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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
People have already posted they've had write-once CDR media last for years; I myself have media I created nearly a decade ago which doesn't show any (obvious) signs of degradation; admittedly I can't see in that cool color spectragraph they've produced (how did they make that, anyway?).
;) but my original 2^2 writer still works everywhere, including DVD players and portables (and, more importantly, on other peoples DVD players and portables). My own experience suggests that the burner is the more important factor then the media -- you can spot bad media right away because you start producing coasters at a higher rate.
The only problem I've observed over the last few years is problems between CDR hardware vendors. People bring me something they've burned on their new 52 speed writer and it only works on their reading hardware (or, more accurately, doesn't work in mine
If the price for faster burns or newer vendor equipment is a short(er) media shelf life, I'll stick with my original stuff and grow a beard instead.
"Please discuss this subject in our Media Forum."
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
Same experience here, some brands sometimes don't pass the year alive!
e s/recover cd.sh /. inserts, if any) :)
To try to recover the most of possible from cds (in data mode only), i have written a little shell script, basically it reads byte per byte (i know i should use blocks of 2048 but that was complicating the rest), if it fails on a reader, it asks you to put the cd in another one, etc
Some readers can read parts of damaged/old cds better than others etc... 2 cd readers required!
here is the link to the script:
http://lethalwp.dyndns.org/~lethalwp/fil
(suppress the space
i won't update the script any further.
+Funny, yes. But it might actually work when you embed the data into real pictures/movies. The technique of embedding is known as "steganography", and sometimes also as "digital watermark".
.WAV files. You could choose to use only the lower 4 bits (WAV 4x as large as hidden data) or the lower 8 bits (WAV 2x as large as data).
Scramdisk was an open source program to create encrypted containers (mount as driveletter in windows) in
Be the first to post a FLAC (lossles audio compressor) of the next hot EMINEM album, with some 200 MB of your personal encrypted backup hidden in it, and your backup will live forever!
Marc
Do a full backup once a year and a 20 month lifespan for the media doesn't matter...
I suspect that CD drives also have this capability, just that software doesn't bother to use that info. Actually, most software doesn't even appear to check for non-recoverable errors so I suppose it's being consistent.
And what kind of dye did the CDs use?
I remember when I was first investigating what brand of CD-Rs to buy. I read an article on the differences between the dyes used in CD-Rs.
Don't remember the exact details, but it was something along the lines of the chemical combination used to make CD-Rs with green dye are better for single speed reading (eg. Audio CDs) but didn't last as long. The chemicals used to make the silver/gold dye however were superior for data, and should last somewhere in the order of 20 years. I think blue dye was somewhere in between.
This similar article says gold dye CD-Rs have 100 year durability, and the cheaper green ones only have a 10 year life, but have been enhanced to give 20-50 years of service.
This might sound stupid. But what if I sealed the disc with grease, will this protect the media from reacting with atmospheric oxygen.
Later on if I want to remove the grease, which chemicals should I use so I don't damage the disc.
I still have the two CD-Rs that were included with my first CD recorder I bought about 10 years ago. They are hp brand and were recorded 2x speed. Both are working fine.
Not that there is anything of interest on them of course. At least if you are not interested in Winzip 2.0 or something of similar age. I just keep them out of curiousity how long they will be readable.
RedShirt
Microsft spel chekar vor sail, worgs grate !!!
I haven't had any high quality CDRs go bad on me yet. And by high quality I don't mean your bulk spindles, I mean Mitsui Gold, Tai Yuden, Kodak Gold (no longer produced), Verbatim DatLifePlus (stay away from ValueLifePlus), etc...
To be extra safe, I run two CD-R drives to write two copies of the data to two different brands of CDR medias at the same time. Then I also overlap the data for the next batch -- taking half the data from the previous CD, and adding new data to fill the new one. So that any given data is on no fewer than 4 good qulaity CDRs from two different brands/batches.
I also happen to have the a second drive in my computer (not RAID) dedicated to backups and quick recovery. Then there's also an external Firewire portable HDD that is another copy of the backup. I say you can never have too many backups.
This is how I backup my precious photos. For regular data, all of it fits on one CDR so at least once every month I write a full backup to a CDR. The CDR has got to last at one month right?
As for MP3s... that's what P2P is for.. distributed backups.
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
"Error distance" is nonsense. First of all, the turn on and off time for solid state lasers is miniscule. Second, this "error distance" is the same over the entire disc, and the on and off time should be roughly equal, so at worst you would have the pits "skewed" or delayed in relation to the actual input data. So what? The problem with the test was the variability of the the CD blanks. Cheap discs are cheap discs. Don't expect crap to last as long as name-brand media.
The other poster is correct. While we did not examine CD-RW, as they didn't really exist at the time, and also violated a rule for archiving for the group we were doing work for, which is that you can change them undetectably, I would imagine they suffer from the same problem as other mediums. Panasonic's phase-change designs were excellent, and substantially more stable than MO-RW, but in the end, they were VERY sensitive to UV, which is why they were in cases that had shutters that had interlocks. CD-RWs don't have this.
i *had* several panasonic phase change drives.
the media and technology is shit. period. it died off for good reason.
every single one of the discs died within a year with unrecoverable errors under even light occasional use.
even the crappiest CDR/RW technology I have seen is light years beyond that panasonic phase change crap.
ps i still have the drive and dead media sitting around, if anyone wants to buy it cheap...