Interesting article on 'CD rot'

[mdwatts]

A friend at work just sent me this. Found it interesting, so thought I would post here.


CHARLOTTE, N.C. — Dan Koster was unpacking some of his more than 2,000 CDs after a move when he noticed something strange. Some of the discs, which he always took good care of, wouldn't play properly.

Mr. Koster, a Web and graphic designer for Queens University of Charlotte, N.C., took one that was skipping pretty badly and held it up to the light.

"I was kind of shocked to see a constellation of pinpricks, little points where the light was coming through the aluminum layer," he says.

His collection was suffering from "CD rot," a gradual deterioration of the data-carrying layer. It's not known for sure how common the blight is, but it's just one of a number of reasons that optical discs, including DVDs, may be a lot less long-lived than first thought.

"We were all told that CDs were well-nigh indestructible when they were introduced in the mid 1980s," Mr. Koster says. "Companies used that in part to justify the higher price of CDs as well."

He went through his collection and found that 15 per cent to 20 per cent of the discs, most of which were produced in the 1980s, were "rotted" to some extent.

The rotting can be due to poor manufacturing, according to Jerry Hartke, who runs Media Sciences Inc., a Marlborough, Mass., laboratory that tests CDs.

The aluminum layer that reflects the light of the player's laser is separated from the CD label by a thin layer of lacquer. If the manufacturer applied the lacquer improperly, air can penetrate to oxidize the aluminum, eating it up much like iron rusts in air.

But in Mr. Hartke's view, it's more common that discs are rendered unreadable by poor handling by the owner.

"If people treat these discs rather harshly, or stack them, or allow them to rub against each other, this very fragile protective layer can be disturbed, allowing the atmosphere to interact with that aluminum," he says.

Part of the problem is that most people believe that it's the clear underside of the CD that is fragile, when in fact it's the side with the label. Scratches on the underside have to be fairly deep to cause skipping, while scratches on the top can easily penetrate to the aluminum layer. Even the pressure of a pen on the label side can dent the aluminum, rendering the CD unreadable.

Mr. Koster has taken to copying his CDs on his computer to extend the life of the recordings. Unfortunately, it's not easy to figure out how long those recordable CDs will work.

Fred Byers, an information technology specialist at the National Institute of Standards and Technology, has looked at writeable CDs on behalf of government agencies, including the Library of Congress, that need to know how long their discs will last.

Manufacturers cite life spans up to 100 years, but without a standardized test, it's very hard to evaluate their claims, Mr. Byers says. The worst part is that manufacturers frequently change the materials and manufacturing methods without notifying users.

"When you go to a store and buy a DVD-R, and this goes for CD-R as well, you really don't know what you're getting," he says. "If you buy a particular brand of disc, and then get the same disc and brand six months later, it can be very different."

This renders the frequently heard advice to buy name-brand discs for maximum longevity fairly moot, he says.

DVDs are a bit tougher than CDs in the sense that the data layer (or layers — some discs have two) is sandwiched in the middle of the disc between two layers of plastic. But this structure causes problems of its own, especially in early DVDs. The glue that holds the layers together can lose its grip, making the disc unreadable at least in parts.

Users who bend a DVD to remove it from a hard-gripping case are practically begging for this problem, because flexing the disc puts strain on the glue.

Rewriteable CDs and DVDs, as opposed to write-once discs, should not be used for long-term storage because they contain a heat-sensitive layer that decays much faster than the metal layers of other discs.

For maximum longevity, discs should be stored vertically and only be handled by the edges. Don't stick labels on them, and in the case of write-once CDs, don't write on them with anything but soft water-based or alcohol-based markers.

Also, like wine, discs should be stored in a cool, dry place. Mr. Koster's friend Mark Irons, of Corvallis, Ore., stored his CD collection in a cabin heated by a wood-burning stove. The temperature would range between 40 degrees and 70 degrees in the space of a few hours. Now, the data layer of some of his CDs looks as if it's being eaten from the outside.

Mr. Irons is still pretty happy with CD technology, since it beats vinyl LPs and tape for longevity. Now that he's moved his discs to an apartment with a more stable temperature, he's noticed that the decay has slowed.

"I'm hoping they'll hold out till that next medium gets popular, and everyone gets to buy everything over again," he says.

[hard candy]

Oh great, now something else to worry about. :(
So I guess the solution is to copy 1980"s and early 1990"s cds to newer medium. But wait, in the USA that would be illegal.
So now the choice is break the law or have invisible termits eat your cds.
My parents told me that "awful music will rot your brain" but they never mentioned cds. :D

[gehidore]

So thats why my eight original first release of several beatle albums on cd are ruined?

houses with wine cellars and cd cellars? insane.

whats up with these names?


Dan Koster > broken cd = coaster?
Mr. Hartke > i dont have to say.
Fred Byers > Fred Buyers? buying things..
Mark Irons > i dont want to say.


subliminal messages?

[gehidore]

Originally posted by hard candy
... have invisible termits eat...

termits never heard of them, do they taste good?

;) ;)

[Icarus]

Originally posted by hard candy
My parents told me that "awful music will rot your brain" but they never mentioned cds. :D Pantera fan, eh? :)

I find a lot of talk about "CD rot" to be bogus, but then again I handle all my CDs with care and don't do stupid things like lick the non-lable side after drinking a can of Coke-Cola and then try playing them...or leave them sitting on the dashboard of my car and wonder why they make a weird noise from the player when I play them :D

I have music CDs from the 80's that work just find (even ripped them recently) and data CDs from '97 that are fine (even on crappy no-name disks)

Just treat them like they are fragile and they will last, just like everything else.

[cybertron]

Old news, I've known that CD's (especially burned ones) die after a certain period of time for a while now:) It happens all too often to me:rolleyes:

[Parcival]

CD rot is one of the reasons why professional archives (e.g. governmental ones) are hesitant to backup data digitally for the generations still to come. According to the curator of the State of Bern paper still is the safest way to archive information for a long time - all you gotta make sure is that it's stored in a dry spot...

[rocketpcguy]

cybertron: this is worrying! how long does it take to get damaged?

[mdwatts]

Originally posted by Parcival
CD rot is one of the reasons why professional archives (e.g. governmental ones) are hesitant to backup data digitally for the generations still to come. According to the curator of the State of Bern paper still is the safest way to archive information for a long time - all you gotta make sure is that it's stored in a dry spot...

I'm gunna start copying all my cd's to paper right away.

[cybertron]

Originally posted by rocketpcguy
cybertron: this is worrying! how long does it take to get damaged?

Depends on how you handle them. The people I know who just throw their cds around tend to be burning new copies a lot. I've only had one or two cdr's die on me (skips, not so much what is mentioned here) in probably 5 years, but my experience with cd-rw's has been less than pleasant. I lost part of a hard drive backup because my cd-rw died. I'm really careful with them too. I always hold them by the very edge and don't touch the data side.

I did find it very interesting that it's actually more important to take care with the label side than the burned side. I thought it was scratches on the burned side that caused problems, but now it makes me wonder if it isn't the other way around. I also wish that DVD manufacturers would put the discs in a decent case that doesn't require a pliers to get them out. It seems like a lot of them want you to have to flex the disc to get it out, which according to the article is really bad. Maybe I'll throw out the cases and keep them in a cd wallet like I do most of my CD's. Ah well, I'll just have to keep vigilant with my disc handling:)

[cybertron]

Originally posted by mdwatts
I'm gunna start copying all my cd's to paper right away.

LOL! I'm sure my distro cd's will restore very well from paper if the discs go bad:D

[mdwatts]

Originally posted by cybertron
LOL! I'm sure my distro cd's will restore very well from paper if the discs go bad:D

I'll still use the original audio/data cd's for listening and installation. The paper copies are only in the event something happens to the cd's.

[hlrguy]

Originally posted by mdwatts
I'm gunna start copying all my cd's to paper right away.

You get my vote for the funniest comeback of the week. Actually put coffee out my nose.

hlrguy

[Icarus]

Originally posted by mdwatts
I'm gunna start copying all my cd's to paper right away. Looks like Mike's back on his medication :eek:


I'm off to print out the entire 2.6.6-rc1 kernel source now, just in case!

[mdwatts]

Oh good lord... Now I'll have to get one of those high speed scanner things just for emergencies. Or should I live on the edge and just hope my cd's never rot? :confused:

[cybertron]

Maybe we could go back to using punch cards? Weren't they made of paper (I'm not old enough to know:) )?

[hard candy]

I can see it now:
"I'm hoping you all can help me, I'm trying to restore my RH9 installation but seem to have a lot of problems. The first is that I have a real hard time getting all the paper that has the installation disk printed on it in the cd player slot And the second is that even though I choose "linux text" as the boot option my paper is still not read. Do you think maybe I got a CD player that cannot read English? Is there a translator for those things?"



termits never heard of them, do they taste good?

Termit- a small green termite who is on the Muppit show.

[gehidore]

Originally posted by hard candy
Termit- a small green termite who is on the Muppit show.

i never knew, ive never seen the muppets, but ive also never seen the little mirmaid....

now when im on one of those game shows ill know the answer to what color is the character termit from the muppets?

[JayMan8081]

Everyone must be in a witty mood today. The comebacks are flying fast and funny on here.

[heckle]

I think I may try running all of my cd's through the xerox machine at work tomorrow so that I have an extra copy. Anyone else wants copies? :)

[dboyer]

I remember when my dad first saw my linux box.. "command line huh? just like our 286!"

...

I can't imagine the **** i would get if he caught me installed linux off of a gazillion punch cards...

linux - a blast to the past!

[bwkaz]

Originally posted by cybertron
I thought it was scratches on the burned side that caused problems, But on a CD-R, what you call "the burned side" (the side that changes when you burn the CD-R) is actually stored on the top of the CD-R (directly below the label, if you put a label on it), not on the bottom. That's what many of the comments in this article were saying.

Take a (blank!) CD-R sometime and scrape a car key (or something else with a sharp edge) across the "label" side. The extremely thin foil layer (the layer that changes when the disc gets burned) will flake right off, leaving you with a worthless 1/16th-inch thick (or thereabouts) piece of clear plastic in a circular shape.

The data is stored on the "label" side.

[GigaShadow]

This puts an entirely new spin on the term "ripping a cd"......however, com - piling paper might be a bit more difficult....


G :D

[blobaugh]

Man, it's sure gonna take me a while to write down all those 1 and 0s!!

[glasdave]

Seems like being ambidextrous would bode well then:D

[sploo22]

I'll just print out the lyrics to all my songs. 500:1 compression ratio, and they're still perfectly understandable! Beat that, Ogg! :p

[Sepero]

Originally posted by bwkaz
But on a CD-R, what you call "the burned side" (the side that changes when you burn the CD-R) is actually stored on the top of the CD-R (directly below the label, if you put a label on it), not on the bottom.No SH**!?!? :p
That's the cooIest crap I've heard in a long time! I never knew that. Has anyone on here ever recovered a TERRIBLY scratched up(on the plastic side) CD???

[bwkaz]

I've never done it, but supposedly a bit of wax (basically stuff like car wax, though I wouldn't use car wax itself) can fill in deep scratches on the plastic side and make the CD usable again.

[keyshawn]

Originally posted by bwkaz
I've never done it, but supposedly a bit of wax (basically stuff like car wax, though I wouldn't use car wax itself) can fill in deep scratches on the plastic side and make the CD usable again.

I also heard that toothpaste works as well too, but i never tried [could be just a rumour.]

[Seven up]

I have actually used toothpaste on a win 2000 cd that my buddy had been less than carefull with it would boot but would crash 1/4 way through install. The scratches weren't terrible but bad enough I guess. I have use the disk several times since with out a problem and as a plus it smells minty fresh. :D

P.S. you want to use small circles and start from the inside and work your way out, and of course rinse it off very well.

[cybertron]

Originally posted by bwkaz
But on a CD-R, what you call "the burned side" (the side that changes when you burn the CD-R) is actually stored on the top of the CD-R (directly below the label, if you put a label on it), not on the bottom. That's what many of the comments in this article were saying.

Take a (blank!) CD-R sometime and scrape a car key (or something else with a sharp edge) across the "label" side. The extremely thin foil layer (the layer that changes when the disc gets burned) will flake right off, leaving you with a worthless 1/16th-inch thick (or thereabouts) piece of clear plastic in a circular shape.

The data is stored on the "label" side.

I had sort of noticed that before, but I never gave any real thought to it. On a couple of the cdr spindles that I've bought there was a cd without the foil part, I guess to take up space or something, and I did notice the similarity, but I had thought that the foil was just to reflect the laser or something. It's amazing what you can learn outside of the classroom:)

[Sepero]

FREE Scratch Removal System
http://www.btinternet.com/~zturner/chapter1.htm

[hiwa]

For public resources, there are many copies on the net.
For private/personal ones, if they are very important, I use multiple storage sites.
For others, accept whatever happened to them. Still we/you can live without them.

[blobaugh]

If I have anything of true importance I have it backed up on multiple different media sources anywho.

Cool toothpaste idea, I never would have thought of that

[hard candy]

Cool toothpaste idea, I never would have thought of that

"he mint to fix that cd". :)

[Sepero]

Originally posted by blobaugh
Cool toothpaste idea, I never would have thought of that Now his CD is in Mint condition.

[Pierre Lambion]

Actually, copying CDs on paper might get possible:

"TOPPAN and Sony Successfully Develop 25GB Paper Disc
Blu-ray Disc technology-based paper disc to be unveiled at ODS "
2004http://www.sony.net/SonyInfo/News/Press/200404/04-0415E/

P.

[Sepero]

Originally posted by Pierre Lambion
Actually, copying CDs on paper might get possible:Man, that's pretty cool! This thread just keeps getting better!

Environmentally speaking, this does sound better than the 'aluminum/plastic' discs we use now. <fingers crossed>

Also, they need to start putting storage in back into cases! All this about, "Ooops, I scratched my DVD." is CRAP! I never had that problem with floppies, vhs tapes, or cassettes. (although, floppies would sometimes die on their own)

[Icarus]

Never heard the toothpaste treatment before? It contains fine grains that gently scrapes the plastic down 'removing' the scratch (by removing the plastic around the scratch)

This is the same way those "CD repair kits" work, they just don't have that minty taste! :D

[hlrguy]

Originally posted by mahdi
This is the same way those "CD repair kits" work, they just don't have that minty taste! :D

And you know for a fact that it doesn't have a minty taste? Were you the kid who ate all my glue in the 3rd grade?

hlrguy

[mdwatts]

Originally posted by mahdi
Never heard the toothpaste treatment before? It contains fine grains that gently scrapes the plastic down 'removing' the scratch (by removing the plastic around the scratch)

This is the same way those "CD repair kits" work, they just don't have that minty taste! :D

One of the Discovery channel shows had a segment where they demonstrated one of the 'CD repair kits' and also mentioned the cheap method of using toothpaste.

They both work quite well for minor scratches.

[gehidore]

Originally posted by Sepero
Now his CD is in Mint condition.

not only is it in "Mint" condition but now it will make a gread desert or appetizer (that is tooth friendly) for you guests!:rolleyes: :rolleyes:

[Icarus]

Originally posted by hlrguy
And you know for a fact that it doesn't have a minty taste? Were you the kid who ate all my glue in the 3rd grade?

hlrguy No I never ate glue...hate the smell of the stuff!

But you did catch my earlier comment about licking the CD with Cola Tounge and playing it, right? :p

[rocketpcguy]

i want to backup my CDs. can someone tell me what DPI i should scan them with to get those 0s and 1s?

[blobaugh]

I don't think any of our current scanners are capable of capturing all the 1 and 0s. I have heard reports of a new one in beta that comes close though;)

[hard candy]

I was thinking, if you can use toothpaste to fix newer cd's, and the original story was about cd's becoming flakey, why not use denture adhesive to keep the flakes from peeling off? You know like Fixodent? Even the name fits- "Fix" "o" "dent" is appropriate. Heck it would probably work on cars, too.
The trouble with paper cd/dvd disks as proposed by Sony is that people would get shot. We older people would tell our granchildren we were going to burn cd's and they would shoot us to protect their music collection. :)

[mdwatts]

Originally posted by rocketpcguy
i want to backup my CDs. can someone tell me what DPI i should scan them with to get those 0s and 1s?

The higher the better which will then be less prone to media read errors.

If you ever need to use for restoring, you should get one of those high speed paper feeders that also can hold 500+ pages or else your arm will get mighty tired.

[Arjay]

A few months back i was gonna post and ask if anyone knew why some of my CDs had pin pricks size holes in them when held up to the light. I noticed this when i was installing a program and it failed half way through. The CDs where approx. 4 years old.

Well now i know..

Cheers

[Icarus]

Originally posted by Arjay
A few months back i was gonna post and ask if anyone knew why some of my CDs had pin pricks size holes in them when held up to the light. I noticed this when i was installing a program and it failed half way through. The CDs where approx. 4 years old.

Well now i know..

Cheers Scotland, eh? It could've been the CD eating Fungus (http://news.bbc.co.uk/1/hi/sci/tech/1402533.stm)
(and no, it's not a joke)

[The Linux Kid]

For backing up your cd's to paper, look in Google for a neat little program called PaperDisk...

Very interesting....

I still don't see any use for it though.....


The Linux Kid

[Arjay]

Scotland, eh? It could've been the CD eating Fungus
(and no, it's not a joke)

Hmmm....Interesting, my Brother-in-law was in Belize a few years ago and used to sleep in this room. Maybe he brought the CD eating fungus back with him.

Well at least now i have someone to blame...

Cheers

[rocketpcguy]

protect your CD's by placing MS windows cds and Visual basic CD's around it, this way those fungus would lose their appetite.

[raz0rblade]

Time to back up all my cd's to paper. :)

cat /dev/cdrom0 > /dev/lp0

;)

[blobaugh]

Holy Crap!! I looked up that Paperdisk program. That's totally insane. Talk about some serious backup issues!

http://www.paperdisk.com/

[psi42]

Paperdisk...
1 megabyte compressed (originally 4MB of text) within an 8.5 by 11 inch space .


Wait a minute....... that's actually rather good.

Think about it.....CDs are nice, but they're thick...... Think how easy it would be to transport 10 pieces of paper--that's 40 MB of uncompressed text!

If we had a reliable way to scan it back in...