Scientific data on optical medium longevity.
jardinero
For all of us concerned with the longevity of optical disks and the
effects of dust, fingerprints, labels, etc. on them, download an
excellent pdf file written on the subject.
Scientists working on the Digital Preservation Program at the National
Institute of Standards and Technology (NIST) have released an
excellent 50 page guide ( http://tinyurl.com/2x43f ) on care and
handling of CDs and DVDs for long term storage.
It's 50 pages long, but your will find more information in it than
anything you have thought of concerning optical medium.
Maybe this file will put an end to so many myths concerning aging DVD,
CD, etc...
Thomas A. Horsley
>Institute of Standards and Technology (NIST) have released an
>excellent 50 page guide ( http://tinyurl.com/2x43f ) on care and
>handling of CDs and DVDs for long term storage.
Looks like an excellent paper, but they use the same jargon about "markers
that contain solvent" everyone else seems to use. Can't someone just tell
us in plain english if Sharpie markers have any of this nasty "solvent"
stuff the CD makers warn about? :-).
--
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Rick Pali
> Can't someone just tell us in plain english if Sharpie
> markers have any of this nasty "solvent"
> stuff the CD makers warn about? :-).
Just smelling the business end of a Sharpie tells me they're not
water-based!
Rick.
-+---
rp...@alienshore.com
http://www.alienshore.com/seeking/
Tim Kroesen
failed discs by now to prove the issue ...<g>
Tim K
"Rick Pali" <rp...@alienshore.com> wrote in message
news:fozUb.146502$9Ce1....@news04.bloor.is.net.cable.rogers.com...
Phil
dissolve the portions of the base layer before it evaporates I don't
think you can fret too much on cd's already marked. If the data is
still good it most likely won't suffer further deterioration from the
marks.
I've never known alcohol to be a paint or hard coating removing agent.
However, I suspect dipping the cd in carburator cleaner, naptha, MEK, or
acetone may be deleterious to the coatings.
I believe some of those would dissolve the plastic disk as well.
Rick Pali <rp...@alienshore.com> posted in
news:fozUb.146502$9Ce1....@news04.bloor.is.net.cable.rogers.com
--
Phil
mike
>
> Thanks
>
>
Just click it to open the pdf reader. Stop the reader then save page as...
I don't understand why people have to post links like this, but it's
done a lot. Maybe it lets them put more popups on your screen.
mike
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Bunch of stuff For Sale and Wanted at the link below.
Toshiba & Compaq LiIon Batteries, Test Equipment
Honda CB-125S $800 in PDX
TEK Sampling Sweep Plugin and RM564
Tek 2465 $800, ham radio, 30pS pulser
Tektronix Concept Books, spot welding head...
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Noik
Horsley) wrote:
>Looks like an excellent paper, but they use the same jargon about "markers
>that contain solvent" everyone else seems to use. Can't someone just tell
>us in plain english if Sharpie markers have any of this nasty "solvent"
>stuff the CD makers warn about? :-).
Sharpies are alcohol based, not the same stuff as the "solvent" based
markers they talk about. They don't really hesitate to recommend
cleaning disks with alcohol, so they apparently think alcohol is safe.
But who knows what evil might lurk in the ink/dye/whatever that
Sharpies use? Who knows what evil might lurk in the ink/dye/whatever
that water based markers use? I figure there's no reason to think that
Sharpies are less safe than any other marker.
N
Brendan R. Wehrung
> Alcohol as well as many other solvents, evaporate. If it doesn't
> dissolve the portions of the base layer before it evaporates I don't
> think you can fret too much on cd's already marked. If the data is
> still good it most likely won't suffer further deterioration from the
> marks.
>
> I've never known alcohol to be a paint or hard coating removing agent.
>
> However, I suspect dipping the cd in carburator cleaner, naptha, MEK, or
> acetone may be deleterious to the coatings.
>
> I believe some of those would dissolve the plastic disk as well.
>
Hold onto that thought. It won't be that long before the "how do I
absolutely destroy access to data on a disc?" question comes around again.
Brendan
--
Mike Richter
>>Scientists working on the Digital Preservation Program at the National
>>Institute of Standards and Technology (NIST) have released an
>>excellent 50 page guide ( http://tinyurl.com/2x43f ) on care and
>>handling of CDs and DVDs for long term storage.
>
>
> Looks like an excellent paper, but they use the same jargon about "markers
> that contain solvent" everyone else seems to use. Can't someone just tell
> us in plain english if Sharpie markers have any of this nasty "solvent"
> stuff the CD makers warn about? :-).
Sanford themselves say that their markers with water-based inks are
preferred for plastic, including CDs.
Mike Richter
1. Cleaning the business side of a disc means wiping polycarbonate. Not
an easy material to degrade.
2. Cleaning or otherwise putting a solvent on the top layer means
exposing an acrylic lacquer to the material - quite a different matter.
3. If anyone recommends cleaning the top of an unprinted disc with
alcohol, I've not seen it.
4. There are known cases where the ink itself leached through the
acrylic lacquer to destroy even pressed discs. RCA had a large set that
had to be repleased when they tried a new ink - one which matched the
red of their red-seal 78s.
5. Sanford says that the Sharpie is less safe than their own pens with
water-based inks.
But, then again, what would the manufacturer know about his product?
[NOTE: There are discs with a durable overcoating which can survive
alcohols and for which the Sharpie is fine. I use a Sharpie on discs
prepared for ink-jet printing, for example, but for those without such
an overcoating, I use the TDK CD Writer or another pen with water-based
ink.]
Mike Richter
> Please can some one post a Active URL on this..
TinyURL's have finite life. The link has been posted at my WWW site for
some months:
Standards Published on Permanence of Electronic Materials
http://www.cd-info.com/CDIC/Industry/news/ansi.html
Noik
wrote:
>5. Sanford says that the Sharpie is less safe than their own pens with
>water-based inks.
Pointer?
>But, then again, what would the manufacturer know about his product?
Manufacturers know a lot about marketing new products. Are you saying
that alcohol might be dangerous to lacquer (huh?), or that the
ink/dye/whatever in the alcohol based marker might be more dangerous
than the ink/dye/whatever in the water based marker?
>[NOTE: There are discs with a durable overcoating which can survive
>alcohols and for which the Sharpie is fine.
How do you know that the overcoating is less susceptible? How do you
know that the overcoating won't react with a Sharpie and ultimately
raise hell by creating stuff that affects the lacquer more than the
Sharpie by itself would have affected the lacquer?
> I use a Sharpie on discs
>prepared for ink-jet printing, for example, but for those without such
>an overcoating, I use the TDK CD Writer or another pen with water-based
>ink.
How do you know that that ink won't be worse than the ink in a
Sharpie?
N
smh
Mike Richter, were you born with
"Scam Artist" emblazoned on your face?
--------------------------------------
(Mike Richter, any Material Connection w/ Roxio?)
http://groups.google.com/groups?selm=3F2D8973...@mindspring.com
(Messages 10, 12 -- 34, 54 -- 69)
( No pipsqueaks have been able to prove ANY of the above is a libel )
( -- despite Mikey's supposed to have proof of misquotes! )
London Midland & Scotland wrote:
> Please can some one post a Active URL on this..
Subject: [7-5] How long do CD-Rs and CD-RWs last?
http://www.cdrfaq.org/faq07.html#S7-5
http://www.itl.nist.gov/div895/carefordisc/disc_care/
http://www.cd-info.com/CDIC/Technology/CD-R/Media/Longevity.html
smh
Mike Richter, were you born with
"Scam Artist" emblazoned on your face?
--------------------------------------
(Mike Richter, any Material Connection w/ Roxio?)
http://groups.google.com/groups?selm=3F2D8973...@mindspring.com
(Messages 10, 12 -- 34, 54 -- 69)
( No pipsqueaks have been able to prove ANY of the above is a libel )
( -- despite Mikey's supposed to have proof of misquotes! )
Mike Richter (Friggin' Scum) wrote:
>
> London Midland & Scotland wrote:
>
> > Please can some one post a Active URL on this..
>
> TinyURL's have finite life. The link has been posted
Are www.cd-info.com and www.itl.nist.gov the same, Mikey?
>
> at my WWW site for some months:
>
> Standards Published on Permanence of Electronic Materials
> http://www.cd-info.com/CDIC/Industry/news/ansi.html
Only for some months, not years, Mikey?
--------------------------------------
From old CD-R FAQ:
Subject: [7-5] How long do CD-Rs last?
(1998/10/16)
See also
http://www.cd-info.com/CDIC/Technology/CD-R/Media/Longevity.html,
especially
http://www.cd-info.com/CDIC/Industry/news/media-chronology.html about
some inaccurate reporting in the news media.
--------------------------------------
Eric McG
--
Hope this helps..Reply in newsgroup only.
Eric McGillicudy
"London Midland & Scotland" <l...@rail.co.uk> wrote in message
news:4hp620h0hac40er9g...@4ax.com...
> On Thu, 05 Feb 2004 20:59:48 -0800, Mike Richter <mric...@cpl.net> wrote:
>
> >London Midland & Scotland wrote:
> >
> >> Please can some one post a Active URL on this..
> >
> >TinyURL's have finite life. The link has been posted at my WWW site for
> >some months:
> >
> >Standards Published on Permanence of Electronic Materials
> >http://www.cd-info.com/CDIC/Industry/news/ansi.html
> >
> >Mike
>
>
> But from what I can see this is not a Free Dnload and no direct link to
the
> article at all.
>
>
Phred
London Midland & Scotland <l...@rail.co.uk> wrote:
[snip]
>
>This what I get with that URL
>
>Warning: mysql_pconnect(): Can't connect to local MySQL server through socket
>'/var/lib/mysql/mysql.sock' (11) in /home/sites/site15/web/db_connect.php on
>line 3
>
>Fatal error: Call to undefined function: mysqlerror() in
>/home/sites/site15/web/db_connect.php on line 3
Have a squiz at this link, might be the same/similar:
http://www.itl.nist.gov/div895/carefordisc/disc_care/toc.html
Note: The "printable version" on the various pages only refers to the
current part, not to the whole doc. (The total thing adds up to about
246KB, but it's a bit of a pain to save/print in individual parts.)
Cheers, Phred.
--
ppnerk...@THISyahoo.com.INVALID
Mike Richter
>>
>>
>>>Please can some one post a Active URL on this..
>>
>>TinyURL's have finite life. The link has been posted at my WWW site for
>>some months:
>>
>>Standards Published on Permanence of Electronic Materials
>>http://www.cd-info.com/CDIC/Industry/news/ansi.html
Sorry - grabbed the wrong one. The one you're after is the third on the
Files page:
http://www.itl.nist.gov/div895/carefordisc/disc_care/index.htm
You may find others there of value.
Neil Maxwell
wrote:
>Maybe this file will put an end to so many myths concerning aging DVD,
>CD, etc...
Unfortunately, this paper has very little hard scientific data on CDR
lifetimes behind it, though I believe their recommendations are mostly
valid. Still, they echo many bits of 'net wisdom with anecdotal
roots.
I haven't followed all their references (some clearly aren't worth
it), but the ones I have followed aren't very data-driven, or the
experiments aren't well designed.
The fact is there are no well-designed studies on CDR lifetime
failures that I'm aware of. If anyone's aware of any, I'd love to see
the links.
Neil Maxwell - I don't speak for my employer
smh
Mike Richter, were you born with
"Scam Artist" emblazoned on your face?
--------------------------------------
(Mike Richter, any Material Connection w/ Roxio?)
http://groups.google.com/groups?selm=3F2D8973...@mindspring.com
(Messages 10, 12 -- 34, 54 -- 69)
( No pipsqueaks have been able to prove ANY of the above is a libel )
( -- despite Mikey's supposed to have proof of misquotes! )
======================
From: David Chien
Subject: PC Active Dutch Magazine - CD-R test report, anyone can post?
Date: 8/21/03
http://www.cdfreaks.com/news/7751
Anyone out there with a copy of this Dutch magazine article and can post
the results? (Not a lot of Dutch bookstores here in the US, if you know
what I mean.)
======================
From: "Pking"
Subject: Trouble study on cd's.
Date: 8/25/03
http://groups.google.com/groups?selm=P4d2b.14563$r15.8...@twister.southeast.rr.com
http://www.cdfreaks.com/news/7751
======================
From: "Den"
Subject: How long does CD-R's last
Date: 9/1/03
http://groups.google.com/groups?selm=bj0ig3$ni5$1...@news7.svr.pol.co.uk
Just seen this on the register;
http://www.theregister.co.uk/content/54/32593.html
Is their any guidelines on the lifetime of CD-R's branded and unbranded.
======================
From: (Who Me?)
Subject: Some CDr brands degrade within months article
Date: 9/2/03
http://groups.google.com/groups?selm=5d11faee.03090...@posting.google.com
Some CDr brands degrade within months article
http://theregister.co.uk/content/54/32593.html
======================
MrB
"London Midland & Scotland" <l...@rail.co.uk> wrote in message
news:8qo520pgolhb0q77k...@4ax.com...
> On 5 Feb 2004 11:19:38 -0800, jardin...@yahoo.com (jardinero) wrote:
>
> >Hey, people!
> >
> >
> >For all of us concerned with the longevity of optical disks and the
> >effects of dust, fingerprints, labels, etc. on them, download an
> >excellent pdf file written on the subject.
> >
> >Scientists working on the Digital Preservation Program at the National
> >Institute of Standards and Technology (NIST) have released an
> >excellent 50 page guide ( http://tinyurl.com/2x43f ) on care and
> >handling of CDs and DVDs for long term storage.
>
>
> Is this a Valid URL Link as it does not seem to work.
>
> http://tinyurl.com/2x43f
Toshi1873
jardin...@yahoo.com says...
Posted on /. a week or two ago as well.
http://slashdot.org/article.pl?sid=04/01/24/0054242&mode=nested&tid=137
&tid=198
And it never hurts to add recovery data to the CD/DVD.
lowge...@aol.com
>Unfortunately, this paper has very little hard scientific data on CDR
>lifetimes behind it, though I believe their recommendations are mostly
>valid. Still, they echo many bits of 'net wisdom with anecdotal
>roots.
>
My opinion of this paper is even lower than yours.
Their timeline shows cassettes starting in the early 80s. Early 70s would
be more accurate. They claim punch card were in the 70s when it's a well
known technology from the early part of the century. It omits paper tape
and reel tape and vinyl and acetates and stuff I forgot.
One place says cdrs may use aluminum another place it says the opposite.
The 'solvent' thing is misleading. Water is a solvent. Any solvent dries
quickly and is gone. There's no reference for their caveat.
They claim polycarb absorbs moisture. Really?
Some jewel cases (their favorite) are clearly more dangerous than a paper
sleeve.
They offer data about about dvdr durability yet claim that cdr tests are
being developed. Huh?
I gave this just a fast read and already forgot several other quibbles. But
It's good enough for government work.
Phred
>Neil Maxwell <neil.m...@nospam.intel.com> wrote:
>>Unfortunately, this paper has very little hard scientific data on CDR
>>lifetimes behind it, though I believe their recommendations are mostly
>>valid. Still, they echo many bits of 'net wisdom with anecdotal
>>roots.
>
>My opinion of this paper is even lower than yours.
>They claim polycarb absorbs moisture. Really?
<quoting from:
http://palimpsest.stanford.
edu/byform/mailing-lists/av/2000/08/msg00063.html>
-------------------------------------------------
To: AV-Media...@topica.com
Subject: RE: [AV Media Matters] The Permeability of Polycarbonate (PC)
used in optical co
From: Joseph Wrobel <medi...@kodak.com>
Date: Fri, 25 Aug 2000 14:47:35 -0700
Message-ID: <0.10003996.301819577...@topica.com>
-------------------------------------------------
For those of you who would like to learn more about the diffusion of
water into polycarbonate, I suggest you obtain a copy of the paper I
wrote that discusses the subject in depth: "Ramp profiles for optical
disc incubation", SPIE Vol. 2338 Optical Data Storage, 191-202, 1994.
Ed, you should be aware of this paper as it is referenced in the ANSI
standard for estimating life expectancy of CD-ROM (ANSI/NAPM
IT9.21-1996) and that for CD-R (ANSI/PIMA IT9.27-1999).
The purpose of the paper was to address the changes in polycarbonate
water content that occur as conditions are cycled during the high
temperature, high humidity incubations that are performed in
accelerated keeping studies of optical media using polycarbonate
substrates. As Ed points out, the rate of water diffusion in and out
of the polycarbonate substrate is very different at its two surfaces.
Water diffusion through the metal coated side is essentially nil;
water diffusion through the free polycarbonate surface, though slow,
is appreciable over the duration of an incubation experiment,
especially those run at high temperature.
The problem is not the moisture intake. The saturated moisture
content of polycarbonate at 20C is 0.3%; at 80C it rises only to 0.5%.
The problem is that unless due precautions are taken, when a disc held
at high humidity and high temperature for a long time is introduced
into a room environment, the moisture preferentially diffuses out the
free surface and, as it does, leaves behind a non-uniform distribution
of water in the substrate. Since polycarbonate expands when it picks
up water, the gradient in water content causes the polycarbonate
substrate to symmetrically deform ("bowl") to a spherical surface to
accommodate the gradient in expansion. If the gradient is extreme,
the disc deflection could exceed the CD deflection specification until
the disc equilibrates with the environment. And at room temperature,
this would take a rather long time, up to several days.
</quoting>
For Kodak data, see:
http://www.cd-info.com/CDIC/Technology/CD-R/Media/Kodak.html
Cheers, Phred.
--
ppnerk...@THISyahoo.com.INVALID