I store all my vital information on a Cardassian one time Opto-lithic Data Rod imported straight from the Top Secret Obsidian Order supply Depot on Cardassia IV.
It costs me several liters of Bio-mimemtic gel per Exo-byte, but it is worth it.
Posted on 08/26/2014 9:52:12 AM PDT by a fool in paradise
Many institutions have their archives stored on CDs — but the discs aren't as stable as once thought. There is no average life span for a CD, says preservationist Michele Youket, "because there is no average disc."
---
Back in the 1990s, historical societies, museums and symphonies across the country began transferring all kinds of information onto what was thought to be a very durable medium: the compact disc.
Now, preservationists are worried that a lot of key information stored on CDs — from sound recordings to public records — is going to disappear. Some of those little silver discs are degrading, and researchers at the Library of Congress are trying to figure out why.
In a basement lab at the library, Fenella France opens up the door to what looks like a large wine cooler. Instead, it's filled with CDs. France, head of the Preservation, Research and Testing Division here, says the box is a place where, using temperature controls, a CD's aging process can be sped up.
"By increasing the relative humidity and temperature, you're increasing the rate of chemical reaction occurring," she says. "So we're trying to induce what might potentially happen down the road. That gives us a feel for how long things are going to [take to] age."
France says part of what they are trying to do here is determine the minimal conditions needed for libraries and archives everywhere to preserve CDs.
"Smaller institutions don't have the resources to control environments tightly," she says. "One of the things we try to do is sort of look at how wide can that range be, as long as it doesn't fluctuate too much. And [if] it's stable, then that's usually the best thing."
Unfortunately, this testing has also found that not all CDs are the same. Michele Youket, a Library of Congress preservation specialist, plays a CD of classical piano rhapsodies by Erno Dohnanyi. It crackles, and eventually the sound just cuts out.
This is a variant of what's called "CD rot," Youket explains. In this case. it's what's called "bronzing." The outer coating of the CD erodes, leaving a silver layer exposed. And when you leave silver exposed, it tarnishes.
"So it's actually changing the composition, and that's why you hear the scratching there," Youket says.
And here's the thing about CDs: Youket says part of what makes it hard to preserve CDs is that they are not uniform. There were a lot of different standards of manufacturing, depending on the year and the factory.
"This phenomenon of bronzing was particular to only discs that were manufactured at one particular plant in Blackburn, Lancashire, in England," and only between 1988 and 1993, Youket explains.
"Everyone always wants to know the answer to the same question, 'How long do CDs last? What's the average age?' " Youket says. But "there is no average, because there is no average disc."
The Library of Congress has around 400,000 CDs in its collections, ranging from congressional records to popular music, and the library regularly gets donations of CDs.
Real estate records and titles were also moved from microfilm to CD beginning in the 1990s all around the country, says Jim Harper, president of the Property Records Industry Association.
"They just made the move because they thought anything that was digital, anything that was electronic, was going to be far superior to anything from the past," Harper says. "And it turns out that that was indeed wrong."
With budgets tight for local governments, Harper says most are not going to be able to move to another form of storage in the near future.
PRIA has been taking Youket out to speak to county officials, to at least make certain they understand the problem they're facing.
"We've been working very hard to ... say, 'Listen, if you're going to use these things, you better be careful what you buy, because it's not all created equally,' " Harper says.
Increasingly, CDs aren't being created at all. The record shops that sold them are going out of business, and new computers don't come with CD drives any more. Even so, many of us still have dozens or hundreds of CDs. All Tech Considered Museums Give Video Games Bonus Life, But The Next Level Awaits
Researcher France says many of them can actually last for centuries if they're taken care of. "The fastest way to destroy those collections is to leave them in their car over summer," she says — "which a lot of people do."
Sadly, your favorite CDs — the ones you've played a lot — are often the ones that are most likely to be damaged.
These days, the Library of Congress is starting to archive material on servers, which France acknowledges could pose an entirely different set of still-unknown problems in the future.
The better mousetrap usually isn’t.
At least the change to CD wasn’t mandated by the government as cooling systems, televisions, toilets, and other items commonly used in the home were.
Don’t worry... Lois Learner’s email was archive on Compact Disk too.
rock carvings last almost forever.
That’s great, as long as the LP doesn’t have any scratches.
Longevity starts with the quality of the CD itself and the quality of the burn.
Almost all CDS sold retail are trash made in basements in Taiwan. Brand means nothing as the actual CD vendor changes from batch to batch depending which basement is cheapest that day.
The only really good CDs are made by Taiyo Yuden, but be sure the ones you buy are not counterfit TYs.
I just assumed all of my CD’s were top notch quality. After all, they are delivered in ‘jewel cases’ which we all know to be durable and made with a very high level of craftsmanship.
Strange - after all the ‘high tech’ it may be best, after all, simply to own books.
And how many people are there who don’t leave their CDs in the car all year ‘round?
Funny, the Rosetta stone’s been around a while. Not so much the complete collection of the Dead Sea Scrolls, though.
Many institutions have their archives stored on CDs — but the discs aren't as stable as once thought. There is no average life span for a CD, says preservationist Michele Youket, "because there is no average disc."
Back many years ago, when audio CDs were new and data CDs were just coming in, the buzz was all "indefinite", as though they were eternal.
I talked with Bill Henderson, then the University of Illinois' preservation librarian on that multiple times. He did not buy it.
Deterioration of the reflective layer isn’t the only problem.
The base layer of a CD is made of polycarbonate plastic, something I had assumed would last practically forever — not so. I bought a number of Telarc music CD’s in the late 1980’s. Several of them have completely cracked while sitting in their jewel cases inside a dark record cabinet. My house is air-conditioned year-round, so there are never humidity or temperature extremes.
Meanwhile my vinyl LP’s and shellack 78’s remain good as new.
How often do you listen to the Rosetta Stone? And it's not even in Hi Fi.
If you live aboard a boat, forget CDs - the dampness is very destructive.
That and the fact that I had a CD changer I nicknamed "Old Scratchy" are the reasons I got in the habit of copying every CD I bought and only playing the copies in the car.
The only really good CDs are made by Taiyo Yuden, but be sure the ones you buy are not counterfit TYs.
Those are the main blanks I buy for writable media.
Pressed CD = almost forever...
Burned Cds..... Depends onthe dye used...
I store all my vital information on a Cardassian one time Opto-lithic Data Rod imported straight from the Top Secret Obsidian Order supply Depot on Cardassia IV.
It costs me several liters of Bio-mimemtic gel per Exo-byte, but it is worth it.
Compact discs are a godsend to people who live with cats. No more pop ..... pop ..... pop ..... pop as another cat hair gets stitched into soft vinyl grooves.
Flash has a duration of about seven years. In no way should flash be used for archival. You will start to lose some cells (bits, really) in as little as five years.
Unfortunately, Taiyo Yuden is old news. They were bought out and have been producing so-so discs since then. I have been having very good luck with Falcon media, but I am not sure I would hold them up as a standard.
You are quite correct about brands and disc sourcing. If you buy discs from a media vendor, they are generally going to know what is going on in the industry and what discs they have which are quality - both in the disc manufacturing and the dye being used. If you buy discs at Walmart, I would say they are fine for a year or so and fine to transport files but not good for archival at all.
The Revenge of Vinyl!
Vinyl is Final!
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.