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Say Goodbye To Your CD-Rs In Two Years?
Little Hamster writes "According to an article on cdfreaks.com, a test done by the Dutch PC-Active magazine showed that among 30 different CD-R brands tested, a lot of them were already unreadable after twenty months. This is shocking, and makes me wonder how should I backup my data, photo and music collection."
You can buy special transparant stickers for that. They cover almost the whole CD. You need a tool to stick them on properly. See here.
-- Cheers!
Although they are of a similar tech, what about DVD recordable disks? I've got plenty of those now...
This would be as good a place as any to mention TDK's Armor Plated DVD Media, which are supposed to keep on working even after having been scoured with steel wool pads. Also, Verbatim makes a line of scratch-resistant CD-R media.
There are two kinds of people: 1) those who start arrays with one and 1) those who start them with zero.
CDRs are much more reliable than hard drives. Each hard drive has a high probability of failing in the first two years. That's likely why the warranty on new drives was recently reduced to 12 months. CDRs, if they are high quality and are properly stored, can last many years.
This Site has been kicked around slashdot lots of times and depicts a man, a dremel, a CD and 30,000 RPM's of angular velocity.
[Fuck Beta]
o0t!
I used to work in a CD factory (from 1986 to 1994), and this is plain not true. A pressed CD consists of:
disc label
protective coating (laquer)
Aluminum layer (sputtered on)
data layer (pressed into the next layer when injection molded)
polycarbonate injection molded disc
To vary from this is a violation of the Phillips spec, and you are not allowed to put the Compact Disc logo on the resulting product.
What you probably noticed was the laquer layer was thick when we started making discs, but over the years laquer has improved to the point that only a very thin layer is needed.
If you leave out the laquer entirely, the aluminum oxidates rapidly, rendering the disc useless.
Long story short the rule of thumb was like this: Green CDs have a life of ~5 hours. Yellow CDs ~20 hours. The DARK DARK Blue cd's (not light blue, the only brand I know of like this is Verbatim) *600* hours.
The price increases correspondingly as well. I found the best solution was to use blue's for backups and critical things, and regular commodity cd-r's stuff for day to day things.
Religion is a gateway psychosis. -- Dave Foley
I've always wondered if this [burning at 1x speed results in better CD's] is actually true or not.. I have yet to see any actual evidence to back up this claim...
Well, head on over to cdfreaks.com website and take a look at the results of some tests. For the lazy among us, burning at 4x resulted in more C1 errors in every test posted (on page 1, page 2 timed out) than burning at a higher speed (usually 40x, but one test was at 52x). A comment on page 2 indicated on person did 4 tests, and half said burn at high speeds and half said burn at lower speeds. Overall, the small sample of results indicated that burning at low speed usually makes things worse, not better. Surprising huh?
I remember way back when, around when CD-R's first came out, they had a type of organic dye that appeared gold whos purpose was for data archival. I have a few of these and quite a few of the old blue Verbatims and some no-name green media. All of these are still quite readable, and they were burned in 1996. Perhaps one of the reseachers in the article left their CD-R's on the dashboard of their car and didn't own up to it.
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The other thing to consider is that DVD-R/+R technology is dropping though the floor. I bought a Pioneer A05 for $320 in January and today the A06 is going for $229., and remember I bought this thing from the same place I linked to. I don't know how DVD-R is for archival, but my point is that at the rate the technology is falling in price, CD-R may not be around much longer anyway.
In any case, I found a rather excellent guide on the different tyes of CD-R media. It goes over all the dyes, their manufacturers, theoretical lifespans of the dyes, etc. I recommend a visit...
http://www.cdmediaworld.com/hardware/cdrom/cd_dye
-R
Does it matter? Yes. Is slower always better? No.
Rather than re-hash this, please see:
In the CD-Recordable FAQ.Quick summary: higher speeds require a different "write strategy" than slower speeds. Different media formulations are optimized for a particular write strategy, so writing slower than the optimal speed can actually produce inferior results.
The choice of media and recording hardware has to be taken into consideration. In any event, this has relatively little to do with disc deterioration. A disc that's better to begin with won't show the effects of physical deterioration as soon, but if the top lacquer coat isn't as close to air-tight as materials allow, it doesn't matter how you write the disc.
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MAM-E Gold Ultra, about Eur. 1.15 each.
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Mitsui Gold Ultra, about $1.60 each.
Kodak used to be in this market, but seems to have exited it.The key here seems to be dye type. Phthalocyanine has slower writing speeds but longer storage life; Cyanine has higher writing speeds but much shorter storage life. The "archival grade" CDs also have gold reflecting layers and a tougher substrate.
There are also "Medical grade" CD-R blanks, but they're essentially the same as the archival ones.
There are programs which will read the ATIP information from a blank, telling you what the manufacturer, max writing speed, and dye type is.
MAM-E Gold Ultra CD-Rs are guaranteed by the manufacturer to last for at least 200 years.
From a little googling, I now see that they signed a Memorandum of Understanding with the Rainforest Action Network promising to change their ecologically unfriendly corporate practices. Here is the link:
http://www.ranamuck.org/news7.01mitsi.htm
Provided the humungous Mitsubishi zaibatsu is living up to their promises, I have no problems now recommending Mitsubishi Chemical CD-Rs. Everything I said about TY goes double for their disks.
The reasons why TY and Mitsubishi CD-R blanks are so good and so compatible are the fact they use a much darker dye than the Taiwanese manufacturers do. Yamaha suggested the use of Mitsubishi Chemical CD-Rs with their "Disc T@2"-equipped burners because the graphics would show up better. They are a better choice for maximum compatibility for the same reason they are a better choice for "Disc T@2". The more visible the dye layer is to the naked eye, the more visible the dye layer is to a CD-ROM or CD player's laser.
I wish I could back my assertions up with a whole list of studies, but I am basically speaking from several years of my own experience with CD-R blanks. I don't see as many CD-Rs made by TY going bad as no-name Taiwanese crap does.
Knowledge is power. Knowledge shared is power multiplied.
The two main CD-R companies are Ricoh, in Taiwan, and Taiyo Yuden in Japan. Now which company do you suppose makes the better discs? Check the "made in, hecho... etc." label before you buy discs. "Made in Japan" discs are head and shoulders above Ricoh discs. Not only do they have higher standards in Japan, they also use higher-quality dye. After that the main thing to look for is a nice, non peeling top. I recommend Fuji, Mitsui, HP, and Kodak discs if you are looking for a CD-R that will keep your data safe. I've burned thousands of CD-Rs over the last 5+ years, and not a single one of my archive discs have ever "gone bad", or flaked out on me. Those archive discs are mostly TDKs from back when they were made by TY, and Fujis.
Anti-social? My code is just platform-specific.