I have cd at speed 8 Had a life of 5 years as I had mp3 on them an they went south in the year 2000.Wayne
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Last fall I took a class on photos and our instructor said that you should always store them on edge and any time you made a change in the system to make a new master and throw the older one away. He suggested replacing them every five years. Its a small thing to do and not worry about losing anything.
Your belief that CDs can last as long as LPs is, unfortunately, totally incorrect. Ever notice what happens to metal objects ? Over time they corrode or rust (i.e., oxidize ). This is a chemical reaction which is unavoidable, except if your CD is glass or gold (which does not oxidize). Most CDs are comprised of a thin aluminum layer on a thick plastic base. The aluminum oxidizes.
Yes, LPs will not have this problem. But ... CDs will *definitely* go bad -- just a matter of time and how much exposure to heat, water, air, and other substances which can accelerate oxidation. For example, CDs will go bad faster in the tropics than in Canada. (10-15 years)
I have personally had information begin to evaporate from CD's in less than 5 years. This has happened with more than one CD, but with several CD's that were 4 or 5 years old. I do also have some that are more than 8 years old that still have information intact. It is my understanding that if CD's (I assume this also applies to DVD's, but I have not had personal experience with DVD's.) are stored in an ideal environment (dark, dry, cool but not cold, etc) they will have a life much longer than some of mine which were exposed to sunlight, cold and hot conditions, and other conditions that portable media is subjected to. When I burn a CD or DVD, I date it with the month and year and I make a new copy and discard the old one every 3 years or so.
I really do not fully understand how what I am going to say here works, but it is my understanding that commercially produced CD's and DVD's are created by a different process than computer generated CD's and DVD's and have a much, much longer shelf life than computer generated media. I understand, however that even these cannot be expected to be readable when 30 or 50 years old.
That's my story, and I'm stickin' to it!
Like the other guy stated, the commercial cd and dvd's are pressed like a vinyl record so it is physically pushed into the material to create the pits and vallies that the laser reads as 1's and 0's.
A cd-r or DVD-R is made using a laser to etch the spots into the material and the problem is oxygen gets to this material and eats away at it over time, oxydation, like rust destroys the data so the disc can no longer be read reliablly. The name for this is disc rot, and it is documented, try googling it.
I wonder if storing your important cd or dvd's in an air tight plastic container or say a vacumm sealed bag would help?
It theoretically should keep the oxygen out, right?
Thank you, AnthonyNYC. Now, I know why I have not had a single, not ONE, pressed commercial CD fail on me in the 26 years I have had CD's! However, many burned CD's and DVD's have failed quite frequently. Nowadays, I use Fuji (probably one of the top brands) to back up, create at least 3 copies of each for redundancy, and keep a final backup on hard drives. Works for me!
Sealing them in a plastic bag will not keep oxygen out. Oxygen permeates plastic and rubber. It will go through a plastic bag the same as it penetrates the plastic substrate of the CD. This is the same reason many people use nitrogen to fill their car tires. As the oxygen escapes through the rubber, the tire looses it's inflation. Nitrogen does not permeate rubber, so the tire keeps it's pressure longer.
I have not had a problem with CD's loosing their data, but MANY of my DVD's that are about 5-10 years old are now completely dead.
Though some last longer than others, they will become unreadable to Windows. Especially RWs which you have erased and rewritten and added to a number of times.
There is software to read these CDs and DVDs when Windows will not, and you can usually rescue the material on the discs.
I recommend Isobuster (free for this purpose), which has been able to recover most of and usually all the material by going over and over the material in damaged sectors.
(I first learned of this from someone in Support at Nero, though the company now has its own disk rescue product, which I haven't tested.)
Also useful for damaged audio CDs is EAC (Exact Audio Copier; also free):
It's also good for undamaged audio, but more time consuming than CDex.
I'd advise making certain your material is readable every year or two, and consider using a dedicated external hard drive as an alternate backup.
This subject has been dealt with at length previously, in fact I wrote a response to a similar question in 2006 that "won" that weeks response award (it was the 1/27/2006 column, if you want to look it up).
In a nutshell: You are PROBABLY being paranoid.
The best information available (and it's definitely somewhat limited since CD-R has only existed now for 14 years or so) is that QUALITY optical media burned on a quality PROPERLY WORKING drive, will last at least 50 years and some estimates go out to 300 years, based on the best avaialble lab work and analysis (it goes without saying that no one has been able to test even 50 years in real world conditions).
Now, however, a bunch of caveats:
1. Media: There is good media and there is junk media. And there are dozens of different dye formulations in at least five major dye families (if you care, they are Cyanine, PhthaloCyanine, Metallized Azo, Advanced PhthaloCyanine and Formazan). These all have significantly different characteristics (they WILL have different lifes), and each of them can be made into a "quality" or a "junk" media of that type. I guess it goes without saying that junk media, of any type, is just that .... junk.
2. Drives: There are good drives, there are bad drives and there are good drives that have become defective. It is my personal opinion that a lot of the problems that we have are caused by drives whose laser output power levels are below spec. That can happen even to a high quality drive that was once good (it can also happen simply because the optics have become dirty). So the media isn't heated to the proper temperature, the dye doesn't fully change it's reflectivity and you get a burn that consequently has poor long term stability. So the moral of this story is that everyone who has an optical burner should have a laser power meter and use it regularly (just kidding .....).
3. Storage and handling: This, too, effects life. Temperature, humidity, handling, storage type (it's better to store discs vertically; DVDs should not be flexed (including as in removing them from a case), scratches can do obvious damage, etc. etc.
So you put all of those factors together and they all impact the life of your media. The estimates of 50 to 300 years were for quality media properly burned and properly stored. There is no absolute guarantee that any of us real world users will meet any of those critera much less all 3.
So what is the bottom line? Here is my conclusion:
All indications are that properly burned optical media will last for decades.
However, as all kinds of backups do fail, I ***ALWAYS*** have multiple backups. And I think that is one rule that applies for all backups of all types. One backup, even two, is NOT enough.
***NEVER*** use "RW" media (CD or DVD) of any type for anything that you plan to keep. Only use "R" media. Sorry, RW media just is NOT stable, I've had too many bad experiences with it in my 40+ years in the computer industry (only 10+ dealing with optical media, but that's enough for me .... I've seen a years long clear pattern emerge).
After using a drive for a while, and after using media that it has burned in other computers with other drives, you will get a sense of whether or not the drive is reliable. Pay attention to that; signs of unreliable operation (especially problems reading discs later, either in the same drive or other drives) should not be ignored. FWIW, I've had the best luck with Samsung (now TSST) and Pioneer and, frankly, much worse luck with almost all other drive brands (and I build and service computers, and this is based on hundreds of drives that I've dealt with).
Also, you mentioned "shelf life" in your query, that really would refer to the time BEFORE the media was burned, the time between when you bought the media (really, when it was made) and when you burned it (the time subsequent to burning would be the "archival life"). Shelf life is limited, optical media should be used with 5 years of it's date of manufacture, although in general we have no way of knowing when the media was made, but usually it will have been bought within a few months of manufacture.
Hope that this helps,
I do not explicitly dispute anything that Watzman has said here......BUT!!! Are you ready to bet your grandchildren's baby pictures that you have used "top quality" media (how can you distinguish top quality from mediocre?) and that you have a "top quality" CD drive and it is functioning perfectly? I certainly don't want to burn all my grandchildren's baby pictures to a CD and file them away in a box on a closet shelf expecting to pull the CD's out to embarrass the grandchildren with when they come home from college 20 years from now. (MUCH LESS 50 to 300 years)
I cannot vouch for "quality" of media or "quality" or condition of CD drive, but I have had pictures, saved documents, and data(OS back ups) disappear from CD's in LESS that 5 years!!!!!
Buying brand name media may increase your odds of getting higher quality blank media but it does not guarantee it. I have had plenty of name brand CD's go bad, especially from Memorex. And as far as Drives go, there is no way to know if your drive is a high quality drive or not. Unfortunately, there are just too many variables to rely on any single form of backup. Personally, Flash drives are about the least reliable method. All it takes is to remove it from your computer at the wrong time and poof, your data is gone. I use flash drives every day to bring my computer tools to clients and I now have a drawer full of defects that I have accumulated over the past few years. Here again, it depends on the quality of the drive but there is no way to know which are high quality and which ones are junk. The only answer for data that is really important to you is to keep multiple backups on different forms of media and to test it.
Re: "I have had plenty of name brand CD's go bad, especially from Memorex."
Memorex is NOT a "quality brand".
It's tough, because the "brand" is often not the manufacturer, and most "Brands" are selling discs supplied by multiple manufacturers. But Memorex is a brand that I actually avoid. Verbatim is a brand that is generally well regarded, although much if not all of their media is made for them by other firms. Taio Yuden is usually recognized as one of the higher quality manufacturers (they do supply Verbatim, among others), but they are a manufacturer and not a brand.
By the way, one comment that I should have included in my original post but forgot ... limit your burning speeds to about 32x or a bit slower (but not absurdly slow) for CD and 8x or less for DVD (and, of course, always the slower of the rated speeds for the drive and media). Extremely high speeds accentuate whatever problems the drive and/or media may have.
Flash drives are NOT a backup device, they are a transport device (like RW optical media, which I generally hate).
> "Buy name-brand CDs and DVDs. Those'll be top quality or close enough. Don't buy cheap. You get what you spend for."
Pfffft! Unfortunately, brand name don't really mean squat nowadays, too many "brand names" sell lower quality crap these days, and if anyone wants to insist you get what you pay for, I'm certain you will get a flood of replies from others who can give you specific examples of their expensive purchases that turned out to be rubbish even though they were paying more for supposed better quality.
Often difficult to know these days... any purchase I'm to make where I want to make absolutely certain I'm buying the best, I do many, many, many searches and read many reviews/ratings etc and customer opinions from many a different site (to try and defeat biased or faked ratings). This usually works.
I totally agree with you! "TOP QUALITY" is very relative term. You can't just determine this by price. The same brand can use different dye process depending on where they manufactured that batch. The price stays constant, but the quality might not.
Burning is also very delicate process. Slight bumps and vibrations can offset DVD or CD in the drive and cause an error. It might not manifest itself right away due to error correction, but with a bit of time it will show up more and more.
Re: "I cannot vouch for "quality" of media or "quality" or condition of CD drive, but I have had pictures, saved documents, and data(OS back ups) disappear from CD's in LESS that 5 years!!!!!"
You have a problem. Seriously, you do. I don't know if it's your media, your drive or something you are doing (again, DO NOT USE RW MEDIA FOR ***ANYTHING*** YOU WANT TO SAVE), but something is wrong. I am in the computer industry, I was a beta tester for Adaptec right after they bought "Easy CD" from Corel thru when they spun off their software division as "Roxio", and I have been using CD-R since 1994, thousands of discs (perhaps over 10,000). And the number I have burned that have later turned out to be bad for no explainable reason is in the low double digits (out of, again, thousands). And I am coming up on 15 "real" years now, I have 1994 to 1996 CDs and they are still just fine. Not some of them, but pretty much ALL of them (there are some I've never gone back to, but the point is that when I do go back ... and I do ... THEY WORK.
Had a nice time reading your reply. Sounded pretty positive. You could have posted the 2006 link as well to make it easier for the rest of us.
Personally though, I have had a problem with optical media older than 3 yrs old. Mold or something like that seems to grow on the surface making stuff unreadable.
Most of us have read the articles on this and CD-R and DVD+-R are rated as 5 years. I think you are confusing home burnt media with pressed media that you buy in a store. The articles I read say 5 years and many of us don't get even that much. At home, you are only hitting the disk with laser so that you are making dark spots on INK. Not on metal.
I am not confusing anything. Believe me, I understand the difference between pressed media and recordable media. And all of the manufacturers say that recordable media is currently believe to have a life of decades to centuries if it is properly burned, handled and stored. Take a look at my experience (listed above in a more recent post), I am a degreed engineer in the computer industry, at times working with optical media software and drive manufacturers. I am not your typical home computer user.
From a discussion on the OSTA (Optical Storage Technology Association) web site:
"manufacturers have claimed life-spans ranging from 50 to 200 years for CD-R discs"
That doesn't make it so, and since the technology has only existed for less than 2 decades, no one can "prove" anything. But it is an absolute fact that if you ask most manufacturers' engineers what they believe, off the record, most of them will tell you 50 to (200 or 300) years, for quality media, properly burned, and properly stored and handled. [Most of them will NOT say this publicly because of liability concerns; and most consumers may be unable to achieve "quality media, properly burned and properly stored and handled"; indeed, have no way of even knowing the quality of either their drives or media at all.].
[The OSTA page I quoted from is at http://www.osta.org/technology/cdqa13.htm]
I'm by no means an expert just a casual guy...but I will share my experiences with CDs. I was in high school in the late 90s (now over a decade ago) and got my first CD burner, burning at something like 8X!! Lol.
Anyway, the CDs I burned back then on Memorex and TDK, etc had been lying around with no cases, just in a big pile in my grandfather's garage for around 10 years, until a few months ago. I live in Alabama, very humid and this is not an air conditioned garage. I went through the box of a hundred or so CDs a while back and damn near 90% of them were good. Yes, after 10 years of lying in humidity and heat...the old burned CDs played fine. I ripped them all onto my itunes, of course.
I think some people tend to worry too much about this sort of thing. When you think about it, old video games from the 70's are working fine and the carts are holding the data over 30 years later. This was well before the technology had been refined. It's more uncommon to find an old Atari 2600 that DOESN'T work than to find one in good playing condition. What about the old Nintendo games? They still work and millions still play them daily...they've held up.
I own a Sega CD game console. These were made in the earl 90s, 1991 or 1992 and my factory made CD games from almost 20 years ago still look and play great. No rot. And it's not just me, plenty of people's CDs do.
I think it's like anything else...take good care of them and use common sense and CDs will last you.
Isn't it ironic that with all our wonderful modern technology we are struggling to make our recordings last? Compared with the Ancient Egyptians, Romans, and even Charlie Chaplin, we are in trouble, and they wrote things down in STONE, and used 'low-tech' stuff such as movie film. It's a good job that they did, and we can still 'listen' to them, and see them thousands and hundreds of years later. We will be lucky to leave anything to posterity, and it's all because of our greed for money and a quick buck! We are talking about preserving visual and audible records of ourselves, and yet we'll be lucky to even have a machine to play them on, in the not too distant future. Who knows? We may not even be using electricity in 100 years' time. When the hardware breaks down, or is no longer available, that's the end of it! All we can do is transfer our records to the latest medium as current media become obsolete.
50 to 300 years !! no way, Jose. ONLY IF THEY ARE GLASS OR GOLD would you stand a chance of going past 20 years, and only then if they were hermetically sealed and not exposed to heat, water, or air (oxygen) on a regular basis. CDs are plastic coated with a thin aluminum film, in most cases. Aluminum is a metal. It oxidizes (corrodes/rusts) slowly but surely when exposed to oxygen (air). Just like the sheet metal which the body of a car is made of -- except that sheet metal is thousands of times thicker than the thin metal film on a CD.
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