# CD/DVD life span



## firebird (May 31, 2010)

Hi

I just caught part of TV programme the other day that said some CD's and DVD's start to deteriorate after 3 or 4 years. They recommended that new copies were made on a regular basis. Can you imagine getting out a 20 year old CD of family photo's only to find it is useless. I have hundreds of CD's full of photo's and data that I assumed were a good hard copy but it appears I was wrong. What a mammoth job its going to be (not to mention the expense) to make new copies of them all. Has any body suffered this problem??

Cheers

Rich


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## Tin Falcon (May 31, 2010)

Firebird: I would not panic yet read here http://www.clir.org/pubs/reports/pub121/sec4.html some studies suggests the shelf life of some disk can be more like 30 years. Worth some research.
Tin


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## Blogwitch (May 31, 2010)

Rich,

I am getting the odd failure on discs that are only about 2 years old. Luckily, I have been able to rescue most of the contained data.

I think commercial CD's and DVD's are pressed like the old style records, but the ones we use to burn with are actually made with a very thin foil between two discs of plastic. It seems that the foil is liable to oxidation because of when the parts are joined together, the seal is not perfectly air tight. You can somtimes see the areas that are affected.

John


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## mklotz (May 31, 2010)

A more pertinent question might be...

What's the probability that CD and DVD drives will still exist twenty years from now?

My guess is that the computer of the future will be purely electronic. The only mechanical thing in it will be the power supply fan and even that might be some sort of electrostatic air mover 'thing'.


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## Troutsqueezer (May 31, 2010)

I've been in charge of the family history media for the last twenty years. Through the years I've read all kinds of estimates as to life spans. I make backups from time-to-time of the movies and photos just to be on the safe side. That said, I've kept the original CD's and DVD's and they still work fine, going on close to 15 years for some CD's. about 10 years for DVD's and still tickin'. 

For fans and power supplies, the future will no doubt bring inductive power to the home scene. You pull only as much power as needed from the wall but with no wires, just lines of flux. There are working prototypes now. My wife will be happy, she hates electrical wires. 

-Trout


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## cidrontmg (May 31, 2010)

From mklotz:
"What's the probability that CD and DVD drives will still exist twenty years from now?"

I´d also think it´s very near zero, museum exhibits excluded. Same goes for hard drives, they´re right now being substituted with SSD´s (Solid State Disks/Drives) in new laptops, and within 2-3 years in desktops as well. I wouldn´t buy Seagate, Western Digital, etc. stock now... SSD´s are still quite costly/Gb, but they´re already available with 0.5 Tb - that takes an awful lot of CD´s, or even DVDs to fill.
CDs/DVDs will go the way of floppy disks, analog modems, CRT displays, cassette tapes and Centronic printer ports. Far sooner than most people think.
Not sure about the fans, though. There´s usually at least 3 fans now in a desktop, PS, CPU and video GPU. They seem to get heftier with each generation, and the alternatives (Peltier elements, water cooling, heat pipes, etc.) have had only a moderate success, and usually still have at least as many fans in them as they were supposed to replace.


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## shred (May 31, 2010)

Note that SSD's and flash drives also have a relatively short lifespan before the charge in the flash cell degrades too much to be readable. Don't expect data you put on a USB flash drive or memory card to be there ten years from now if you just leave it on a shelf (nb: the same goes for hard-drives; leaving them on a shelf is in general a bad idea for long periods of time. It's why tape is still with us).

Twenty years from now you'll be able to find a reader here and there stuffed in closets. The 5-1/4" floppy went obsolete in the early 90's and if you look, drives can be found for them. I've got a complete Apple II from 1978 and a circa 1986 Amiga stashed that still work (ok, maybe it could be called a 'museum' ). CDs and DVDs are much more prevalent than those ever were, so I'd put good odds you'll be able to read them if you want. You'll probably have to go to some effort to do so, and it'll be even odds if the disk is readable, but there you go.

Now 8" floppies, hard-sectored 5-1/4's and large-format tapes on the other hand... there's businesses that make good money reading those when the need arises.

"small" SSD's and "small" hard drive cost-curves are approaching parity, but a "small" SSD is 8 or 16GB while a "small" HD is 20 times bigger. It'll be a while yet before rotating rust gives way completely.


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## doubletop (Jun 1, 2010)

Shred

Do you wear any form of protective clothing when you use the Apple?

In those in those days PSU's had huge capacitors . I have an Ohio Superboard clone kit with 70,000uf capacitors in the PSU. I'd need to take it out to the back blocks if I wanted to switch it on now. Backup of my serious stuff on the Superboard was done on punched tape on an old ASR33 teletype as the CUTS tape interface was hopeless. The ASR33 is long gone.

In the early 80's I designed and built a Z80 based CPM system from the ground up. It had 8" drives, then 5.25" drives and then I moved into the big time with a 10Mb hard disk. I managed to get all the 8" disks onto that one drive. Again a big static PSU (although I do have an early switched mode PSU for it). Same problem big electrolytic capacitors and a potential for a big bang if switched on.

Those were the days.......

I think the point is in 20 years time you'll be able to get all that mass of stuff you have today on your 1Tb drives onto something we can only dream of now. So it will be cheap to have multiple copies distributed wherever you want, just keep buying the technology and transcribe from one storage system to the next.


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## firebird (Jun 1, 2010)

Hi

Comforting words of wisdom, I like it. Just to set my mind at rest I dug out some CD's that are about 12 years old. They have been stored in one of those zip folders with 100 compartments. No problem, they all read ok. ;D ;D ;D
5 or 6 of them do appear to be slightly discoloured though, I'll make back ups of those.

Cheers

Rich


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## cidrontmg (Jun 1, 2010)

Shred:
"Now 8" floppies, hard-sectored 5-1/4's and large-format tapes on the other hand... there's businesses that make good money reading those when the need arises."

Exactly. I´d bet you can´t just slam a CD/DVD/BluRay to a slot in your machine 20 years from now, and expect a file selector box to show up. There won´t be a slot, just as there´s no slot for 8", 5 1/4" or even 3 1/2" floppies in today´s machines. And if you hook up a CD/DVD reader to the machine, there certainly won´t be drivers for the reader (unless you write one yourself), for whatever operating system the machine uses (Windows 15, 256-bit???). You just can´t read it any more, unless, of course, you´re willing to do what you did with your Apple II and Amiga - preserve a machine from 2010 for the next 20 years. Reading CD/DVD media just won´t be possible with your home machine 20 years from now, it´s something specialized businesses do for a top dollar.


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## Chazz (Jun 1, 2010)

The only thing I can add is keep the media (Cd's, DVD's) out of sunlight, other than that, scratch free and away from radical temperature changes and they should outlast the machine technology.

I work in IT and we have Client backups on CD going back to the early 90's that read just fine.

Cheers,
Chazz


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## Noitoen (Jun 1, 2010)

From what I hear, the problem with the CD/DVD's loosing data with age, mainly occurs on the rewritable types. They use some kind of organic compound that deteriorates in time.


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## shred (Jun 2, 2010)

cidrontmg  said:
			
		

> Shred:
> "Now 8" floppies, hard-sectored 5-1/4's and large-format tapes on the other hand... there's businesses that make good money reading those when the need arises."
> 
> Exactly. I´d bet you can´t just slam a CD/DVD/BluRay to a slot in your machine 20 years from now, and expect a file selector box to show up. There won´t be a slot, just as there´s no slot for 8", 5 1/4" or even 3 1/2" floppies in today´s machines. And if you hook up a CD/DVD reader to the machine, there certainly won´t be drivers for the reader (unless you write one yourself), for whatever operating system the machine uses (Windows 15, 256-bit???). You just can´t read it any more, unless, of course, you´re willing to do what you did with your Apple II and Amiga - preserve a machine from 2010 for the next 20 years. Reading CD/DVD media just won´t be possible with your home machine 20 years from now, it´s something specialized businesses do for a top dollar.


It takes a looong time for a legacy format like CD to go away completely. PC rate of improvement has leveled off a lot, so 10 and 15-year old machines are still around, especially in industrial and fixed-function places. Windows XP embedded doesn't even go off official support until 2016.  New HAAS mills come with 3-1/2" floppy drives today. 20 years from now somebody on your block will be able to load a CD into a machine they own that works.

As for the Apple PSU, the Apple II had one of the first switching power supplies, so no honking caps, or at least less of them.


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## doubletop (Jun 5, 2010)

Shred you are right. I'd imagine that commercially produced computer like the Apple II would be a bit more robust that something homemade, and if its been switched on irregularly over the past 32 years it is more likely to work.

I soldered every joint in both my antiques and some of the components came out of the junk box. One day, when I've washed my Kevlar underwear, I may just power them up and see what happens. If I'm really keen I may even make some attempts at reforming the capacitors.

http://www.vcomp.co.uk/tech_tips/reform_caps/reform_caps.htm

Pete


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## shred (Jun 5, 2010)

doubletop  said:
			
		

> Shred you are right. I'd imagine that commercially produced computer like the Apple II would be a bit more robust that something homemade, and if its been switched on irregularly over the past 32 years it is more likely to work.
> 
> I soldered every joint in both my antiques and some of the components came out of the junk box. One day, when I've washed my Kevlar underwear, I may just power them up and see what happens. If I'm really keen I may even make some attempts at reforming the capacitors.
> 
> ...


Replacing caps is pretty much de-rigeur on old electronics, especially monitors. Buried in this heap of papers I call an office is an original 1980 Missile Command arcade game (the cocktail table format, not stand-up). First thing I had to do was replace all the electrolytic caps in the monitor-- they even make kits for the common monitors.

FWIW, I saw the other day that the VHS tape turned 33 years old. Hollywood hasn't produced movies in VHS since 2006. There are said to be 94 million players in US households and you can still buy players and blank tapes...


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