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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."
The CD is an inferior storage technology that has propagated due to 3 reasons IMO.
1. For the average person, a file is in some way less real if it is on a hard drive, and more real if it is on a CD, where it is a physical object they can touch.
2. Familiarity with CD's due to long term use on music CDs.
3. Vastly superior marketing to hard drives.
Removable hard drive bays should be standard on all PC's. Once you are used to these, the Hard Drive is just a Cartidge to plug into the PC. Data is easily backed up, and a Hard Drive in closet is safe.
Hard drives are faster, take up less space, and are very cost competative with CD's. I am unclear why CD's are popular with the tech savvy crowd. It's an inferior storage technology.
HenryJamesFeltus.com
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!
You can do the experiment, but you will need a cheap-o-media try burning at 1x and then at the maximum your CDR drive can handle, and try it on a variety of CD-ROM drives, the odds that the 1x copy will be readable on more drives.
I still have a SONY CDR burned at 1x in 1997 ! and still works just fine. (but useless old software anyway)
I agree.. Slower recording speeds will usually improve the contrast ratio of the resulting recording.
One can confirm this by making several cd-r's writing at different speeds using the same type of media, and then visually comparing the cd-r's data surfaces, (For recorded areas, Darker is better).
A fair number of CD recording programs DO NOT have a VERIFY cd-r contents option after a burning, and is a major pain in the ass. This problem got me good when I used some 12x Office Depot media for saving some TV show mpegs. Bad move, :-(
I found out months later, that 50% of initial recordings had one or more non recoverable bad spots.
Nero is the only mastering program I know of, which will verify cd-r contents after burning :-),
:-( .
But it doesn't do it for all recording formats
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!
Do a full backup once a year and a 20 month lifespan for the media doesn't matter...
Ahhh, any veteran of the Commodore 1541 floppy drive can tell you what this is: alignment errors. You see, the head is moved using these little step-motors. With use, the motors drift out of alignment, meaning the head moves somewhat less (or more) per "kick" than it's supposed to. As long as it's the same motor, that error occurs on every operation, so there's no net effect. (That is, sure, the data's in the wrong place. But during read-out, the head will seek to the (same) wrong place. So no error.) But move that disk to another machine, whose step-motor has a different alignment, and BAM! read errors.
Fans of the C1541 will remember what happens when that drive found an alignment error: CLACKETY-CLACKETY-CLACKETY-CLACKETY-CLACKETY-CLAC
The Mongrel Dogs Who Teach
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.
Do you remember science class where they told you a measurement wasn't correct unless it included a +/- error estimate?
Every CD burner (like every real-world device) has a certain amount of error. The device decides to turn the laser on or off, and there is a delay before the laser turns on or off. This small delay varies with heat and other factors within the device and varies with the component tolerances from device to device.
This error rate is over time, not distance. So, if the CD is rotating slower, it doesn't move as far during the error period. This results in a burn which is closer to perfect, that is it has less error distance than a higher speed burn.
Then there is the completeness of the burn; with a brand new good quality drive it shouldn't matter, but how many of you have a brand new plextor?
And of course there's also the CD media. If you bought the 10 cent bulk discs and expected them to last, shame on you. I record at slow speed to the old dark-blue verbatims whenever I can, and after 7 years I havn't lost data yet.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
Why does every porn joke get instantly rated "5, Funny"?
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
Why does every porn joke get instantly rated "5, Funny"?
I'd explain, but it takes too long given that I'm typing one-handed.
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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.
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Sorry paper rots over time, and there is always danger of a fire. The ultimate backup is cuneiform on clay tablets. They remain readable after thousands of years.
Quemadmodum gladius neminem occidit, occidentis telum est
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
The test I do now (which I learned the hard way from early burning experiences) is to hold the cd-r up to the light. If you can see through it, chances are it won't last. The cheapo bulk disks that have nothing but a silver top are very likely to be the first to flake on you.
Also, keep your burned discs out of direct sunlight and excessive heat, both which will cause the top foil layer to come off. Even quality media will give out on you after exposure to the elements.
If you can't beat them, arrange to have them beaten. -George Carlin
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.
It is absolutely true. It becomes increasingly difficult to create well-formed pits at higher rotation speeds due to the more difficult timing tolerances. Also, it is easier to get predictable burn results at a lower laser power setting.
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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.
Close, but actually it is inducing a color change in an organic dye. This dye is either green (unburned) or clear (burned), and is sandwiched between a reflective and a non-reflective layer.
-- You are in a maze of little, twisty passages, all different... --
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.