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View Full Version : CD's lifespan woes.... any ideas?


madmac3d
12-23-2003, 12:14 PM
I'm currently going through the backup cd's at work to transfer them to dvd. We have found that around 5-10% of the cd's have become corrupt. Some are pretty new and most aren't scratched. I cannot understand that a cd burned 6 months ago, can have become completely unreadable without it being even used in that time!

Is there a truly reliable cd backup format ?

Are dvd's going to have the same unpredictable life-spans?

Is putting sticky labels onto the cd's likely to reduce their lifespan?

What recommendations do you have for a reliable backup regime in the office ? We have a tape backup, but it is automated and we only keep the 1 or 3 month tapes permenantly ( so some stuff might not make it onto the longterm backup )

It seems to me that having a few spare hard disks would be alot cheaper, more reliable and would save alot of time!

what do you think?

MattClary
12-23-2003, 01:08 PM
Have you tried reading the CDs on more than one machine?

dvornik
12-23-2003, 01:13 PM
Gotta say i've never had this problem. Could be a bad burner or low quality CDRs.

madmac3d
12-23-2003, 01:18 PM
oh yea... I've tried a few machines, and different drive types... cd / dvd...

I've also tried various cd repair software packages... but the results were less than successful, with most of the data garbled.... and they were incredibly slow....

I'm not sure if it is related to the media ... or the drive that was used to write them.....
basically they were fine imediately after being burned, but have corrupted themselves over a very short period of time. Infact most of the dud cd's were burned in the last year....
the reason I raised the issue of the cd labels, is that I started using labels mostly on those cd's that I've burned in the last year.... go figure!?

CourtJester
12-24-2003, 12:20 AM
I can't remember the site, perhaps it was the Inquirer, but I read somewhere that some CD-R's go bad quickly if stored in complete darkness, go figure.

I have found that my old data consistently occupies a small fraction of that occupied by the new; my previous system takes up 8 of 270 total GB, while the system before that occupies 500MB inside that 8GB. The footprint of old data has always been so small compared to current requirements, that I just "bring it along" and have it online rather than archived. For that reason, I do not use CD-R backups or other "archive" media, as all my data fits in online storage (plus offsite HD backup), all of which get replaced within an average of two to three years. The additional cost is offset by the convenience and speed of immediate access.

While that may not work for everyone, in particular those with several terabytes of data, 200GB of inexpensive hard drive storage would hold 300 CD's, and at less than a dollar per gigabyte, is still relatively inexpensive when redundant. And, what is a lot of data now will likely be just a drop in the bucket with tomorrow's storage capacities, so you'll be migrating it long before shelf life becomes an issue.

Emmortal1
12-24-2003, 01:30 AM
Odd, I have low quality CD's that I burned years ago and have kept in CD cases for many months at a time that work fine to this day. Very strange that they would say they go bad quickly in no light.

Emmortal

Medwyyn
12-24-2003, 01:31 AM
Not that it helps your current position, but there was an article posted recently by a DVD-CDR review site (I haven't been able to find the link yet) that contained a massive review of media shelf life for CD-R's. The results were surprising to say the least. The older the disc, the more data lost, even with brand name media, and even newer more recently burned media was showing, in some cases, rapid data loss. Most data burned almost a decade ago was mostly unreadable and unrecoverable. The general idea put forth by the article was that the CD-R media was not safe for long term data backup, especially vital data. I will keep looking for the report and post a link if I can find it.

parallax
12-24-2003, 10:15 AM
I've heard this story a few times the last couple of months.
This is a pretty serious problem.
Can you hold the media companies responsible for this??
They've always claimed that Optical data storage was a safe & secure way of backing up data.

Now i, and lots of other people have to rethink their data backup strategy (not that i HAVE lots of critical data, but enough to get anxious about it.)

On the other hand, i must say, CourtJesters method looks pretty sound to me.

GregHess
12-24-2003, 02:23 PM
One thing to also make sure, anytime your performing a true backup, is to run a VERIFY after the backup is complete.

Sometimes a small write error can slip by, and if your not testing each bit of data, on each cd, you could end up with a whole bunch of cd's with parts corrupted.

Which would be completely unrelated to cd shelf life.

My experience has been...as long as the cd's are kept sealed in a temp controlled environment, they'll easily last 10 years or so.

Remember to always make two copies of a backup. One for local use, and one for storage in a completely different location.

One of my friends had his house catch on fire and he lost not only his machines but years upon years of animation and models.

Now he keeps one set at his home, and mails the other set to his parents.

CgFX
12-24-2003, 03:17 PM
We brought this on ourselves with CD-R media that is either $.10 a piece or free with the rebate. :-)

Even the big brand names had to start labeling the cheap stuff to be able to stay in the game.

Ice Czar
12-24-2003, 03:45 PM
http://silverace.com/dottyspotty/issue12.html
http://www.mam-e.com/web/sys_coul.phtml
http://www.mitsuicdr.com/technology/dvd/index.html
http://www.cd-info.com/CDIC/Technology/CD-R/Media/Longevity.html
http://www.cdfreaks.com/article/113


http://www.cdrplanet.com/cdrplanet/cd-r-media--mitsui-cdr-media.html

PixelVampire
12-24-2003, 05:33 PM
hmm!!! SO where the hell do I buy these "Phthalocyanine " dye CDs in Europe??
I use this-
http://www.johnlewis.com/jl_assets/product/230160814.jpg

Can't tell what dye they use.

This one looks good-

http://www.kestonholdings.com.au/dbimages/tdk-cdr80%20gold%20100%20pack.jpg

Ice Czar
12-25-2003, 04:09 PM
Mitsui pretty much owns all the patents for Phthalocyanine Dye CD R \ DVD R

and MAM-E (http://www.mam-e.com/) is Mitsui Europe
as to specifically where....

dvornik
12-25-2003, 04:24 PM
Don't know guys.. For the last couple of years I've been using free KHypermedia and Optimum (whatever it was) and there were no problems whatsoever... And some $2 per 50 TDKs... It all works really well. KHypermedia is totally cool. I don't think they are crap cause they are free. You can research if you feel like it, they are really good quality....

parallax
12-26-2003, 11:58 AM
$2 for 50 CD's???

Your're lucky to get 10 quality CD's for $4/5 overhere.
Does that include anti-piracy taxes in the US?
Thats about 50 cents per CD in Holland.

GregHess
12-26-2003, 03:09 PM
You can pick up cheap DVD-R's here for a buck a disk. Even less in quanities of 100 or more.

Heck...best buy was giving away 200 packs of CDR's on black friday.

Of course this goes back to the whole...why complain about cheap cd's longevity thingy...

Wait why am I posting, its the farking holidays. I'm going to go play some video games with my sister.

See ya!

:wavey:

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