Searching \ for '[OT] Is your oldest CD-R still readable?' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/index.htm?key=your+oldest+still
Search entire site for: 'Is your oldest CD-R still readable?'.

Exact match. Not showing close matches.
PICList Thread
'[OT] Is your oldest CD-R still readable?'
2006\01\12@205837 by n Pergola (sent by Nabble.com)

flavicon
face


How old is your oldest recorded CD-R disc?

Is it still readable?


I was amazed at the claims made in this article (see below) without any data to back up the claims:

===========================================
Storage Expert Warns Of Short Life Span For Burned CDs

IBM experts are urging consumers -- and companies -- to consider
magnetic tape storage devices if they want to preserve their digital
content long term.

http://cwflyris.computerworld.com/t/242241/185491/5939/0/

Quotes below are taken from the article mentioned further into this post:

"...burned CDs have a relatively short life span of between two to five years, depending on the quality of the CD..."

"Many of the cheap burnable CDs available at discount stores have a life span of around two years..."

"Some of the better-quality discs offer a longer life span, of a maximum of five years."
===========================================



Obviously no one has a 20- or 30-year old CD-R yet...so there is a lot of speculation out there with regard to shelf-life. I can't believe, and have personally disproved through my own experience with CD-Rs, some of the claims made in that article. I really would like to have seen some data to back up those statements.

The oldest CD-R that I own is a Kodak PhotoCD disc that was professionally produced in September of 1995. After over 10 years, it is still readable. According to the above article, it shouldn't be. I purchased my first CD burner in late 1997. I have numerous CD-Rs burned in 1998 that are still readable.

I'd be interesting to hear if anyone out there has a CD-R older than 10 years and whether anyone has had any of their CD-Rs disc rendered unreadable under "normal" circumstances through the passage of time.

I've also read claims (not in that story listed above) that virgin CD-Rs have a shelf-life, but I have virgin CD-Rs that are over 5 years old that can still be recorded to.

A good read on the care and feeding of optical media is:

Information Technology:
Care and Handling of CDs and DVDs —A Guide for Librarians and Archivists
NIST Special Publication 500-252
Fred R. Byers

If interested, you should be able to find the PDF file with a search engine.

Best regards,

Ken Pergola

P.S. My apologies if this post did not get sorted into the OT category. I don't see an OT option in Nabble so I added '[OT]' in hopes that it would not be posted to the [PIC] category.

--
View this message in context: www.nabble.com/-OT-Is-your-oldest-CD-R-still-readable--t907869.html#a2354218
Sent from the MicroControllers - PIC forum at Nabble.com.

2006\01\12@211638 by Jinx

face picon face
> "...burned CDs have a relatively short life span of between two to
> five years, depending on the quality of the CD..."
>
> "Many of the cheap burnable CDs available at discount stores
> have a life span of around two years..."
>
> "Some of the better-quality discs offer a longer life span, of a
> maximum of five years."

Don't know if I'd go as low as 2 years, but maybe I got lucky. I've
many archive CDs from 4-5 years ago that look fine. I always try
to store CDs in a cool dark place

My oldest audio CD (Broken English by Marianne Faithfull, dated
1979) has holes. Fortunately it did copy (bugger the copyright laws,
I paid for the damn thing)

I tried the same with a friend's Steppenwolf's Greatest Hits, which
is probably early 90s, and absolutely falling to bits at the edges.
Two tracks won't play or copy, one won't play but did copy, the
middle of the disc is OK-ish but degrading

Check out the thread [EE] Obsolete Media of January 2005

2006\01\12@211904 by Mario Mendes

flavicon
face
I burn music compilations on CDs all the time and have been doing so
since 98 since I got my first burner.  Since 98 I've always purchased
the cheapest CDRs available since what I was doing was copying music
onto them and not using them for backups anyway.  One of the very first
music CDs I burned back then can still be played today.  However, I have
had some CDs that were left in the car, like on the front seat that
after getting some direct sunlight along with the high temperatures of a
closed car during a summer afternoon do not play as well today, but I
can still play most of the stuff on them.

I'm sure that quality of the cheap CDR does play a role, but 2 years is
definitely too short from my experience.

I would thing that CDRs that were recorded and erased over a few times
may have their life span shortened, but not write-once-read-many ones,
unless of course, you abuse them, such a leaving them in the full blown
summer sun heat in the car as mine =)


-Mario


{Original Message removed}

2006\01\12@212840 by Juan Cubillo

flavicon
face
2 weeks ago I reinstalled win95 to a pentium 133 pc that I have. The disk is a burned copy from the origina disk that I had. I always make cpies from software that I buy.
So the disk is about 10 years old and works perfectly.
On the other hand I recently bought a tower of cds to burn mp3s. I played the burned disk once. The second time I tried to it wouldn't work...for 100 cds the sam thing happened. Even on diferent computers...
Juan Cubillo

{Original Message removed}

2006\01\12@215543 by Mike Singer

picon face
Ken Pergola wrote:

> IBM experts are urging consumers -- and companies -- to consider
> magnetic tape storage devices if they want to preserve their digital
> content long term.
>
> http://cwflyris.computerworld.com/t/242241/185491/5939/0/

The IBM guy is just a liar in my opinion. To make strong statements
one must provide strong proof. He didn't any.

Mike.

2006\01\12@220530 by Danny Sauer

flavicon
face
Ken wrote regarding '[OT] Is your oldest CD-R still readable?' on Thu, Jan 12 at 20:01:
> How old is your oldest recorded CD-R disc?

I've got CD-Rs that are darn near a decade old, and the only ones that
have failed are ones that failed right away.  As far as I've tested,
anyway. :)  I've actually got more pressed CDs (which aren't covered by
the story) where the aluminum has holes or cracks...

I did some research on this when it started making the rounds a couple
of days ago.  It seems that the CD-R geeks (I didn't know they existed
either) say that the made in Japan disks are the best, while the made
in China are the worst and the made in Taiwan disks are better than
Chinese but still not that great.  The manufacturers change around
without changing their packaging noticably, so you have to check every
time you buy.  Fuji seems to be most consistently made in the Japanese
plant, so that brand is apparently the favorite for when you can't
check the label.  Then there's the Mitsui/mam-a gold subtrate disks
with the phenylcyanine (I hope I spelled that right) chemical layer
for when you really want it to last.  You're looking at about
$2-$3/disk, but they're supposedly the ultimate for longevity.

On any disk, burning at a slower speed seems to increase the
reliability of the burn, as well.  16x is the sweet spot, where the
drives typically go to a constant linear velocity (the inside pits
pass the laser at the same speed as the outer pits) as opposed to a
constant angular velocity (rotational speed is constant, so the outer
bits pass much more quickly than the inner bits).  I've unknowingly
verified that with some cheap media I had before - the CD player in my
car wouldn't read the outer tracks it if I burned at any speed over
16x, but I could read the disk on a computer and in another car fine.
Apparantly better media would result in disks that the same car could
read when burned at 52x.

At least, that's my understanding.  Looking at the packages of disks
around me, the ones that I've had problems with are, in fact, all made
in China, while the made in Japan disks I have all worked well.  I
bought them all before I learned this much, so it's somewhat neat to
see that the seemingly random crud one finds about this kind of thing
online is actually true inthis case. :)

--Danny

2006\01\12@224910 by Herbert Graf

flavicon
face
On Thu, 2006-01-12 at 17:58 -0800, Ken Pergola (sent by Nabble.com)
wrote:
> Obviously no one has a 20- or 30-year old CD-R yet...so there is a lot of speculation out there with regard to shelf-life. I can't believe, and have personally disproved through my own experience with CD-Rs, some of the claims made in that article. I really would like to have seen some data to back up those statements.
>
> The oldest CD-R that I own is a Kodak PhotoCD disc that was professionally produced in September of 1995. After over 10 years, it is still readable. According to the above article, it shouldn't be. I purchased my first CD burner in late 1997. I have numerous CD-Rs burned in 1998 that are still readable.
>
> I'd be interesting to hear if anyone out there has a CD-R older than 10 years and whether anyone has had any of their CD-Rs disc rendered unreadable under "normal" circumstances through the passage of time.
>
> I've also read claims (not in that story listed above) that virgin CD-Rs have a shelf-life, but I have virgin CD-Rs that are over 5 years old that can still be recorded to.

About a year ago I cleaned up some stuff and decided to burn the
contents of all my CDRs to DVD. None more then around 5 years old had
any useful data on them. Note that these had been burned by many
different burners, were of many different brands, and were properly
stored. Oh, and reading the CDRs was tried with three different machine,
spanning two OSs.

CDRs newer then 5 years were in better shape, all newer then 2 years
were perfectly fine, those between 2 and 5 years varied, some had some
useful data, others almost completely fine, others almost completely
gone.

I did tend to notice a few things, mostly the "green" ones faired worse
then the "clear" ones, and name brands tended to be a little better, but
not by much.

All the CDRs in question contained data that wasn't very important (all
my important data has always been backed up in multiple ways on multiple
media), but I was most certainly surprised at how BAD it had gotten.

To that day I had personally doubted the claims people had been making
about longevity of CDR media. Obviously my opinion is vastly different
these days.

Obviously newer writtable media is still an unknown, personally I won't
trust any -R media beyond about a year if the data is valuable to me.

TTYL

-----------------------------
Herbert's PIC Stuff:
http://repatch.dyndns.org:8383/pic_stuff/

2006\01\13@015742 by Ruben Jönsson

flavicon
face
Is there any difference between CD-R and DVD-R regarding this? What about DVD+R
compared to DVD-R?

Regards / Ruben

>
> How old is your oldest recorded CD-R disc?
>
> Is it still readable?

==============================
Ruben Jönsson
AB Liros Electronic
Box 9124, 200 39 Malmö, Sweden
TEL INT +46 40142078
FAX INT +46 40947388
spam_OUTrubenTakeThisOuTspampp.sbbs.se
==============================

2006\01\13@042536 by Alan B. Pearce

face picon face
The problem I have heard with CD-R is that the dye changes that have been
necessary to get the faster writing speeds do not produce long lasting
writes. It may be possible to get a better state change in the dye by
writing at a lower than maximum speed.

The dyes used in older CD-R disks which do not write at the higher speeds
keep their state change better with age.

No actual experience with this, just something that came up on another list
I am on.

2006\01\13@084130 by alan smith

picon face
Friend of mine USED to work at Iomega (makers of the ZIP drive) and told me....that even tho they made at the time, a CD-R, nothing beats magnetic media, either the ZIP drive or tape.  I still use CD and DVD for backups.  I have CD's for instal programs that I used tor rebuild my machines that are 5 or 6 years old, nary a problem.  oops...I'm writing this on Friday/13th  maybe they will all fail today?  :-)

Mike Singer <.....znatokKILLspamspam@spam@gmail.com> wrote:  Ken Pergola wrote:

> IBM experts are urging consumers -- and companies -- to consider
> magnetic tape storage devices if they want to preserve their digital
> content long term.
>
> http://cwflyris.computerworld.com/t/242241/185491/5939/0/

The IBM guy is just a liar in my opinion. To make strong statements
one must provide strong proof. He didn't any.

Mike.

2006\01\13@091724 by Sean Schouten

face picon face
On the subject of backups and failures...

A teacher of mine just recently backed up her important -school- files for
the first time, on to a cd-r and (as a result?) her her computer died the
very next day! Talk about incredible timing..

Backup-voodoo? Who knows...

Sean

2006\01\13@105717 by William Chops Westfield

face picon face
On Jan 13, 2006, at 5:41 AM, alan smith wrote:

> nothing beats magnetic media, either the ZIP drive or tape.

Given my collection of magnetic media (DECTape, 9track tape)
that is nearly or completely unusable due to lack of drive
availability, and widely believed to be likely to shed magnetic
coating like confetti if I ever found a drive to put it on (and
the quoted lifetime is in that 5-10 year range posited for CDR
as well), this does not make me feel very warm or fuzzy :-(

I wonder how external (USB, firewire) laptop disk drives will
hold up in a safe deposit box?

BillW

2006\01\13@111113 by William Couture

face picon face
On Jan 13, 2006, at 5:41 AM, alan smith wrote:

> nothing beats magnetic media, either the ZIP drive or tape.

At work, I'm currently archiving old 5.25" floppies before we don't have
a working drive anymore.

In my experience, 5.25" floppies are VERY stable, better than 3.5"
floppies.

But, somehow, I don't think they will become the archive media
of choice anytime soon...

And, a little more on-topic, my oldest CD-R is about 10 years
and still going strong.  Although I should start doing wholesale
CD copies sometime soon, to make sure my archives are
still OK.  An extra CD or two on a shelf is cheap insurance.

Although, I have found that an old hard drive sitting on a shelf
may be the best way to keep old files.

Bill

--
Psst...  Hey, you... Buddy...  Want a kitten?  straycatblues.petfinder.org

2006\01\13@111436 by Howard Winter

face
flavicon
picon face
Sean,

On Fri, 13 Jan 2006 15:17:24 +0100, Sean Schouten wrote:

> On the subject of backups and failures...
>
> A teacher of mine just recently backed up her important -school- files for
> the first time, on to a cd-r and (as a result?) her her computer died the
> very next day! Talk about incredible timing..
>
> Backup-voodoo? Who knows...

This is *really* unusual - according to Murphy (and my own experience) disks usually fail just *before* you do
a backup!

Cheers,


Howard Winter
St.Albans, England


2006\01\13@111602 by Michael Rigby-Jones

picon face


>-----Original Message-----
>From: piclist-bouncesspamKILLspammit.edu [.....piclist-bouncesKILLspamspam.....mit.edu]
>Sent: 13 January 2006 15:57
>To: Microcontroller discussion list - Public.
>Subject: Re: [OT] Is your oldest CD-R still readable?
>
>
>On Jan 13, 2006, at 5:41 AM, alan smith wrote:
>
>> nothing beats magnetic media, either the ZIP drive or tape.
>
>Given my collection of magnetic media (DECTape, 9track tape)
>that is nearly or completely unusable due to lack of drive
>availability, and widely believed to be likely to shed
>magnetic coating like confetti if I ever found a drive to put
>it on (and the quoted lifetime is in that 5-10 year range
>posited for CDR as well), this does not make me feel very warm
>or fuzzy :-(

I can remember being slightly upset that my collection of Dragon32 software on audio cassette was almost totaly destroyed after being stored in my attic for a few years (which gets pretty hot in summer, and very cold in winter).  Saying magnetic media is more reliable is rather a blanket statement...some of it might be.  Somewhere buried in my father attic is an old handheld magnetic wire recorder, one of the first truly portable dictaphones I guess.  Would be interesting to see if any recognisable audio remains on that!

Regards

Mike

=======================================================================
This e-mail is intended for the person it is addressed to only. The
information contained in it may be confidential and/or protected by
law. If you are not the intended recipient of this message, you must
not make any use of this information, or copy or show it to any
person. Please contact us immediately to tell us that you have
received this e-mail, and return the original to us. Any use,
forwarding, printing or copying of this message is strictly prohibited.
No part of this message can be considered a request for goods or
services.
=======================================================================

2006\01\13@111924 by Michael Rigby-Jones

picon face


>-----Original Message-----
>From: EraseMEpiclist-bouncesspam_OUTspamTakeThisOuTmit.edu [piclist-bouncesspamspam_OUTmit.edu]
>Sent: 13 January 2006 16:11
>To: Microcontroller discussion list - Public.
>Subject: Re: [OT] Is your oldest CD-R still readable?
>
>
>On Jan 13, 2006, at 5:41 AM, alan smith wrote:
>
>> nothing beats magnetic media, either the ZIP drive or tape.
>
>At work, I'm currently archiving old 5.25" floppies before we
>don't have a working drive anymore.
>
>In my experience, 5.25" floppies are VERY stable, better than
>3.5" floppies.

My experience with 3.5" floppies, especialy some of the newer (cheaper) ones is that they are an exercise in frustration and lost data.  I must have binned literaly hundreds of them that refused to format etc.

Mike

=======================================================================
This e-mail is intended for the person it is addressed to only. The
information contained in it may be confidential and/or protected by
law. If you are not the intended recipient of this message, you must
not make any use of this information, or copy or show it to any
person. Please contact us immediately to tell us that you have
received this e-mail, and return the original to us. Any use,
forwarding, printing or copying of this message is strictly prohibited.
No part of this message can be considered a request for goods or
services.
=======================================================================

2006\01\13@112023 by Michael Rigby-Jones

picon face


{Quote hidden}

Murphy currently has a large backlog of bad luck to distribute, sometimes it doesn't arrive on time...

Mike

=======================================================================
This e-mail is intended for the person it is addressed to only. The
information contained in it may be confidential and/or protected by
law. If you are not the intended recipient of this message, you must
not make any use of this information, or copy or show it to any
person. Please contact us immediately to tell us that you have
received this e-mail, and return the original to us. Any use,
forwarding, printing or copying of this message is strictly prohibited.
No part of this message can be considered a request for goods or
services.
=======================================================================

2006\01\13@113402 by William Couture

face picon face
On 1/13/06, Michael Rigby-Jones <RemoveMEMichael.Rigby-JonesTakeThisOuTspambookham.com> wrote:

> >> On the subject of backups and failures...
> >>
> >> A teacher of mine just recently backed up her important
> >-school- files
> >> for the first time, on to a cd-r and (as a result?) her her computer
> >> died the very next day! Talk about incredible timing..
> >>
> >> Backup-voodoo? Who knows...
> >
> >This is *really* unusual - according to Murphy (and my own
> >experience) disks usually fail just *before* you do
> >a backup!
>
> Murphy currently has a large backlog of bad luck to distribute, sometimes it doesn't arrive on time...

Sometimes Murphy gets in Murphy's way...

Bill

--
Psst...  Hey, you... Buddy...  Want a kitten?  straycatblues.petfinder.org

2006\01\13@113514 by Alan B. Pearce

face picon face
>> her computer died the very next day! Talk about incredible timing..
>>
>> Backup-voodoo? Who knows...
>
>This is *really* unusual - according to Murphy (and my own
>experience) disks usually fail just *before* you do
>a backup!

Agreed. The Voodoo doll must have been having a bad day that day.

I have been involved in attempting to recover a system that was backed up on
floppies, and we had a disk failure just as we were installing a brand new
system with a tape drive and attempting to copy the data over ...

2006\01\13@114602 by Howard Winter

face
flavicon
picon face
Bill,

On Fri, 13 Jan 2006 07:57:16 -0800, William "Chops" Westfield wrote:
>...
> I wonder how external (USB, firewire) laptop disk drives will
> hold up in a safe deposit box?

Depends how well insulated it is against a Thermite lance!  :-)

As long as it doesn't get banged-about when the drawer is opened and shut, and that it is allowed plenty of
time to acclimatise before you apply power to it, it should be extremely reliable.  Since the safety deposit
box will form a Faraday shield, and will probably reduce magnetic fields a lot, there is no reason why it
shouldn't last for ever.  For small values of "ever", obviously...

Cheers,


Howard Winter
St.Albans, England


2006\01\13@115235 by Howard Winter

face
flavicon
picon face
Alan,

On Fri, 13 Jan 2006 16:35:10 -0000, Alan B. Pearce wrote:

> I have been involved in attempting to recover a system that was backed up on
> floppies, and we had a disk failure just as we were installing a brand new
> system with a tape drive and attempting to copy the data over ...

Q.E.D. !  :-)

Howard's Law of Backups is "Never have just one copy of anything you want to keep", and in cases like this
where you are overwriting the original (I think that's what you mean?) the one backup isn't enough!  I've seen
this sort of thing happen too often...  the classic was a supposedly experienced IT person who reformatted the
hard drive on a live Novell server (a number of years ago) without either taking a backup of his own, or
checking that the regular overnight backups were working and complete.  It turned out that they weren't, and
his department tried to blame the people who set up the backup scheme...  would you jump out of an aircraft
without checking that you were wearing a parachute, and that you were securely harnessed to it???

Cheers,


Howard Winter
St.Albans, England


2006\01\13@121836 by Alan B. Pearce

face picon face
>Howard's Law of Backups is "Never have just one copy of
>anything you want to keep", and in cases like this where
>you are overwriting the original (I think that's what you
>mean?) the one backup isn't enough!

No, this had a proper grandfather/father/son backup cycle, with weekly
archives etc, all properly set up by the IT section for the customer.

The problem was that the floppies had sector failures when we went to read
them, even though they passed the verify check when written - the write
process did a write of the floppy then a read of the whole floppy to verify
what was just written.

>I've seen this sort of thing happen too often...  the classic
>was a supposedly experienced IT person who reformatted the
>hard drive on a live Novell server (a number of years ago)
>without either taking a backup of his own, or checking that
>the regular overnight backups were working and complete.

<VBG> my boss at the time of the above incident had previously been an
engineer at Burroughs, and he used to relate a story about another engineer
he worked with.

For some reason it had been decided that a disk pack needed formatting on a
live machine. He got everything all organised, and asked the supervisor if
it was OK to go ahead, and he automatically said yes, just as he realised
the engineer was hitting the enter key to start the process realised that
the pack was still live. Result was a 3 day database restore. I do not know
why the operating system allowed him to do such a low level thing on a pack
that was still attached to a data set, but apparently it all turned out a
bit embarrassing.


2006\01\13@122331 by Mario Mendes Jr.

flavicon
face
Pen and paper, people!  Perfect example -> they just found the dead sea
scrolls a short while ago and they can still read it after nearly 2000
years without the need to find a drive that does not exist anymore or
costs a million bucks because it is the only one left in the world that
still works.

A piece or two of carbon paper will give you extra copies just in case one
of your copies gets eaten by moths or chewed on by rodents.

;^)

-Mario

2006\01\13@124150 by alan smith

picon face
wonder how flash drives hold up over time.....I use them to back up my daily work at least.



               
---------------------------------
Yahoo! Photos
Ring in the New Year with Photo Calendars. Add photos, events, holidays, whatever.

2006\01\13@132013 by Jose Da Silva

flavicon
face
On January 13, 2006 09:41 am, alan smith wrote:
> wonder how flash drives hold up over time.....I use them to back up
> my daily work at least.

Read the info related to the microchip 24series flash roms.
That gives you a fairly good idea of what you are dealing with.

2006\01\13@132937 by n Pergola (sent by Nabble.com)

flavicon
face

Hello everyone,

I appreciate everyone's comments and experiences (and everyone's time in writing them). All other very interesting digressions aside, my main problem about all of this is simply about responsible journalism -- this is what drove me to write my original post. (I simply could not believe what I was reading when I have existing proof to refute some of the claims made in the article.) Some people will read that article and accept it as pure truth. To me, it's not about one media type versus another, or backup strategies (whole different topics), it's about specific claims made in the article about CD-R shelf-life/longevity that seemingly went unchecked, and was published anyway.

I think the most astounding thing about all of this is how articles like this can be published when there is clearly evidence that refutes the claims being made. Specifically, let me call attention to the three quotes from the article that I quoted in my original post:

Quotes below are taken from the article:

"...burned CDs have a relatively short life span of between two to five years, depending on the quality of the CD..."

"Many of the cheap burnable CDs available at discount stores have a life span of around two years..."

"Some of the better-quality discs offer a longer life span, of a maximum of five years."

It's just amazing to me that the author could say this when there are many examples of CD-Rs that have clearly surpassed the 5-year mark in terms of longevity and data integrity. It's equally amazing to me that the publishers of the article (not the author) would publish something like this with these claims. To me, the first questions I would ask if I were a publisher of this article would be:

1) Something does not "smell" right here. Where is your data?

2) Why are there many CD-Rs out there older than 5 years that are still perfectly useable?

Someone whose title is a storage expert working at IBM surely must know that saying a life span "of a maximum of five years" is just a wrong statement to make when there is hard and fast evidence to contradict that statement. I'm just wondering if he was misquoted or if the story was edited in some way as to obfuscate his message?

At least one optical media manufacturer uses the phrase "data storage life expectancy" -- the key word is "expectancy". However, in the case of the article's author, I just think it is irresponsible for him to say "two to five years" and "a maximum of five years" with a hint of "certainty". A maximum is strictly a maximum, right?

Maybe I've misinterpreted his claims and have totally missed the point. I surely hope the original author will follow-up and explain why those three statements were made without any data to back it up (or how they were arrived upon), and why those specific CD-R claims were made when there are plenty of examples of existing CD-R media that refute those shelf-life/longevity claims.

Thanks 'Jinx' for posting the old PICList thread topic 'obsolete media' -- that was very interesting -- I had not seen that thread before. In the case of my post, like I previously said, to me it's more of a "journalism thing".

Thank you everyone for your comments and please have a great weekend! :)

Best regards,

Ken Pergola

--
View this message in context: www.nabble.com/-OT-Is-your-oldest-CD-R-still-readable--t907869.html#a2366940
Sent from the MicroControllers - PIC forum at Nabble.com.

2006\01\13@140101 by Peter

picon face

On Thu, 12 Jan 2006, Ken Pergola (sent by Nabble.com) wrote:

>
> How old is your oldest recorded CD-R disc?
>
> Is it still readable?

I have 5-6 year old disks from my current burner and they are ok. I
know people who actually have 10 year old ones (at the time a burner was
premium $$$ hardware) and they also work. I also know that DAT backup
tape is sort of self erasing but DLT/SLT lasts forever (certainly
longer than 10 years).

Peter

2006\01\13@141725 by Peter
picon face


On Fri, 13 Jan 2006, Sean Schouten wrote:

> On the subject of backups and failures...
>
> A teacher of mine just recently backed up her important -school- files for
> the first time, on to a cd-r and (as a result?) her her computer died the
> very next day! Talk about incredible timing..
>
> Backup-voodoo? Who knows...

If it would be real vodoo then the data on the cd will be unreadable
when attempting restoration ... Murphy never sleeps

Peter

2006\01\13@142133 by Peter

picon face

On Fri, 13 Jan 2006, William Chops Westfield wrote:

> On Jan 13, 2006, at 5:41 AM, alan smith wrote:
>
>> nothing beats magnetic media, either the ZIP drive or tape.
>
> Given my collection of magnetic media (DECTape, 9track tape)
> that is nearly or completely unusable due to lack of drive
> availability, and widely believed to be likely to shed magnetic
> coating like confetti if I ever found a drive to put it on (and
> the quoted lifetime is in that 5-10 year range posited for CDR
> as well), this does not make me feel very warm or fuzzy :-(
>
> I wonder how external (USB, firewire) laptop disk drives will
> hold up in a safe deposit box?

Laptop disk drives have a problem: lubricant. Non-spinning laptop drives
that are stored for a long time tend to have polymerized oil in the
spindle bearing. They cannot spin up to rated rpm. Some delicate surgery
can revive them but it requires opening the bearing. After that using
the drive is russian roulette.

Peter

2006\01\13@142236 by Peter

picon face


On Fri, 13 Jan 2006, William Couture wrote:

> On Jan 13, 2006, at 5:41 AM, alan smith wrote:
>
>> nothing beats magnetic media, either the ZIP drive or tape.
>
> At work, I'm currently archiving old 5.25" floppies before we don't have
> a working drive anymore.
>
> In my experience, 5.25" floppies are VERY stable, better than 3.5"
> floppies.

I have had both 5.25 and 3.5 floppies go bad (repeatedly). Good makes,
like Nashua and BASF too.

Peter

2006\01\13@142528 by Peter

picon face


> My experience with 3.5" floppies, especialy some of the newer
> (cheaper) ones is that they are an exercise in frustration and lost
> data.  I must have binned literaly hundreds of them that refused to
> format etc.

One of the tricks with floppies is to bulk erase them before formatting.
The high density heads of modern drives have narrow tracks and are
unable to erase and format factory formatted floppies. A bulk eraser is
a box with a power cord and a slot in it. I do not know if the modern
ones use the 'old' style electromagnet. I think not, the field must be
extremely strong to erase a modern floppy. But after that you will be
able to format it ok.

Peter

2006\01\13@142722 by Herbert Graf

flavicon
face
On Fri, 2006-01-13 at 16:52 +0000, Howard Winter wrote:
> Alan,
>
> On Fri, 13 Jan 2006 16:35:10 -0000, Alan B. Pearce wrote:
>
> > I have been involved in attempting to recover a system that was backed up on
> > floppies, and we had a disk failure just as we were installing a brand new
> > system with a tape drive and attempting to copy the data over ...
>
> Q.E.D. !  :-)
>
> Howard's Law of Backups is "Never have just one copy of anything you want to keep", and in cases like this
> where you are overwriting the original (I think that's what you mean?) the one backup isn't enough!  

Well Herbert's law of backups is VERY similar, but a little more
involved:

1. Never have just one generation of backup
2. Never restrict critical backups to the same media
3. NEVER keep all backups in the same place

The way I do things I use DVD-Rs and hard drives for backup, and I have
copies of my backups at work as well.

Using these kinds of rules is great, but perhaps the most obvious and
least followed rule is: MAKE BACKUPS.

You can't imagine how many times a family member or friend has come to
me for help with a deleted file or corrupted disk, and the response to:
do you have a backup? is: no.

TTYL

-----------------------------
Herbert's PIC Stuff:
http://repatch.dyndns.org:8383/pic_stuff/

2006\01\13@143522 by Herbert Graf

flavicon
face
On Fri, 2006-01-13 at 09:41 -0800, alan smith wrote:
> wonder how flash drives hold up over time.....I use them to back up my daily work at least.

Not sure about "over time, stored in a locked safe", but I know for
daily use they don't last more then about 2 years.

I've had two USB flash drives fail on me. Both with the same symtom:
failed to enumerate.

TTYL

-----------------------------
Herbert's PIC Stuff:
http://repatch.dyndns.org:8383/pic_stuff/

2006\01\13@145629 by Mario Mendes Jr.

flavicon
face
> Laptop disk drives have a problem: lubricant. Non-spinning laptop drives
> that are stored for a long time tend to have polymerized oil in the
> spindle bearing. They cannot spin up to rated rpm. Some delicate surgery
> can revive them but it requires opening the bearing. After that using
> the drive is russian roulette.

This is (or was, since it's been a while since I ran into this) a problem
with all kinds of drives, not just laptop ones, that are kept on for
extended periods of time such as in servers or desktops with the power
management features turned off.  I've worked with servers that were on for
periods of over a year and when turned off for maintenace I had to pull
out the drive and "carefully" smite them on the sides to get the heads
untuck.  The explanation from the manufacturer was that the polymer used
on the heads to keep them from scratching the drive in case of light
contact while the platers were spinning, would heat up and become sticky
causing the heads to stick once the heads were parked.

While the head sticking in park probably won't demage the disk or cause
data loss, hitting the drive could end up demaging it.  Moral of the
story: don't just take a drive from a computer and store it, you should
first probably copy the data to a new drive and store the new one.


-Mario

2006\01\13@153316 by William Chops Westfield

face picon face
On Jan 13, 2006, at 11:27 AM, Herbert Graf wrote:

> Using these kinds of rules is great, but perhaps the most obvious and
> least followed rule is: MAKE BACKUPS.
>
Indeed.  Many people have nothing.  I'm not as careful as I
should be, but I usually have at least:

1) Backup documents to zip file on the same disk.
2) backup partition to other partition (preferably another disk)
   on the same computer.
3) backup stuff from one computer to other local computers.
4) backup stuff to external drives and media.

Alas, without more careful organization than I seem to be capable
of, this makes restores somewhat ... disorganized.  I am pretty
sure I can get back a copy of a particular document, but I am not
so sure that I could reliably get back the most recent form of the
document (it WOULD be on one of the backup media, but I wouldn't
be sure which one was most recent.)

The other thing to realize is that actual user-created content
that MUST be backed up tends to be pretty small.  My several
years worth of little Eagle projects zips down to less than 20Mbyte,
so a flash drive makes fine backup storage.  Even the voluminous
work-related-maybe-should-be-saved email archives tend to run less
than 100Mbyte per year.  (remember, 1Mbyte of text is about an
average-sized novel...) (The photo and video files are getting
problematic, though. Sigh.)

BillW

2006\01\13@154015 by Herbert Graf

flavicon
face
On Fri, 2006-01-13 at 12:31 -0800, William Chops Westfield wrote:
> The other thing to realize is that actual user-created content
> that MUST be backed up tends to be pretty small.  My several
> years worth of little Eagle projects zips down to less than 20Mbyte,
> so a flash drive makes fine backup storage.  Even the voluminous
> work-related-maybe-should-be-saved email archives tend to run less
> than 100Mbyte per year.  (remember, 1Mbyte of text is about an
> average-sized novel...) (The photo and video files are getting
> problematic, though. Sigh.)

My backups used to span only a few tens of MBs. These days a backup
takes up many GBs. The reason? Photos. I take alot of photos, and
they're all quite important to me, so they're one of the first things I
back up.

Aside from that, yes, probably 100MB would cover it, although some
powerpoint things get REALLY big sometimes for little reason...

TTYL

-----------------------------
Herbert's PIC Stuff:
http://repatch.dyndns.org:8383/pic_stuff/

2006\01\13@163121 by Jinx

face picon face
> The other thing to realize is that actual user-created content
> that MUST be backed up tends to be pretty small

I feel a lot better with a USB memory stick (this one is a 512MB
but 64MB would do just as well, and they're cheap) attached for
saving .asm files, MPLAB projects etc, as well as to this HDD,
and on the networked #2 machine and to CD less often

As a victim of Murphy too many times in the past (particularly
HDD failures at very inconvenient moments), I'm determined
to not being caught out again (famous last words) and not have
to back-engineer my own work or re-write it. Work files are
the highest priority to back up

Bulk stuff downloaded off the web (pdfs, exes etc) that didn't
take any effort, not too worried about losing, although being on
dial-up, any download that took a "significant" time to do goes
straight to some sort of immediate back-up and CD

2006\01\13@172312 by Jinx

face picon face
> disks usually fail just *before* you do a backup !

I haven't had a drive fail for a few years now, touch wood,
and talking about it gives me the willies, but the last HDD
that failed on me actually waited until I stepped out of the
house to go and buy a 10-pack of CDs to finish my back-
up. When I got back just a few minutes later, there was just
a black screen. Hard drives are bastards ;-)) And cunning
too

2006\01\13@183650 by Marcel Birthelmer

picon face
For disk failure reasons, I usually just buy double the drives I would
normally have and raid-1 them in software. It's a negligible performance hit
for writing, a small speed-up for reading, and the ease of mind that a bad
drive won't make you lose data. Of course, it doesn't protect you from
accidentally deleting stuff or whatever.
- Marcel

On 1/13/06, Jinx <spamBeGonejoecolquittspamBeGonespamclear.net.nz> wrote:
>
> > disks usually fail just *before* you do a backup !
>
> I haven't had a drive fail for a few years now, touch wood,
>

2006\01\13@202702 by Neil Cherry

picon face
I just checked a CD that is date January 1994 (it's a Linux CD) and
it reads just fine! It had a coating of dust on it I had to deal
with (I'm very allergic to dust). But I only cleaned the dust off.

--
Linux Home Automation         Neil Cherry       TakeThisOuTncherryEraseMEspamspam_OUTlinuxha.com
http://www.linuxha.com/                         Main site
http://linuxha.blogspot.com/                    My HA Blog
http://home.comcast.net/~ncherry/               Backup site

2006\01\13@203205 by Jose Da Silva

flavicon
face
On January 13, 2006 11:00 am, Peter wrote:
> I also know that DAT
> backup tape is sort of self erasing but DLT/SLT lasts forever
> (certainly longer than 10 years).

Not really self-erasing, but getting changed due to the earth's magnetic
field. I recall reading a manufacturer's label as saying floppy disks
good for about 5 years due to earth's magnetic field.
I'm guessing the DLT tapes are stored in a metalic box, giving them 10
years.

Storing floppy disks next to monitors is also not a good idea, but then
there are the real geniuses in the community who store their floppy
disks using magnets to hold them to the fridge, in which case the
floppy disks were found to be faulty because they always seemed
corrupt.  ;-)

2006\01\13@205542 by Xiaofan Chen

face picon face
On 1/14/06, Neil Cherry <RemoveMEncherryspamTakeThisOuTcomcast.net> wrote:
> I just checked a CD that is date January 1994 (it's a Linux CD) and
> it reads just fine! It had a coating of dust on it I had to deal
> with (I'm very allergic to dust). But I only cleaned the dust off.
>

CD-R is very different from CD. Good quality CD can be stored
quite long. Even Good CD-R can not be stored for too long.

Quite some of my CD-R dated year 2000 can not be read any more.
But they may not be that high quality.

Regards,
Xiaofan

2006\01\13@213836 by Jim Korman

flavicon
face
William Chops Westfield wrote:
> On Jan 13, 2006, at 11:27 AM, Herbert Graf wrote:
>
>
>>Using these kinds of rules is great, but perhaps the most obvious and
>>least followed rule is: MAKE BACKUPS.
>>
>
> Indeed.  Many people have nothing.  I'm not as careful as I
> should be, but I usually have at least:
>
> 1) Backup documents to zip file on the same disk.
<snip>
Question - Do you really want to zip an archive?
Makes it damn hard to do searches later!

<Additional>
Just as a test I grabbed my old Borland Delphi 1.0 CD
(Circa 1995) and opened a few files at random. No problems
at all.

All of my audio CDs (dating back to 1984) are in great shape and
at least 70 of those were purchased prior to 1986.

I've never had a single CD failure yet! (Knocking on wood)

Jim

2006\01\13@215209 by James Newton, Host

face picon face
> <Additional>
> Just as a test I grabbed my old Borland Delphi 1.0 CD (Circa
> 1995) and opened a few files at random. No problems at all.
>
> All of my audio CDs (dating back to 1984) are in great shape
> and at least 70 of those were purchased prior to 1986.
>
> I've never had a single CD failure yet! (Knocking on wood)

No, no... This is about /writable/ CDs. The ones that are stamped out at the
factory are safe. It's the one you burn yourself that are 'iffy. Maybe. I've
got some that are several years old and still readable. But I also have some
that are a few years old and NOT readable.

---
James Newton: PICList webmaster/Admin
jamesnewtonEraseMEspam.....piclist.com  1-619-652-0593 phone
http://www.piclist.com/member/JMN-EFP-786
PIC/PICList FAQ: http://www.piclist.com


2006\01\13@224302 by andrew kelley

picon face
The Iomega cds are not great at all, I've had many, less than a year
old, all the coating flakes right off the top of the cd.. Memorex, I
have a couple cds from about 2000 and those read just fine.. And to
boot they are a bit scratched up due to how I stored them (in a CD
stack).

andrew

2006\01\13@232954 by Mike Singer

picon face
andrew kelley wrote:
>.. Memorex, I have a couple cds from about 2000
> and those read just fine.. And to boot they are a
> bit scratched up due to how I stored them (in a CD
> stack).

Memorex rocks:

http://www.all-about-storage.com/memorex_adds_24_karat_gold_to_its_longest_lasting_archival_grade_cd_and_dvd_gga.aspx

Memorex Adds 24-Karat Gold to Its Longest Lasting, Archival Grade CD
and DVD Media

6 January 2006

Memorex, ... brings the durability and longevity of 24-karat gold to
its industry-leading family of recordable media. Memorex combines a
24-karat gold reflective layer, high performance dye and its
innovative DuraLayer(TM) scratch-resistant technology to create
Memorex Pro Gold Archival CD and DVD Media.

... These innovative discs are proven to last up to six times longer
than traditional media with a CD archival life of up to 300 years and
a DVD archival life of up to 100 years. Laboratory tests prove Memorex
Pro Gold Media to be resistant to the effects of rapid, artificial
aging such as ultraviolet light, heat and humidity exposure thanks in
part to gold's inert characteristics that prevent oxidation, a common
cause of failure for most recordable media during long-term storage.

Pricing and Availability  Memorex Pro Gold Archival CD and DVD media
will be available at several major retailers this April. Suggested
retail prices for CD-R will be $11.99 USD for a three-pack with
storage cases and $19.99 USD for a five-pack with storage cases.
Suggested retail prices for DVD-R will be $14.99 USD for a three-pack
with storage cases and $24.99 USD for a five-pack with storage cases.

-------------------------------

Mike

2006\01\13@234230 by Mike Singer

picon face
Herbert Graf wrote:
> Well Herbert's law of backups is VERY similar, but a little more
> involved:
>
> 1. Never have just one generation of backup
> 2. Never restrict critical backups to the same media
> 3. NEVER keep all backups in the same place

I would definitely add:

Don't store big files unsplitted. When one chunk of a file fails you
could still use other chunks getting the broken one from another copy.

Mike

2006\01\13@235643 by Danny Sauer

flavicon
face
Mike wrote regarding 'Re: [OT] Is your oldest CD-R still readable?' on Fri, Jan 13 at 22:44:
> Don't store big files unsplitted. When one chunk of a file fails you
> could still use other chunks getting the broken one from another copy.

If you wanna recover from chunks of files missing, look into par -
http://parchive.sourceforge.net/.  Sure, it was developed to help
recover broken unsenet binaries, but it's good for CDs, too.

--Danny

2006\01\14@035332 by Peter Todd

picon face
On Fri, Jan 13, 2006 at 10:24:54AM -0800, Jose Da Silva wrote:
> On January 13, 2006 09:41 am, alan smith wrote:
> > wonder how flash drives hold up over time.....I use them to back up
> > my daily work at least.
>
> Read the info related to the microchip 24series flash roms.
> That gives you a fairly good idea of what you are dealing with.

Care to give a url for that?

Flash longetivity is a very important issue for me. All my art has pic
chips in it and I'd rather the flash holding the programs not die in 20
years...

--
EraseMEpetespampetertodd.ca http://www.petertodd.ca

2006\01\14@041359 by Peter Todd

picon face
On Fri, Jan 13, 2006 at 04:52:33PM +0000, Howard Winter wrote:
> Alan,
>
> On Fri, 13 Jan 2006 16:35:10 -0000, Alan B. Pearce wrote:
>
> > I have been involved in attempting to recover a system that was backed up on
> > floppies, and we had a disk failure just as we were installing a brand new
> > system with a tape drive and attempting to copy the data over ...
>
> Q.E.D. !  :-)
>
> Howard's Law of Backups is "Never have just one copy of anything you want to keep", and in cases like this
> where you are overwriting the original (I think that's what you mean?) the one backup isn't enough!  I've seen
> this sort of thing happen too often...  the classic was a supposedly experienced IT person who reformatted the
> hard drive on a live Novell server (a number of years ago) without either taking a backup of his own, or
> checking that the regular overnight backups were working and complete.  It turned out that they weren't, and
> his department tried to blame the people who set up the backup scheme...  would you jump out of an aircraft
> without checking that you were wearing a parachute, and that you were securely harnessed to it???

Definetely... I like my backup system quite a bit... I use Linux so
these commands may sound a bit foreign, but here it goes...

First of all, I have three seperate "groups" of computers, work, my
server, and my laptop. My files are seperated into two groups, d and m.
d is for data that I created myself, and *really* don't want to loose. m
is for data that other people created, like data sheets, music, videos
etc. The latter I can lose and it's just a financial hit. (I buy mp3s
from bleem.com, and I rip every cd I buy and only keep the mp3s!) d is
1gb in size, m is 8gb.

Those two directories get automatically synchronized between those three
groups of computers, work, server, laptop. So I've automatically got
three backups there, in a minimum of two places. (my apartment and work)
Often this is three, as I usually have my laptop with me.

The work computer is automatically backed up every few hours to a backup
server at work. So my data is backed up again. This is done
automatically by a program called rdiff-backup This gives me incremental
backups, so if I delete something, and find out in three months, I can
restore it. I keep the increments for 6 months. The drive holding the
data is a raid1 mirror, so there's another backup right there.

I also manually backup the work computers to an external harddrive,
which I store at my apartment. So I've got a full, manually checked,
backup every month or so. (I tend to forget!) This backup is a mirror of
the above server's backup drive, so it's also got 6 month increments,
often as much as 9 months old. (assuming I forget for 3 months)

Finally I also rent out a virtual server somewhere in the us from
http://www.unixshell.com These guys are great, they use virtualization software
to make virtual servers out of extremely fast and large Linux boxes. So
they take one big server, say a quad processor Athlon monster with gobs
of ram and hd space, and rent you a virtual server with 96mb of ram, and
3gigs of hd space for $15 a month. So I've got one of those and share it
with my boss. Both are personal directories are automatically backed up
to that server every night, again with rdiff-backup. I set this up
recently, so I've got 4 months of increments there. unixshell also allow
you to make a backup of your server, which I do whenever I make any
configuration changes, in case I fuck up and need to quickly restore my
setup. So that's another backup.

I fairly regularly test all of this, usually after deleting a file...

All in all, 8 backups of my data in three physical places, often four.
With increments going back at least 6 months. Overkill? Yeah, probably.
But it takes so little work once it's setup that I don't care. Doesn't
even cost anything, as my boss pays for that $15 account, and I had more
than enough spare harddrive space everywhere.

I anyone wants any further technical details, like scripts, just ask.

--
RemoveMEpeteEraseMEspamEraseMEpetertodd.ca http://www.petertodd.ca

2006\01\14@041823 by Jinx

face picon face

> > Read the info related to the microchip 24series flash roms.
> > That gives you a fairly good idea of what you are dealing with.
>
> Care to give a url for that?

It's on the front page of all PIC datasheets

"Flash/data EEPROM retention :  > 40 years"

2006\01\14@044412 by Peter Todd

picon face
On Sat, Jan 14, 2006 at 10:18:24PM +1300, Jinx wrote:
>  
> > > Read the info related to the microchip 24series flash roms.
> > > That gives you a fairly good idea of what you are dealing with.
> >
> > Care to give a url for that?
>
> It's on the front page of all PIC datasheets
>
> "Flash/data EEPROM retention :  > 40 years"

Doh! I must have looked at that a thousand times by now... Thanks!

That said, do you know of any more indepth discussion of this? Like how
does temperature, usage, etc. affect this retention time. Where does
that figure come from? I know it must be a calculated value based on
physical models, but what's the model? (roughly speaking)

If it's an MTBF it'd be a much different meaning of course. Can't
imagine it is, I hope!

--
RemoveMEpetespam_OUTspamKILLspampetertodd.ca http://www.petertodd.ca

2006\01\14@051953 by Jinx

face picon face
> > "Flash/data EEPROM retention :  > 40 years"
>
> Doh! I must have looked at that a thousand times by now... Thanks!
>
> That said, do you know of any more indepth discussion of this?

There are quite a few AN papers on EEPROMs eg,

http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=2048

175kB

http://ww1.microchip.com/downloads/en/AppNotes/01019A.pdf

130kB

http://ww1.microchip.com/downloads/en/AppNotes/00537.pdf

60kB

http://ww1.microchip.com/downloads/en/AppNotes/00562.pdf

64kB

http://ww1.microchip.com/downloads/en/AppNotes/00572.pdf

2006\01\14@104621 by olin piclist

face picon face
Neil Cherry wrote:
> I just checked a CD that is date January 1994 (it's a Linux CD) and
> it reads just fine! It had a coating of dust on it I had to deal
> with (I'm very allergic to dust). But I only cleaned the dust off.

I just looked around and found an archive of images from 1997.  This was
written on a Kodak gold CD-R which were touted to be good for 100 years back
then.  Everything I looked at checked out fine.

As an aside, here is a computer graphics trivia challenge.  Who can identify
the two images copied from this CD to http://www.embedinc.com/temp/q1.tif
and http://www.embedinc.com/temp/q2.tif?  Those of you who had a somewhat
direct connection, like DT, should give others a chance to scratch their
heads for a while first.


******************************************************************
Embed Inc, Littleton Massachusetts, (978) 742-9014.  #1 PIC
consultant in 2004 program year.  http://www.embedinc.com/products

2006\01\14@104749 by olin piclist

face picon face
Jose Da Silva wrote:
> Storing floppy disks next to monitors is also not a good idea, but
> then there are the real geniuses in the community who store their
> floppy disks using magnets to hold them to the fridge, in which case
> the floppy disks were found to be faulty because they always seemed
> corrupt.  ;-)

Probably caused by the magnetic fields from the batteries in the fridge
wrapped in aluminum foil  ;-)


******************************************************************
Embed Inc, Littleton Massachusetts, (978) 742-9014.  #1 PIC
consultant in 2004 program year.  http://www.embedinc.com/products

2006\01\14@114145 by n Pergola (sent by Nabble.com)

flavicon
face



Olin Lathrop wrote:

===
...Who can identify
the two images copied from this CD to http://www.embedinc.com/temp/q1.tif
and http://www.embedinc.com/temp/q2.tif?...
===

Hi Olin,

My best guess is that these images might have been created on an Apollo workstation (since both you and Dave worked there in the past, correct?).

Beyond that, my curiosity got the better of me and I cheated and found the answers directly in the TIFF files themselves. I won't give it away though...people can take a peek if they want to.

I always love to see computer-generated graphics so please come on back and share further information about these images. I'll never forget the time I saw an image of King Tut's mask on a Commodore Amiga many years ago (pretty amazing -- to me at least -- compared to the computer graphics I had seen on other computers I had experienced at the time).

Best regards,

Ken Pergola


--
View this message in context: www.nabble.com/-OT-Is-your-oldest-CD-R-still-readable--t907869.html#a2379845
Sent from the MicroControllers - PIC forum at Nabble.com.

2006\01\14@115912 by David VanHorn

picon face
I've heard a number of things about magnetic media slowly going bad from
external fields, but it's not true.

Unless you exceed a certain minimum field strength, you won't affect the
data.
This can be shown by taking two credit cards and rubbing the magnetic strips
together. Myth says that this will erase them,. but the fact is that the
residual magnetism in any media has to be less than the threshold to change
that same media.

Now the oxide may fall off because the binder goes bad, or the mylar may get
brittle with age, but that's a different story.

I've seen people flip out over a megnet used to hold a note on a PC case,
not realizing that there's a set of magnets far more powerful, inside every
hard drive, right next to the platters.

2006\01\14@120021 by n Pergola (sent by Nabble.com)

flavicon
face


I just wanted to share a nice document I found (after seeing Mike Singer's post regarding Memorex). Perhaps many of you have seen this document already but if not...

Memorex has a technical and well-written white paper entitled "Reference Guide for Optical Media".

http://www.memorex.com/html/white_papers_one.php?WP_SID=1

One interesting quote (to me) from the white paper regarding CD-RW media is:

"CD-RW—should last at least as long as CD-Rs, perhaps longer. CD-RW discs have the reputation of being unstable, but factors such as packet-writing complexities and incompatibilities, varying laser spot geometries from different drives, and file corruptions are more to blame for the difficulties than the design or materials of the discs."

For me, this document is a keeper -- I briefly skimmed though some sections, but from what I have read carefully, I thought it was very informative, detailed, and interesting.

Also, an interesting tidbit is the Greek reference behind the naming of 'phthalocyanine' as in 'phthalocyanine dye' (bottom of page 25).

There's tons of infomation out there regarding this thread -- fascinating stuff! :)

Best regards,

Ken Pergola



--
View this message in context: www.nabble.com/-OT-Is-your-oldest-CD-R-still-readable--t907869.html#a2380040
Sent from the MicroControllers - PIC forum at Nabble.com.

2006\01\14@121618 by Brady Small

flavicon
face
Mind's Eye? that video that was all computer rendered graphics set to music?

Brady



{Quote hidden}

> --

2006\01\14@122054 by olin piclist

face picon face
Ken Pergola (sent by Nabble.com) wrote:
> ...Who can identify
> the two images copied from this CD to
> http://www.embedinc.com/temp/q1.tif
> and http://www.embedinc.com/temp/q2.tif?...
>
> My best guess is that these images might have been created on an
> Apollo workstation (since both you and Dave worked there in the past,
> correct?).

Yes you did figure out a lot of stuff, including that DT referred to Dave
Tweed and that both of us worked at Apollo, although I don't remember
running into Dave while I worked there.

However, I was looking for more of a computer graphics history answer that
would be relevant to others.  What are these images?  When were they made,
and why?  Why are they special in a computer graphics historical context?


******************************************************************
Embed Inc, Littleton Massachusetts, (978) 742-9014.  #1 PIC
consultant in 2004 program year.  http://www.embedinc.com/products

2006\01\14@122332 by olin piclist

face picon face
Brady Small wrote:
> Mind's Eye?

You may be thinking of the right thing, but that answer is not correct.

> that video that was all computer rendered graphics

Yes, but there's more.

> set to music?

It may have been.  I don't remember.  That wasn't the salient point though.

******************************************************************
Embed Inc, Littleton Massachusetts, (978) 742-9014.  #1 PIC
consultant in 2004 program year.  http://www.embedinc.com/products

2006\01\14@123751 by n Pergola (sent by Nabble.com)

flavicon
face



Olin Lathrop wrote:

===
However, I was looking for more of a computer graphics history answer that
would be relevant to others.  What are these images?  When were they made,
and why?  Why are they special in a computer graphics historical context?
===

Hi Olin,

Just throwing out a guess to one of your questions:

Are these an early example of 'ray tracing' techniques?

Best regards,

Ken Pergola





--
View this message in context: www.nabble.com/-OT-Is-your-oldest-CD-R-still-readable--t907869.html#a2380491
Sent from the MicroControllers - PIC forum at Nabble.com.

2006\01\14@142610 by Peter

picon face


On Fri, 13 Jan 2006, Mario Mendes Jr. wrote:

> Pen and paper, people!  Perfect example -> they just found the dead sea
> scrolls a short while ago and they can still read it after nearly 2000
> years without the need to find a drive that does not exist anymore or
> costs a million bucks because it is the only one left in the world that
> still works.

Correction: they just found some of the dead sea scrolls a couple of
years ago, and they are still trying to decipher parts thereof. Copper
scrolls did not fare much better.

My advice: clay tables. modifying a Braille or impact printer to print
on (thick) clay paper and then firing it should be perfect. And don't
drop the fired tables. ;-)

Peter

2006\01\14@144002 by olin piclist

face picon face
Ken Pergola (sent by Nabble.com) wrote:
> Are these an early example of 'ray tracing' techniques?

The pictures are ray traced and that is relevant, but there were plenty of
other ray traced pictures around at the time.  Ray tracing by itself is not
what makes these pictures historic.


******************************************************************
Embed Inc, Littleton Massachusetts, (978) 742-9014.  #1 PIC
consultant in 2004 program year.  http://www.embedinc.com/products

2006\01\14@151556 by n Pergola (sent by Nabble.com)

flavicon
face



Olin Lathrop wrote:

===
...makes these pictures historic...
===

Hi Olin,

Were these stills from a live VR (Virtual Reality) demonstration at SIGGRAPH or something? Virtual reality seemed to be the latest buzzword back then (to the best of my recollection).

Best regards,

Ken Pergola


--
View this message in context: www.nabble.com/-OT-Is-your-oldest-CD-R-still-readable--t907869.html#a2382475
Sent from the MicroControllers - PIC forum at Nabble.com.

2006\01\14@152820 by Marcel Duchamp

picon face
Olin Lathrop wrote:
>
> As an aside, here is a computer graphics trivia challenge.  Who can identify
> the two images copied from this CD to http://www.embedinc.com/temp/q1.tif
> and http://www.embedinc.com/temp/q2.tif?  Those of you who had a somewhat
> direct connection, like DT, should give others a chance to scratch their
> heads for a while first.

I've scratched my head to no avail.  The two tifs look very familiar to
me... but I just can't place them.  The memory of them is definately
from several years ago.  It seems to me that I either viewed an
animation including those scenes or played a video game with same.
???

2006\01\14@154613 by olin piclist

face picon face
Ken Pergola (sent by Nabble.com) wrote:
> Were these stills from a live VR (Virtual Reality) demonstration at
> SIGGRAPH or something?

No, this didn't have anything to do with "Virtual Reality".

> Virtual reality seemed to be the latest
> buzzword back then (to the best of my recollection).

It depends on when you think "back then" is.

I'll give you another hint.  The year was 1985.

******************************************************************
Embed Inc, Littleton Massachusetts, (978) 742-9014.  #1 PIC
consultant in 2004 program year.  http://www.embedinc.com/products

2006\01\14@154743 by olin piclist

face picon face
Marcel Duchamp wrote:
> It seems to me that I either viewed an animation including those
> scenes or played a video game with same.

The former is a distinct possibility.

******************************************************************
Embed Inc, Littleton Massachusetts, (978) 742-9014.  #1 PIC
consultant in 2004 program year.  http://www.embedinc.com/products

2006\01\14@163602 by Dave Lag

picon face
Mario Mendes Jr. wrote:
> This is (or was, since it's been a while since I ran into this) a problem
> with all kinds of drives, not just laptop ones, that are kept on for
> extended periods of time such as in servers or desktops with the power
> management features turned off.  I've worked with servers that were on for
> periods of over a year and when turned off for maintenace I had to pull
> out the drive and "carefully" smite them on the sides to get the heads
> untuck.....

.............
> -Mario

Indeed, I have a stack of IBM 2-4gig SCSIs that came from servers.
Everyone needs a smack upside the head to spin up.
D

2006\01\14@181814 by Peter Todd

picon face
On Sat, Jan 14, 2006 at 03:46:10PM -0500, Olin Lathrop wrote:
> Ken Pergola (sent by Nabble.com) wrote:
> > Were these stills from a live VR (Virtual Reality) demonstration at
> > SIGGRAPH or something?
>
> No, this didn't have anything to do with "Virtual Reality".
>
> > Virtual reality seemed to be the latest
> > buzzword back then (to the best of my recollection).
>
> It depends on when you think "back then" is.
>
> I'll give you another hint.  The year was 1985.

Oh! I know exactly why they are so earthshatteringly historic!

I was born! :P

--
RemoveMEpeteKILLspamspampetertodd.ca http://www.petertodd.ca

2006\01\14@182229 by Peter Todd

picon face
On Sat, Jan 14, 2006 at 09:26:06PM +0200, Peter wrote:
>
>
> On Fri, 13 Jan 2006, Mario Mendes Jr. wrote:
>
> > Pen and paper, people!  Perfect example -> they just found the dead sea
> > scrolls a short while ago and they can still read it after nearly 2000
> > years without the need to find a drive that does not exist anymore or
> > costs a million bucks because it is the only one left in the world that
> > still works.
>
> Correction: they just found some of the dead sea scrolls a couple of
> years ago, and they are still trying to decipher parts thereof. Copper
> scrolls did not fare much better.
>
> My advice: clay tables. modifying a Braille or impact printer to print
> on (thick) clay paper and then firing it should be perfect. And don't
> drop the fired tables. ;-)

Hmm... Why not simply print it on stainless steel sheet? Stainless for
the most part doesn't rust if it's just sitting in an normal air
atmosphere. It's even a big part of current plans for long-term nuclear
waste storage.

I'd say laser etch, or CNC route, big sheets of the stuff, 1/8th thick.
Expensive as hell, but it'd probably be much easier than handling clay
tablets. I should know, I used to be a potter, clay's nice and all...
but cracks really easilly in the face of freeze-thaw cycles and simple
mishandling.

If you really want it to last forever, make it out of indium. That stuff
just doesn't oxidise, better than gold in that regard. Also expensive,
very, very expensive... But, imagine SS tablets sputtered with a
protective indium coating.

--
peteSTOPspamspamspam_OUTpetertodd.ca http://www.petertodd.ca

2006\01\14@182705 by Marcel Duchamp

picon face
Peter Todd wrote:
>>I'll give you another hint.  The year was 1985.
>
>
> Oh! I know exactly why they are so earthshatteringly historic!
>
> I was born! :P
>

Whippersnapper!

2006\01\14@185634 by n Pergola (sent by Nabble.com)

flavicon
face



Olin Lathrop wrote:

===
...The year was 1985...
===

Hi Olin,

Thanks for the hint. Hmm, 1985, I was a junior in high school an all we had in school were IBM PCs and Apple IIs. I purchased my first computer, a Commodore 128, on August 19, 1985 (still have the antique). The C-128 did not have beautiful graphics like the ones you posted.

Tron came out in 1982 and that was pretty big at the time but 3 years earlier than 1985.

If you tell me that those images were produced by Adobe's Postscript language, I would be impressed (I believe Postscript was released in 1985).

The mid 1980s were big on pastels -- was that an early storyboard for Miami Vice? (Yes, that was supposed to be a joke).

Something to do with texture mapping? Z-buffer?


Ok, sorry, it's time to spill the beans:

Here's the ASCII in the TIFF files you posted:

Looking at long hallway from afar (TEMPLE). 2006 JAN 14 10:34:37  EST  Copied from file   D:\apollo\quest2.img
Looking down the long hallway (ARCADE). 2006 JAN 14 10:34:27  EST  Copied from file   D:\apollo\quest1.img

Are these clues?

1) Is the answer in your book?

2) Were the images produced by an Apollo workstation?

3) Quest1 and Quest2: Was 'Quest' a video game?

4) Was the graphics engine based on a Motorola 68xxx processor?

5) Is this related to IBM's release of the VGA standard? Not sure how close to 1985 that was.

Well, I'm out of guesses...tag you're it! :)

Best regards,

Ken Pergola

--
View this message in context: www.nabble.com/-OT-Is-your-oldest-CD-R-still-readable--t907869.html#a2384618
Sent from the MicroControllers - PIC forum at Nabble.com.

2006\01\14@195615 by olin piclist

face picon face
Ken Pergola (sent by Nabble.com) wrote:
> If you tell me that those images were produced by Adobe's Postscript
> language, I would be impressed

They weren't.

> Something to do with texture mapping? Z-buffer?

Not really either for those.

> Looking at long hallway from afar (TEMPLE). 2006 JAN 14 10:34:37  EST
> Copied from file   D:\apollo\quest2.img
> Looking down the long hallway (ARCADE). 2006 JAN 14 10:34:27  EST
> Copied from file   D:\apollo\quest1.img
>
> Are these clues?

Inadvertently, but probably only to those who already know the answer.

> 1) Is the answer in your book?

I don't think so.  I don't remember using one of the images in the book, but
then again that was a long time ago.

> 2) Were the images produced by an Apollo workstation?

Yes!

> 3) Quest1 and Quest2: Was 'Quest' a video game?

No.

> 4) Was the graphics engine based on a Motorola 68xxx processor?

These were all rendered in software.

> 5) Is this related to IBM's release of the VGA standard?

Not at all.

> Well, I'm out of guesses...tag you're it! :)

OK.  The images are two frames from the animated movie Apollo produced for
SIGGRAPH'85 called "A Long Ray's Journey into Light".  The significance is
that they were ray traced, which everyone at the time knew means it took
hours to render each frame.  This was the first time anyone had put together
a movie of more than a few seconds that was entirely ray traced.  Think
about the enormous compute power required.  It took several CPU hours to
render each frame, and you needed 24 of them just to make one second of
animation.  If I remember right, the movie was about 45 seconds long, which
was about half the time of the standing ovation it received from the
SIGGRAPH audience immediately after.  It may not seem like a big deal today,
but it was a very big deal back then.  Rendering a few ray traced frames was
tough enough, but over 1000 of them!!?

To put this in perspective, Al Barr got major applause at SIGGRAPH'82 when
he showed about a 10 second ray traced animation of an object rotating.  His
object was deliberately chosen to have symmetry, so he only had to render
1/4 of the frames and just repeated them 3 more times to show the object
rotating a full circle.  Still everyone was quite impressed, and it took him
many nights on a Prime 750 to render the images.  The Apollo movie was only
3 years later.

Apollo made this movie to point out the aggregate computing power of a large
network of "little" machines.  There were over 1000 machines on the Apollo
network at the time, and special software was written so that you could
allow your node to participate in the collective rendering when you weren't
using it, like at night.  Really only Apollo could have done this at the
time.  Nobody else had that kind of untapped computing power hanging around.
Others, like government labs, had substantial computing power, but it was
expensive and needed to be put to good use.


******************************************************************
Embed Inc, Littleton Massachusetts, (978) 742-9014.  #1 PIC
consultant in 2004 program year.  http://www.embedinc.com/products

2006\01\14@204020 by Peter Todd

picon face
On Sat, Jan 14, 2006 at 07:56:12PM -0500, Olin Lathrop wrote:
> Apollo made this movie to point out the aggregate computing power of a large
> network of "little" machines.  There were over 1000 machines on the Apollo
> network at the time, and special software was written so that you could
> allow your node to participate in the collective rendering when you weren't
> using it, like at night.  Really only Apollo could have done this at the
> time.  Nobody else had that kind of untapped computing power hanging around.
> Others, like government labs, had substantial computing power, but it was
> expensive and needed to be put to good use.

Wow, thanks for sharing that! Reminds me of my first computer, a
1983-built IBM XT my parents (reluctantly) bought for $50... Brings back
memories when everything was bloody difficult!

These days I'd have to write some software to run spare cycles on all
the 18F series PIC chips I have in verious projects, used only because
the extra cost is worth only a few hours of my time and they support C
easilly, running at 20mhz because I'm too lazy to stock anything but
20mhz crystals... Lots of spare cycles! Just no network connections...

--
spamBeGonepeteSTOPspamspamEraseMEpetertodd.ca http://www.petertodd.ca

2006\01\14@205405 by n Pergola (sent by Nabble.com)

flavicon
face




Olin Lathrop wrote:

===
...The images are two frames from the animated movie Apollo produced for
SIGGRAPH'85 called "A Long Ray's Journey into Light"...
===

Hello Olin,

Ok, thanks for the dénouement!

Interesting stuff. Now I know where 'quest' comes into play in all of this.

Quest: A Long Ray's Journey into Light

Too bad I'm unable to find a downloadable version of it -- I'd really like to see it. Hmm, going back to the subject of this thread, you could test out those Kodak Gold CD-Rs that you stored the hundreds of frames on, and string them together in an animated GIF or something along those lines. (Yes, I'm just kidding about this.) :)

Best regards,

Ken Pergola

--
View this message in context: www.nabble.com/-OT-Is-your-oldest-CD-R-still-readable--t907869.html#a2385555
Sent from the MicroControllers - PIC forum at Nabble.com.

2006\01\14@211012 by David VanHorn

picon face
> If you really want it to last forever, make it out of indium. That stuff
> just doesn't oxidise, better than gold in that regard. Also expensive,
> very, very expensive... But, imagine SS tablets sputtered with a
> protective indium coating.


There's a book on this subject, called "Deep Time"  A very good read.

2006\01\14@215632 by Dave Tweed

face
flavicon
face
olin_piclist@embedinc.com (Olin Lathrop) wrote:
> Ken Pergola (sent by Nabble.com) wrote:
> > 2) Were the images produced by an Apollo workstation?
>
> Yes!

108 of them, in fact.

> > 3) Quest1 and Quest2: Was 'Quest' a video game?
>
> No.
>
> > 4) Was the graphics engine based on a Motorola 68xxx processor?
>
> These were all rendered in software.

And yes, the workstations were all 68xxx-based.

{Quote hidden}

Close enough. I'll give you partial credit. I was working at Apollo at the
time, and my own desktop machine participated in the effort.

"Quest: A Long Ray's Journey Into Light" was actually the *second* such
movie produced by the network at Apollo. The first was called "Fair Play"
and was about 1:45 of actual ray-traced animation (the opening and closing
credits add to the length of the overall recording). "Quest" is actually
slightly over 2 minutes long, and the credits say that it was accomplished
in 7 weeks of elapsed time, using 52,000 hours of CPU time. In other words,
the 108 machines spent an average of about 10 hours each day on the
project.

> To put this in perspective, Al Barr got major applause at SIGGRAPH'82
> when he showed about a 10 second ray traced animation of an object
> rotating. His object was deliberately chosen to have symmetry, so he only
> had to render 1/4 of the frames and just repeated them 3 more times to
> show the object rotating a full circle.  Still everyone was quite
> impressed, and it took him many nights on a Prime 750 to render the
> images.  The Apollo movie was only 3 years later.

... and the animations of the myriad objects in the Apollo movie are all
out of sync to prove that no such shortcut was taken -- every frame was
fully and independently rendered.

> Apollo made this movie to point out the aggregate computing power of a
> large network of "little" machines.  There were over 1000 machines on the
> Apollo network at the time, and special software was written so that you
> could allow your node to participate in the collective rendering when you
> weren't using it, like at night.  Really only Apollo could have done this
> at the time.  Nobody else had that kind of untapped computing power
> hanging around. Others, like government labs, had substantial computing
> power, but it was expensive and needed to be put to good use.

It was done in the same manner as SETI@Home was done more recently -- work
was farmed out to idle machines by a master server during off hours.
Therefore, the group of engineers who conceived and managed this called
themselves "The Midnight Movie Group".

-- Dave Tweed

2006\01\14@221726 by andrew kelley

picon face
<about dist. processing on desktops>
Also done for cracking RC5 and finding OGR's and whatnot at http://www.distributed.net

--andrew

2006\01\14@221943 by Peter Todd

picon face
On Sat, Jan 14, 2006 at 09:10:12PM -0500, David VanHorn wrote:
> > If you really want it to last forever, make it out of indium. That stuff
> > just doesn't oxidise, better than gold in that regard. Also expensive,
> > very, very expensive... But, imagine SS tablets sputtered with a
> > protective indium coating.
>
>
> There's a book on this subject, called "Deep Time"  A very good read.

Thanks! I'll take a look at it sometime, the amazon listing for it looks
very interesting.

Similar to the Long Now Foundation come to think of it.

--
KILLspampetespamBeGonespampetertodd.ca http://www.petertodd.ca

2006\01\14@230142 by Peter Todd

picon face
On Sat, Jan 14, 2006 at 11:10:12PM +1300, Jinx wrote:
> > > "Flash/data EEPROM retention :  > 40 years"
> >
> > Doh! I must have looked at that a thousand times by now... Thanks!
> >
> > That said, do you know of any more indepth discussion of this?
>
> There are quite a few AN papers on EEPROMs eg,

Interesting links... But every single one talks about endurance
exclusively, not one mention of data retention. :(

--
EraseMEpetespamEraseMEpetertodd.ca http://www.petertodd.ca

2006\01\14@234207 by Jinx

face picon face

> Interesting links... But every single one talks about endurance
> exclusively, not one mention of data retention. :(

I did say "eg". If you look around MChip you'll find others

eg <<<----- !!!!!

TB072

http://ww1.microchip.com/downloads/en/AppNotes/91072a.pdf

and Go ogle on the web

eg <<<----- !!!!!

http://www.seas.upenn.edu/~ese570/1244.pdf

2006\01\15@060438 by William Chops Westfield

face picon face

On Jan 14, 2006, at 3:36 PM, Peter Todd wrote:

> If you really want it to last forever, make it out of indium.
> That stuff just doesn't oxidise, better than gold in that
> regard. Also expensive, very, very expensive...

I think you mean something else, perhaps iridium?  Indium is neat
stuff, but it's very soft, oxidize moderately easily (Indium Tin
Oxide is the transparent conductive electrode on most LCDs), and
only about as expensive as silver (call it $1/gram.)  I've got a
good quantity of indium from eBay that I've used to make room
temperature liquid metals (with gallium.)

BillW

2006\01\15@121050 by Gerhard Fiedler

picon face
William ChopsWestfield wrote:

> The other thing to realize is that actual user-created content
> that MUST be backed up tends to be pretty small.  My several
> years worth of little Eagle projects zips down to less than 20Mbyte,

I think it's good to be careful with zipping up files for backups. With
partially corrupted media (which doesn't seem to be that rare in restore
situations), zip files can cause a much greater loss than the actual media
loss caused. With the current prices of harddisks, I don't think there's
much of a need to zip anything for backup. Or if zipped, zip individual
files.

Gerhard

2006\01\15@123408 by Peter

picon face

On Sat, 14 Jan 2006, Peter Todd wrote:

{Quote hidden}

I don't think that stainless competes in the same league as fired clay,
or even glass. Gold is *very* permanent but it is often transformed into
something else as time passes (other objects), because of its intrinsic
value. Clay does not have that problem. Etching things into stone also
works. This can be done mechanically or with acid. There are very few
'permanent' options on a human scale. Pottery and fired clays (bricks,
tables, mosaic) are the only known 'media' that convey graphics and
writing over 5000 years and more. The other known media that survived
'well' are hewn stone and cave paintings ;-)

Peter

2006\01\15@135404 by Gerhard Fiedler

picon face
Mario Mendes Jr. wrote:

> Pen and paper, people!  Perfect example -> they just found the dead sea
> scrolls a short while ago and they can still read it after nearly 2000
> years

I don't know, but I'm pretty sure they were not made of paper -- at least
not of anything that resembles what we call "paper" :)

Gerhard

2006\01\15@140043 by Gerhard Fiedler

picon face
Ken Pergola (sent by Nabble.com) wrote:

> Some people will read that article and accept it as pure truth. To me,
> it's not about one media type versus another, or backup strategies
> (whole different topics), it's about specific claims made in the article
> about CD-R shelf-life/longevity that seemingly went unchecked, and was
> published anyway.

I'm not sure about the whole thing, and it seems nobody is -- including the
manufacturers. You possibly can take the amount of "data safety warranty"
you can get from them as a measure for how sure they are. How much can you
get? Not much more than the media is worth, I presume, and that's usually
less than a few dollars per CD. That's not an indication of a whole lot of
data safety on the side of the manufacturers.

Gerhard

2006\01\15@160431 by Peter Todd

picon face
On Sun, Jan 15, 2006 at 03:04:41AM -0800, William Chops Westfield wrote:
>
> On Jan 14, 2006, at 3:36 PM, Peter Todd wrote:
>
> > If you really want it to last forever, make it out of indium.
> > That stuff just doesn't oxidise, better than gold in that
> > regard. Also expensive, very, very expensive...
>
> I think you mean something else, perhaps iridium?  Indium is neat
> stuff, but it's very soft, oxidize moderately easily (Indium Tin
> Oxide is the transparent conductive electrode on most LCDs), and
> only about as expensive as silver (call it $1/gram.)  I've got a
> good quantity of indium from eBay that I've used to make room
> temperature liquid metals (with gallium.)

Yup, you're totally right, iridium it is.

By make room-temperature liquids you mean actually mass and mix the
constitute metals yourself?

--
@spam@pete@spam@spamspam_OUTpetertodd.ca http://www.petertodd.ca

2006\01\15@161327 by Peter Todd

picon face
On Sun, Jan 15, 2006 at 07:34:10PM +0200, Peter wrote:
> > If you really want it to last forever, make it out of indium. That stuff
> > just doesn't oxidise, better than gold in that regard. Also expensive,
> > very, very expensive... But, imagine SS tablets sputtered with a
> > protective indium coating.
>
> I don't think that stainless competes in the same league as fired clay,
> or even glass. Gold is *very* permanent but it is often transformed into
> something else as time passes (other objects), because of its intrinsic
> value. Clay does not have that problem. Etching things into stone also
> works. This can be done mechanically or with acid. There are very few
> 'permanent' options on a human scale. Pottery and fired clays (bricks,
> tables, mosaic) are the only known 'media' that convey graphics and
> writing over 5000 years and more. The other known media that survived
> 'well' are hewn stone and cave paintings ;-)

Well the value thing is a definete problem, I can totally see stainless
panels being mistaken for silver and stolen. That said, for mass storage
I see some *big* issues in trying to handle any reasonable quantity of
fired clay tablets. Heck, look at the common image of some archiologist
carefully peicing together litle clay shards from some site...

Just depends on your tradeoffs I think. If it were to store a few
"kilobytes" of info, I'd do it on clay. But more? Definetely some sort
of non-brittle material, just so I can make thin, compact, sheets of it.

As for it getting stolen... Store it in a cavern accessed by a very long
tunnel. Then line that tunnel with long-life radioactive isotopes
releasing gamma radiation. While long-life and intensity are mutually
incompatable, a long enough tunnel will fix that... Then the only people
who could get to the end of my tunnel and look at the artifacts without
getting killed are those with enough technology that stainless wouldn't
be very valuable to them!

--
spamBeGonepetespamKILLspampetertodd.ca http://www.petertodd.ca

2006\01\15@203156 by William Chops Westfield

face picon face

On Jan 15, 2006, at 1:18 PM, Peter Todd wrote:

> By make room-temperature liquids you mean actually mass
> and mix the constitute metals yourself?

Yes.  Both gallium and indium melt easily at stove-top temperatures,
and some of their alloys (perhaps with other components) stay liquid
down to room temp and below (I think the lowest has tiny and zinc and
is liquid down to 6 C.)  I apparently didn't do it all quite right,
cause one of my attempts came out more "pastey" than liquid, but it's
still neat to play with (not as much fun as mercury; the Gallium
indium allows tend to wet most surfaces rather than globing up.
But much less poisonous.)

BillW

2006\01\15@212518 by David VanHorn

picon face
Gallium gives me a headache for some reason, and it wets glass beautifully.
Indum "Squeals" when you bend it, interesting.
Beryllium is fun when you have an alpha emitter handy.

2006\01\16@015038 by n Pergola (sent by Nabble.com)

flavicon
face

Now, the good news...

All other things being equal (like proper care and storage), the consumer at least has a choice in the organic dye type and reflective layer material when they buy CD-Rs (dictated by the various choices the manufacturers currently offer).

>From the reading ("research") I've done, the manufacturers that are touting the very longest life of their CD-Rs typically use phthalocyanine as the dye chemistry (because it is more stable than azo, and azo is more stable than cyanine dyes), and gold (Au) for the reflective layer material due to its high marks in the 'resistance to oxidation' department. I read a Kodak study and their goal of long life for their Kodak PhotoCD Gold discs drove them to use these materials (phthalocyanine dye and gold reflective layer).

If your CD burner software does not tell you the dye chemistry type/manufacturer (type 0, 1, 2, 3, 4, 5, 6, 7, 8, 9) for your disc, there are utility programs out there that should be able to help you in this regard (probably less error-prone than the "eyeballing it" method of identifying dye type).

One web site I stumbled upon lists a handy chart which you can use as a "look-up table" to translate the type number to the actual dye chemistry and manufacturer:

http://www.cdmediaworld.com/hardware/cdrom/cd_dye.shtml

(I do not know how accurate that information is, but finding a "second source" to verify the information presented in the table would be useful.)

Staying on topic of CD-R media only, from what I've read, I personally would feel a bit uneasy if I had some older discs that used cyanine dye. If the data was really important, I personally would copy the CD-R over to a CD-R that used azo or phthalocyanine dye (with my preference being phthalocyanine). But everyone has to make their own decisions in a case like this.

And for very serious stuff that I did not want to waste my time periodically checking in the future, I personally would use a CD-R that is recommended by the manufacturer specifically for long-term archival purposes. The "cream of the crop" appears to be a combination of phthalocyanine as the organic dye chemistry and gold as the reflective layer material. Obviously this combination appears to be the most expensive, but it might not be as expensive as you might think (expensive is a subjective term).

Again, just focusing on CD-R media (other storage media and backup strategies aside) there are choices out there for the consumer to make. If this is important to you, please do your research and make your own decisions based on what you've learned. There are a lot of white papers and scientific test results out there to wade through. There is also a lot of science and engineering behind this technology -- as always, the devil's in the details. But you have a choice as a consumer and that is a good thing!

Best regards,

Ken Pergola

P.S. I'm definitely no expert on this subject and my experiences are anecdotal, but I think I've learned more about CD-Rs (more than I probably wanted to know) after that article came out that prompted me to start this thread.

--
View this message in context: www.nabble.com/-OT-Is-your-oldest-CD-R-still-readable--t907869.html#a2399610
Sent from the MicroControllers - PIC forum at Nabble.com.

2006\01\16@071451 by olin piclist

face picon face
Dave Tweed wrote:
> Close enough. I'll give you partial credit. I was working at Apollo at
> the time, and my own desktop machine participated in the effort.
>
> "Quest: A Long Ray's Journey Into Light" was actually the *second* such
> movie produced by the network at Apollo. The first was called "Fair
> Play" and was about 1:45 of actual ray-traced animation (the opening
> and closing credits add to the length of the overall recording).
> "Quest" is actually slightly over 2 minutes long, and the credits say
> that it was accomplished in 7 weeks of elapsed time, using 52,000 hours
> of CPU time. In other words, the 108 machines spent an average of about
> 10 hours each day on the project.

I'm sorry Dave, but you're confusing Quest and Fair Play.  Quest was
definitely first, and was produced before I joined Apollo.  Fair Play was
being planned when I joined Apollo in 1986, and I helped a little and my
workstation also contributed to the rendering.  If you can somehow get hold
of a copy or Fair Play, you will see my name on the credits.  I think I was
called "Waiter #1" or something like that as a joke.  I mainly kept the
finnicky Dunn camera properly adjusted, and I also contributed a little to
the rendering software.

The original recording of the Fair Play pictures was on 16mm movie film, not
video as many believe.  The Dunn camera was a device for recording computer
images onto film.  It had a black and white CRT with with camera pointed at
it and a rotation filter wheel in between.  The computer would display the
red image channel, the red filter would be rotated into place, the film
exposed, then the same for the green and blue channels.  This process took
several seconds per frame.

Bonus challenge: Why wasn't a color CRT used without a filter wheel?


******************************************************************
Embed Inc, Littleton Massachusetts, (978) 742-9014.  #1 PIC
consultant in 2004 program year.  http://www.embedinc.com/products

2006\01\16@142033 by Chetan Bhargava

picon face
My oldest CD-R is 8.5 years old. The CD-R is HP brand and still reads.
It was recorded by HP-Surestore CD-Drive. :-)

On 1/12/06, Ken Pergola (sent by Nabble.com) <.....listsspam_OUTspamnabble.com> wrote:
>
> How old is your oldest recorded CD-R disc?
>
> Is it still readable?

--
Chetan Bhargava
Web: http://www.bhargavaz.net
Blog: http://microz.blogspot.com

2006\01\16@160724 by Dave Lag

picon face
Olin Lathrop wrote:
{Quote hidden}

.....
from another old fart:

Hello Dave

       Actually, I knew all this, and I recognized the images
immediately (too bad no money was being offered). The apollo
sales guys showed us the 10min animated clip about 25 years
ago when we bought our first apollo. In fact, I may still have
that video clip kicking around someplace, although I'm not
sure if it will run on anything today. What was really funny
were the credits at the end, -things like "Megabit Master- john
smith" etc.

                                      Wayne
....

2006\01\16@170628 by Peter

picon face

On Sun, 15 Jan 2006, Gerhard Fiedler wrote:

> Mario Mendes Jr. wrote:
>
>> Pen and paper, people!  Perfect example -> they just found the dead sea
>> scrolls a short while ago and they can still read it after nearly 2000
>> years
>
> I don't know, but I'm pretty sure they were not made of paper -- at least
> not of anything that resembles what we call "paper" :)

Papyrus and sheepskin prepared in a special way were the most used
materials afaik.

Peter

2006\01\17@010635 by Russell McMahon

face
flavicon
face
> And for very serious stuff that I did not want to waste my time
> periodically checking in the future, I personally would use a CD-R
> that is recommended by the manufacturer specifically for long-term
> archival purposes. The "cream of the crop" appears to be a
> combination of phthalocyanine as the organic dye chemistry and gold
> as the reflective layer material. Obviously this combination appears
> to be the most expensive, but it might not be as expensive as you
> might think (expensive is a subjective term).
/>

Which technology is "found" to work best depends, alas,  on who writes
the reports, and who patented what relative to the marketing
arrangements of a given organisation. Cyanine, Phthalocyanine and Azo
dyes are all patented and willingness to pay others royalties seems to
influence technical choices. Wikipedia has a who patented what
summary. I have seen reports from people using Cyanine dyes that claim
archival times of around a century. And other reports that say 'tis
not so.

While buying the best from a reputable manufacturer with a superb
track record may ease the effort in making sure the data of today is
as accessible in 100 years as the data from 1906 is today, you CANNOT
just replace period checking with blind (or even informed) faith.

MUCH of the records/photos/personal recordings of the last decade or
two and possibly of the next decade or two will be lost to history.

*YOUR* family photos, records etc are on average less safe on
electronically readable media than on well designed and operated paper
based systems. An informed and diligent user can expect to perform
well above average, but many will lose their irreplaceable records.

___________

An August 1998 backup CDR, Sony 650 MB, CDQ-74BN, "For professional
use", reads OK on a 52X CD drive but fails to get "drive ready" ona
dual layer DVD writer.

A May 2000 Verbatim CD containing Outlook Express email files from
1998-1999 opened in BOTH drives and the data seemed intact BUT I was
unable to open any of the email folders either directly or by
importing from OE6. An XP web search for a suitable program for MBX
files suggested Eudora or, surprise surprise, Outlook. Whether this
would work I don't know as i don't have it installed on anything here
and am not inclined to let it trash anything else when let loose as it
has done before now (likes to be the boss).

So: One drive reads one disc, one reads both. ButI can't utilise the
data on one due to format creep.I wonder if anything will read Jpg 50
years from now ? :-).


       RM




2006\01\17@055925 by Howard Winter

face
flavicon
picon face
Russell,

On Tue, 17 Jan 2006 19:05:10 +1300, Russell McMahon wrote:

> An August 1998 backup CDR, Sony 650 MB, CDQ-74BN, "For professional
> use", reads OK on a 52X CD drive but fails to get "drive ready" ona
> dual layer DVD writer.

FWIW I've always found that DVD drives are much less able to read dodgy CDs than CD-only drives, even back
when they were readers only.  Having multiple capabilities obviously involves some compromises, and it looks
like reading marginal CDs was one of those...

Cheers,


Howard Winter
St.Albans, England


2006\01\17@060700 by Gerhard Fiedler

picon face
Russell McMahon wrote:

> So: One drive reads one disc, one reads both.

Yes, besides the media itself, the reading methods change. Probably a good
idea to keep your older drives around for a while, and to check your older
media with your newer drives.

> ButI can't utilise the data on one due to format creep.

Also probably a good idea is to create an at least mental list of the
formats you use for long-term backups and follow their development. Avoid
proprietary formats that require readers that are not available as separate
installs, if possible on multiple platforms. Or make sure that you
regularly "refresh" the format of proprietary data by loading it in the
appropriate application, transform it into the always latest version and
re-archive.

I'm a fan of harddisk storage. I don't see anything as convenient in that
price range. Even considering the potential mechanical problems... can be
solved by duplicating the data every 5 years or so on a second, new drive.
All the re-formatting that will be necessary over time (if you think in
decades) can relatively easily be done on harddisks (at least when compared
to any -/+R/W media).

> I wonder if anything will read Jpg 50 years from now ? :-).

You'll know quite some time before no readers will be available anymore
that the format will be dying. Image batch converters can take care of
that... Just don't think that data or formats last forever.

Gerhard

2006\01\17@155235 by Mike Singer

picon face
Howard Winter  wrote:
> FWIW I've always found that DVD drives are much
> less able to read dodgy CDs than CD-only drives,
> even back when they were readers only.


Old CD-only drives' lasers was not adaptive power.
They read R/W disk awully, DVD drives do the job well.
But I found that my new LG DVD can't burn some old many times burned
no-name CDRWs, those that old LG CDRW drive burns OK.
And it seems that with new brand CDRW disks my LG DVD burner is better
than my old LG CDRW. (I have both burners installed on my PC)

Mike.

2006\01\18@124117 by digitaladdictions

picon face
I have never had problems with memorex cd's but I will never again use
there DVDs and have had such bad experiences with them I will not
purchase anything from the company anymore.  I burn alot of DVDs
personal backup and at work we use VPCs for demos. Back when DVDs
still cost ~$2 each I had two Memorex 4x 50pk spindles they were
purchased to be used in a DVD Recorder to convert VHS to DVD. The
recorder was a Christmas gift and thus the time between purchasing the
DVDs and them being opened and used was to long to return them.  Both
spindles were completely bad and could not burn on the recorder or my
dvd burner in my computer.

A few months later I bit the bullet and bought a 50pkg of 8x Memorex
from Best Buy because they were half price.  None of them burned
faster than 4x and some slower.  Meanwhile a friend at work was having
troubles burning some "backups" of his movies and I was trying to help
troubleshoot and it ended up that he had a bad spindle of memorex
dvds.

Without starting to sound repetitive in the end I have had 4 50pk's of
memorex purchased at different times from different locations all be
completely bad. Me and numerous of my friends also had problems with
there 8x not burning at 8x.

Perhaps they entered the DVD media market prematurely before there
process was properly tested and refined but in either case I will
never buy from them again.

I have had very good experience with Sony DVD-R's and Verbatim CD-R's.

Only media I ever had go bad on me after being properly burnt was
Legacy brand DVDs that were a quarter of the normal price and dye's
aside you could tell were just physically bad disks.  I have been
burning CDs for probably 7 years now but don't tend to keep the disks
nearly that long.

</rant>

~justin

More... (looser matching)
- Last day of these posts
- In 2006 , 2007 only
- Today
- New search...