Longevity tests

lately i tested maybe 100 of my 1,5 - 3,5 years old CDRs. They were TDK, Verbatim, Basf, Sony, Samsung burned on 2 Yamahas and Teac. Maybe 40 percent has reading problems when tested on Toshiba DVD and Plextor burner, 20 percent is completely unreadable. I always test my burned CDs and all of them were ok before so this is the aging problem.
All the CD types have unreadable victims, but Sony (man: Mitsui) are all dead. Basf/Emtech (man: Ritec/unknown) problems are also very high.
So is this the longevity of CDs?
Then why do we even bother to store stuff on CDs.
I share this with people who could be as naive as i was and believe stuff on CDs is forever or for a very long time. :frowning:

Thanks. Could you say something more about your Verbatim and TDK media?
I have mostly Verbatim Azo from 4 years ago and some TDKs and they still perfectly readable.
Are “Azo” your Verbatim discs or “Datalife” made by Ritek? What is the percentage of errors in these discs?

PS: I have recent Kodaks silver+gold dying with less than a year.

I have the following old or unreadable discs:

  • Mitsui 2x, Fuji 2x: 5 years old, no errors (not even C2)
  • TDK Reflex 4x, 4 years old, no errors, not even C2
  • Auvistar / PostTech: 5 out of 6 were unreadable after 2 years
  • DST: unreadable after 1 year

It would be more meaningfull to have initial read-error tests on the discs to compare to the current ones. If they contained high levels of C1 or C2 errors initially, then the degradation would make sense. Discs that have low error rates tend to last a much longer time. But this is good information, and this is why I always recommend regular testing of any stored data, whether it’s on CDR, HD, or whatever.
Also, the conditions under which they have been stored would be usefull info. (ie: exposure to heat, moisture and UV).

I didn’t expose my discs to a non-recommended environment

a non-recommended environment

I use a FireKing media vault for the important stuff.

Maybe 40 percent has reading problems… 20 percent is completely unreadable. … I share this with people who could be as naive as i was and believe stuff on CDs is forever or for a very long time.
:<(
This is the feeling we’d all like to avoid, and that’s why I’m asking questions. (to avoid the feeling I had when discovering bad sound-quality on some of my old audio tapes)

Minix says,

PS: I have recent Kodaks silver+gold dying with less than a year.
From what I’ve read about Kodaks (at least the old Gold-Ultimas) they’re supposed to be very high-quality and reliable. ?? (bad batch? the new silver+gold aren’t as good as the old pure-gold? the reviews were wrong and the Kodak-hype was false? a bad media-and-burner relationship?)

rdgrimes says,

If they contained high levels of C1 or C2 errors initially, then the degradation would make sense. Discs that have low error rates tend to last a much longer time.
Why does this correlation occur? Do errors indicate that the burning process (to make lands & pits) didn’t go well, so the degradation (involving lands and pits, chemicals,…) is accelerated?

macMike

Why does this correlation occur? Do errors indicate that the burning process (to make lands & pits) didn’t go well, so the degradation (involving lands and pits, chemicals,…) is accelerated?

It’s all about having clean, regular edges on the pits and lands. As the disc degrades, any pre-existing irregularities, (the result of a crappy burn or crappy media), can get worse, making for poorer reflectivity and increasing errors. Drives can correct errors up to a point, but as the levels of C2 increase, the likelyhood of a failure increases.

Sounds more like your old writer was duff - in no way should so many discs from different and often respected manufacturers fail so badly after little over a year. It may have just written the pits with enough gusto to pass the old tests but they were badly written.

I have crap media from many years ago that has been stored in cool rooms in the open and they read just fine, All the Mitsui / Kodak / TY cdr’s I burn now I store in wallets in boxes in the dark.

Ice

Originally posted by macmike
From what I’ve read about Kodaks (at least the old Gold-Ultimas) they’re supposed to be very high-quality and reliable. ?? (bad batch? the new silver+gold aren’t as good as the old pure-gold? the reviews were wrong and the Kodak-hype was false? a bad media-and-burner relationship?)

Yes, they were very reliable, at least the gold ones.
The box I bought was when they dopped in price, a bit before they closed the bussiness. I guess that that drop in price was accompanied by a drop in quality.

I did even more test over the weekend and the results are much better this time. Seems i accidentally picked up the worst scenario CDs when doing first tests - i.e. when i started the topic.
I store CDs in original boxes, in darkness, no high temperatures, no humidity. Ordinary decent appartment enviroment.
Every branch has some dead CDs but they could be accidents and they could be no good burns.
Verbatims (all kinds) mostly just a couple of errors, many error free
TDK (just a few) just couple with errors
Sony (man: Sony/Mitsui) over 50 percent have bad reading problems, 30 unreadable
Basf 74 - all CDs undeadable!!
Basf 80 (newer ones) - many has reading problems, some completely wasted.
BEWARE of BASF!!! IT sux big time!!!

Who are your BASFs made by?

BASF or EMTECH
Manufacturer: Ritec and Unknown

do you have CMC? if so, how did they fare?

This can’t be right can it?

Surely they must last longer than this or what’s the point?

My old Amiga 500 collection of 3.5" DD disks are 12-15 years old and they all still work perfectly! No read errors! I know because I recently just transferred the whole collection to my PC. And the amount of abuse they’ve had is unreal! I’m writing the info over to CD thinking it’ll be safer before the disks finally do give up, but they might outlast the CD’s!

I expected CD technology to have a better lifespan than this - 25 years minimum!

Is this is how crap organic material can be for storage? We might as well go back to magnetic media!

No, no. It can’t be right. Ok I’ll probably be backing up all my info to dvdr in the next 2-3 years, but again will those disks have short lifespans?

I’m still not convinced cdrs are this crap…Mine are still fine from 2-3 years ago. I think you must have had a really crap writer or duff reader too. Or live near a nuclear power plant. :bigsmile: