In a message dated 12/20/1999 "earthlink" <catsmaster@xxxxxxxxxxxxx>
writes:
<< Well, ok I do concede that we do not know exactly how long CDRs will
last,
but I still have never heard of a 5" disc delaminating under normal
conditions, Have you or Ken ever seen a delaminated one?
I have repaired thousands of CDs including CD-ROM and playstation discs
in
the last couple of years, some of them dating back to when CDs first
came
out(about 16 years ago), and yes I have seen many with pits in the
label,
but no signs of delamination. Those with pits in the label have almost
always been on discs that used the clear lacquer coat only vs. those
with a
solid silkscreen. The pits don't just happen though, it also has do with
how
they are handled. >>
My "day job" background is that of a consumer electronic technician so
while I don't repair CDs themselves, I have a vast amount of factory
training and experience in the repair of Laser Disc and CD players
(Pioneer training begining in 1981 and Sony training begining in 1983,
ex-employee of Sony Corp. and Philips CEC, etc.).
While I have not seen delaminated disc myself, but I have heard of them
in areas of extreme climates (Santa Cruz, CA. is not known for that).
The pinholes that Ken spoke of were a very harsh reality in the 80s.
Polydor was the culprit and the defects were indeed right out of the box
prior to any handling. I personnaly had to exchange many and I had to
advise customers to exchange countless ones. That manufacturing problem
is long since fixed and is not an issue in this day and age. As I'm sure
you are aware though, scratches on the label side destroy data (or the
reflectivity that allows the pick-up to see the data). As you point out,
with proper handling this should not become an issue. Other
manufacturing defects in the earlier years of this technology include
off-center spindle holes and warpage (the later being more of an issue
with 12" laser discs).
This all said, I too have all of the first CDs I ever bought back around
'83 or so and they are all still just fine. I am curious how you
"repair" CDs since my kids do tend to be kinda hard on their
Playstation, CD ROM, and now Dreamcast (sigh...no wonder I can't afford
that 350 f2.8 I lust after!). My understanding is that they can be
polished out...what is your recommendation for the type of polish and
method to use? TIA for your advice. (So far, I just clean 'em and it
helps a lot after the kid's grubby little paws get on them.)
<< I would still archive on CDRs for now, not magnetic media, when
something
better comes along in ten years or so, it should be easy enough to
transfer.
I believe your right though about CDR/Ws, I would not feel safe with
those
keeping data flawlessly for ten years. >>
Yup...seems like prudent advice. As far as archiving goes, I'm not too
concerned with the files that I scan myself on a desktop scanner but
those ~100 meg files you pay a service bureau dearly to create on a drum
scanner best be archived carefully since they can be a sizeable
investment.
Mike Veglia
Motor Sport Visions Photography
www.motorsportvisions.com
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