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CDs May be Less Immortal than We Thought
Zordak writes "The near-immortality of CDs, sometimes used as an excuse by record companies as an argument for their high cost, may not be as eternal as touted. An article at CNN describes the problem of CD Rot rearing its head to deny you access to your music and data. The article also describes related problems with CD-Rs, CD-RWs and DVDs."
cd rot has been known about for years, there's been other /. articles about it
While it might suck having to pay a nickel for music off of iTunes, at least I know that my data can be backed up in a manner of my own choosing.
I have been pwned because my
They don't last 10 seconds in the microwave.
Most CDs that have come out in the last 5 years have been nothing but rot...
We know CDs suck for longevity. This has been discussed on Slashdot more than JonKatz.
If Jesus wants me it knows where to find me.
I recently had to restore some data from CD-Rs I wrote a long time ago. One was labelled Sep 23rd 1993. Back when you got a 63minute CD-R for 25 ($40) a piece.
Everything restored perfectly. Now, I wonder whether todays discs at less than 1/100 of that price will even last remotely as long as those discs did.
Jolyon
Please read my Canon EOS tech blog at http://www.everyothershot.com
So, the RIAA has argued that we merely have a license for one copy of the music when we buy a CD. When the CD corrodes, does this mean we can turn in the rotted disc for a pristine one?
The theory of relativity doesn't work right in Arkansas.
CD's originally included Tellurium in their composition when they first came out, and a lot of people were concerned that it would oxidize. The effect would be that CD's produced in 1981 would become unreadable in ten years or so. I'm given to understand that aluminum is now used, but I wonder what ever became of those early CD's.
the music on the radio sounds worse every year?
It's nothing a little duct tape can't fix!
Keep the faith, share the code
Take my DVD collection, for example. Already the companies are battling to define the next standard. Who wants to bet that, if I take my DVDs down to the Target and ask for the same movie in the new format, I'm gonna get laughed into the ground? People's Betamax tapes are probably rotting too, you know?
A technology-independent, perpetual, safe storage service for the general public is just a business opportunity waiting to happen. So is the market to sell rights to a movie or song, independent of its format.
What media lasts LONGEST?
I mean, other than paper, or stone.
Ok, ammend. What DIGITAL media lasts longest? My first instinct is to say some type of tape, but tape drives seem to come in and go out of fashion fairly quickly. IDE drives might be another alternative...
So, for your money, what's the best media to store backups of your digital data? Anyone, anyone?
-- The unsig...
No, there's a limit on how many times you can encode the same playlist to CD. You can burn a song to CD as many times as you want.
that the billions of AOL cds in the world will eventually turn into something useful? like dust?
That is how many times you can burn a static playlist. Don't ask me why.
To make it inconvenient to mass-produce CD's from iTunes.
I write in my journal
All of the cd's that I have that have "rotted" or lost the metal layer that holds that data. Have been blank topped cd's ie no printing no nothing on top, just shiny metal. The cd's that I have that are labled or printed on don't seem to have any problem. I live in southern california and leave my cd's in my dark colored truck year round. Commercial Cd's and branded printed cd's seem fine as well as cd's with stickers on them.
---In a time of Chimpanzees I was a Monkey.
The CD or the copyright?
One of the things that's bugged me is that AFAIK, CSS and the like have NO provisions whatsoever for copyright expiration. I guess the ??AA can use this as a reason for never having any.
The living have better things to do than to continue hating the dead.
You may have not been doing this for malicious reasons, but you're statement is inaccurate! :)
According to Apple's site you can write songs an unlimited amount of times. You can only write a specific PLAYLISTS X amount of times. I think it's 5.
I have burned songs to CDs quite a few times and never had a problem. I've made at least 20 backups of my music collection, including purchased AACs.
iTunes has a very fair and very liberal usage policy IMO.
Zed's dead baby. Zed's dead.
Dan KOSTER.
is that perhaps with a soft "O", like "Coaster". I'd say so. He should change his middle name to "2000".
Some drink at the fountain of knowledge. Others just gargle.
Consumers have adopted a system by which multiple redundant backups are constantly made and remade.
It's called P2P.
"A great democracy must be progressive or it will soon cease to be a great democracy." --Theodore Roosevelt
But it's not iTunes' problem. Basically, all Apple cares about is making iTunes legit. By not facilitating mass production, they can claim they thier product doesn't contribute to piracy.
Once the CD is made, it's the same problem they've always had with CD copying. ie: not Apple's problem.
=Smidge=
The phenomenon of CD-Rot has been known for at least 15 years.
I believe it comes about when there are microscopic pin-holes in the aluminium layer within the CD. Over time, an effect akin to surface-tension in liquids causes these holes to grow - until they get sufficiently large (and numerous) to cause enough data dropout to overwhelm the error correction mechanisms of the player.
CD's that never had pin-holes don't develop them later - which explains how come some disks are magically immune to the problem where others die in only a few years.
I once heard that you can actually see these pin-holes once they've grown to a size that's not yet large enough to cause permenant errors. Hold the disk up to a bright light and see if you can see them. This may give you time to back up one that's "on the way out" before you lose it completely.
I believe the manufacturers developed an alternative material for the reflective layer about 10 years ago - but most pressing plants have not switched over to it. I wonder whether their reluctance to do so is rooted in a desire to have people re-buy the same CD's over and over.
www.sjbaker.org
Slashdot keeps its archives on CD-R. Each time they go to check for dupes before posting, they come up with nothing. :)
"Wow, you're like some kind of superhero able to ward off happiness and success at every turn."
-- Ryan Stiles
When they are using taxpayer money to do the tests, I don't see why the results (1) can't be disclosed and (2) shouldn't be disclosed (we paid for it!).
Sure, there are hacks and work arounds...but they aren't always readily available.
For instance...I bought Battlefield 1942 and couldn't make a backup. My little sister destroyed the 2nd disc. Now I can't reinstall it. I couldn't make a backup because the original disc contained bit errors. When I contacted EA, they told me to go screw myself.
Like most things, I too am an expert in this field (CD media)
RiTEK or Taiyo Yuden or Mitsui are "semi acceptable"
CDRs use frail ORAGANIC dye prone to steady erasure and destruction from heat, light, water, etc.
All media sucks for long term archival except perhaps STAMPED glass platter cds using gold sputterred reflection. They are called "Century Discs" and you have never seen one, though they are special fabbed. They are inorganic. No plastic to "droop" no aluminum to oxidize slowly into powder over the decades. (Aluminum oxidizes in 2 millionths of one second when exposed to air but creates a semi-safe blanket of aluminum oxide a couple atoms thick and remains mostly reflective.) All cdrs are slowly rotting, but if kept cold could last a while and be readable in a "flat bed static CD scanner" in 2020 and later.
Start of Side topic #1 ; inorganic home recordable +100 year archival media:
I own "mostly inorganic" glass platter PDO media for archiving with a four and a half thousand dollar device I bought once. It's a Maxtor (Maxoptix) Tahiti-II and each blank cost over 100 dollars. But the data will last centuries under ANY HEAT and ANY atmosphere and ANY Radiation and ANY magnetism because it uses PLASMA STATE recording. A rare earth element is heated past liquid, past gas state, into PLASMA STATE by a ridiculously espensive high powered laser, and while in this state, a strong magnetic field orientates the crystals of the cooling rare earth metal into north-or south orientation. A simple low power read-only laser can use a polarizing filter to readily discern this data. It can do so centuries from now. The Library of Congress uses these 4 thousand dollar recorders, and the US military... and also myself for pleasure. Yup I stored porn on these Tahiti-II glass platter inorganic discs! Too bad the timing-tracking marks embedded in these crystal media 125 dollar platters was imprinted using a plastic marking substance instead of the official "acid etching using H2SO3F+" Magic acid.
Only magic acid can eat a beaker or mark the inside timing marks of these special multi-century media... and Phillips Dupont CHEATED ME and fucking used PLASTIC which will rot away slowly over the next 75 years depriving our future generations of my porn collection. You can buy magic acid in special containers, or manufacture your own by mixing antimony pentafluoride (SbF55) and fluorosulphonic acid (HSO3F). It has an unbelievable pka of 20 and is powerful enough to protonate saturated alkanes forming carbonium ions... and etch glass without spending a lot of effort trying to use hyperboloid 5Kw lasers on clear glass.
UI am definitely going off on a tangent and I was still talking about CD reflectivity, so I will continue...
End of Side topic #1 ; inorganic home recordable +100 year archival media:
I have visited pressing plants, sputtering plants, and even polycarb manufacturers for DVD and CDR, and taken a few 1,200 dollar a day seminars on laser head movement and design.
Refectivity in a CD or CD-ROM is irrelevant. The laser usually uses a "Quarter wave" plate and the frequency of the laser is specially selected and this rotated light has a 90 degree polarity difference (differential phase) that makes reading possible at high speeds. This is less relevant in CDR but very important in stamped media. I discuss this at length for you below a second discussion in my Side topic #2 on : CD Reflectivity Layers (not needing any metal or even being transparently covered)
Amusing Side NOTE : I am not just Mr Medical boy, Mr microbiology Man, Mr Lawyer, Mr Musician, Mr Trivia Buff, Etc... i am also Mr Computer expert and CD device consultant, and paid a couple times in my life to consult on CDR mechanism design.
The best CDRs use a special dye invented by Mitsui Toatsu Corporation (MTC), but no longer true after 2000 unless you have old stockpil
Kodak Gold CDs - which are the discs which quote 100 year life span, use an inert gold refective substrate, and the dye technology used for the write layer is quite similar to the dyes used for their film stocks. Typically these disc will have a slower maximum burn speed as they need slightly more heat/energy to set to dye state to a 1 or 0.
Sara
Designer, Gamer, Macgrrl in an XP World