo Yuden, Memorex Black, TDK or similar.
Note that there are only something like twelve companies in the world that manufacture CD-R discs and then the brand name of many other companies are printed on them. For example if you find FujiFilm CD-R spindles that say "Made in Japan" then they're probably TY. This is what I use religiously. (Note: Some Fuji is made in Taiwan by Ricoh as well. You're safe to ignore these ones.)
Use a good physical storage method. This means that both the front and back of the discs are protected. Honestly I find that the Microsoft's Technet binders offer the best security and disc density in this field. The little sleeves are modular and the binders have rings so you can open the binder, hand the disc WITH THE SLEEVE to the next person and avoid getting fingerprints or dirt the disc. A lot of other binder sleeves leave half the disc exposed so they're rubbing against each other and so on. This is bad. You want the front and back of the disc to be protected completely.
I also put a little silica gel pack in my CD-R binders although honestly I have no systematic evidence that this helps control the humidity and makes a difference in the discs' longevity. But I'm better safe than sorry. (I basically collect the packets when I open the boxes from new computer products. At one job I had I opened a lot of new products so I collected a lot of the packets.)
I use a water based marker to label all my discs. No glue-on labels or alcohol based markers to eat through the discs. Now admittedly there are lots and lots of cases where people use sanford sharpies (which are alcohol based) and have NO bad side effects. Many of my older discs are labelled with sharpies and only ONE out of hundreds has failed, and there's no evidence that the sharpie was directly related. Still, you can't go wrong with a pack of 4 memorex water based CD-markers for $3. The only downside is that sharpies give you a daker, finer ink stroke.
And if your data is really that important, I hope you're not burning only one disc. Burn 3 and keep them in different physical locations so if one disc is lost to theft or file or decay, your data is not instantly lost.
Use 10% of your CD space for PAR2 files. Then as long as you have semi-intact files and enought 'blocks' in your PAR2 files to repair them, its like having RAID 5 on a cd. What you could also do is for every 3-5 cds you burn, burn a cd that contains JUST redundancy data, a-la PAR2. This is like raid 3 on cd.
It depends on howmuch you care about your data, but this way, you could lose any one of those 3-5 cds and replace all the data, good as new.
Here is the PAR2 Spec for the many software nerds out there.
And here is Quickpar, a good PAR2 makeing tool.
It's easier to fight for one's principles than to live up to them.
Reburned them for archival copies. 12 Discs - No errors. Never used labels (always figured they were dodgy), used water-soluble ink marker. No Sharpie!
They are some of the oldest mp3s in my collection! Also kind of nostalgic reading through 10-year-old NFOs from cracker groups long past.
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