Storage: Do burned CDs and DVDs have a shelf life?
- 2/13/09 2:55 PM
Always have more than one Backup
by waytron - 1/31/09 4:24 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
The question “How long do Burned CD-Rs and CD-RWs Last?” was asked a few years ago in the Cnet Community Newsletter on 1/27/06 and to the best of my knowledge, things have really not changed much since then. Barry W. had a great answer to this question at that time and I would be hard pressed to really add anything of any real value to it. However, in my personal experience over the years, I have seen just about every scenario from some burned CDs starting to fail due to oxidation or delimitation in only a few months to many still working great after 10 or more years. Storage may be a big issue because I noticed many of my burned music CDs that I left in my car, did not last very long at all. Actually the most common failure that I have run across is caused by human error. I can not tell you how many times I have had clients hand me backup disks to help recover their failed hard drive only to find them totally empty. They thought they were backing up and really had nothing. The other common error is not backing up the correct folders. Many people often overlook data such as Quicken or Quickbooks data that may be stored in folders outside of My Documents or even hidden folders that contain Address Books, Outlook or Outlook Express data. If the data is important to you, my best recommendation is to never rely on a single backup. Have multiple copies of the same data on different types of media. Maybe use different brands of blank CDs, have a backup on an external hard drive as well and maybe even use an online backup source such as Carbonite or Mozy. And last but not least, TEST your backup by trying to recover something off of it.
Dana
Wayland Computer
Shelf life of CDs and DVDs
by charliekr - 1/31/09 5:12 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
The answer can be found at this site:
http://www.clir.org/pubs/reports/pub121/sec4.html
Do Burned CDs & Dvds Have a shelf life ?
by easyman55 - 1/31/09 5:24 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
As long as they are kept in good condition and you still have an opticaldrive that can read them they should have a life expectancy of 100 to 200 years or more. I am not so sure about the rewrite
DVDrw CDrw as they can be rewrote so will degrade a dit faster how ever these discs should still be stable enough to outlast the current CD or DVD technology these discs should have a life expectancy of 25 years
Should Last Forever, But Only If Undamaged
by Flatworm - 1/31/09 5:52 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
As long as they remain undamaged, CDs and DVDs, whether bought in a store or burned on your own PC or recorder, should last virtually forever. They aren't going to flake, cloud up or go unplayably brittle like old video tapes, which have a shelf life of only maybe fifteen years under normal conditions.
HOWEVER, you must treat them carefully if you want them to last forever. Be sure not to scratch the bottom surface or they might become unreadable (although such scratches can usually be removed). Strangely enough, it is actually more important to keep the label side protected from damage, because it's much softer. If it gets penetrated -- even the tiniest breach -- it lets air get into the actual recording media beneath the surface which will corrode the metallic material and render the data permanently unreadable.
Like a lot of things from cars to spouses, treat your CDs and DVDs with respect and care and they can last forever. Fail to do so and you risk losing them.
CD & DVD life span
by kuppa.jeaux - 1/31/09 5:56 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
Yes CD's & DVD's have a definate life span over time, but at this point it is only a theory suggested by the mfg's since no CD has reached this life span. Unless your plans are to pass then down like photographs, which also detoriate, you will not outlive the CD's anyway. If you have concerns about your CD life span some mfg's make what they call a medical grade CD which has an extended life, again it changes according to the mfg. I might add that the price also goes up with with the medical grade CD's. I do think it wise to have more than one copy of anything that is critical.
Answer
by Green_Toth - 1/31/09 6:07 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
Yes. Your friend is wright. Any CD or DVD contains self date of himself. Reason is that emulsion on CD/DVD isn't undead and, after some time, may contains error on it.
P.S. I'm sorry because by bad English
Do burned CDs and DVDs have a shelf life? Not really
by Jacque007 - 1/31/09 6:12 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
According to the motion picture industry there isn't an expected period when DVDs will no longer work or be readable. Currently the motion picture industry is working to transfer all of the old classic movies from the original reel to reel tape to the safer media of DVD. Some of the old movies have been lost or just sections of the movies are gone forever. A perfect example is the 1937 movie 'Lost Horizon'. When they got around to saving it there was over 25 minutes that was damaged beyond repair.
If the motion picture industry has faith in the DVD media so should we. You can be sure they have checked it out better than most of us can. You will find though that the Blue Ray media could dissappear in the not too distant future due to the fact they already have things recorded on DVDs and the Blue Ray technology is a lot more costly to produce.
With your CDs and DVDs, just keep them clean and free of scratches and they should last at least through your lifetime. Look at how well the LP Record has lasted. And remember that most land fills don't want anything plastic because it never breaks down.
Life depends on quality - here are my experiences
by TonyGore - 1/31/09 6:19 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
A few years ago I bought two large boxes of blank CDs in jewel cases. I use mine over a period of time, but my son who was a student did not use his immediately. When he came to use them, they had gone what is best described as "mouldy".
"Pre-recorded CD/DVDs" are created from a master and pressed - much like the old records were. Thus they are mechanically created, and are robust and with a long life.
Those you write yourself use a laser to cause chemical changes in a very thin layer within the CD. Moisture, heat, cold - all of these can affect them. Dual layer DVDs actually have two lasers that write at different depths. Experience and what I have read tends to suggest that just as floppy disks written on one machine were never guaranteed to read on another, so there may well be more variation on dual layer DVDs lading to less interchangeability.
I doubt that the CD or DVD drive you use to read the CD/DVDs in a few years time will be the one you wrote them in. Even now, you may have troubles - my desktop will only handle 4x DL DVDs as I discovered to my cost when I found that I had bought 2.4x DL DVDs. I had always assumed (wrongly it turns out) that a 4x drive would handle 2.4x disks, but not the other way around.
This leads to my rule number 1 - do not use the latest and least interchangeable technology for long term use, so I personally would not use DL DVDs.
You can buy archive quality CDs - they are more expensive. At the very least, buy from one of the companies that has manufactured computer storage media for decades. They have a quality and reputation to uphold.
This is my rule number 2 - for anything that is precious, use archive or high quality media.
I have a mantra that I repeat to all my customers - "there are two sorts of people - those who have lost data, and those who will".
This leads to my rule number 3 - always have two copies. However, don't make these two copies on identical media from the same batch. Use different ones. For example, with digital photos, every few weeks that you have taken them, as well as storing them on your hard disk, write them out to a CD. Then when you have about 6 CDs, put them onto a DVD, so that you now have two copies on different media.
I believe that the actual active layer is quite close to the top surface, and that you should only use special marker pens because standard ones contain solvents that might interact and affect the layer.
This leads to rule number 4 - only use special marker pens designed for CD/DVD use.
Now to my next rule - rule number 5. Store them in a place with relatively low humidity and a stable, reasonable temperature. Most equipment designed to play CDs and DVDs is going to be indoors (low humidity) where the tempertaure is a reasonably constant 20-22 degrees C (68-72 degrees F). If my understanding is correct, CDs and DVDs are actually built up of layers. Some of these layers will have different thermal coefficients, so the more temperature changes they are exposed to, and the greater those temperature ranges, the more thermal stress they will be exposed to. In turn, this can put stresses on the microscopic chemical changes that form your data. Now the data has been designed to deal with errors e.g. with CRC checks, but not with significant errors within the same area i.e. it may be able to correct one bit error in a byte, but not two. Excessive heat is probably bad, as it is mostly the heat caused by a laser that is used to cause the chemical change.
Finally, there is a second part to storage - what you store them in. I store mine in proper CD sleeves or cases. When I used to store photographic negatives, the better quality storage was special acid free paper/plastics. Because CD/DVDs are a similar process, I spend a little more and get quality sleeves. Then I keep them in a dark cupboard. After all, they are heat sensitive, and there is always the chance of sunlight passing through something that concentrates it - this is how fires start accidentally.
So rule number 6 is to keep them in the dark and in proper quality storage.
I have now dealt with the media and its storage. However, you can take a few precautions before creating the media. Make sure that you can read a disk written in your CD/DVD writer in a number of other machines. Do NOT utilise the modes some tools provide to squeeze on a few tracks extra of data. Some of these are outside the standard and may not be supported properly in the future.
And here is one that might suprise you - do not record your data onto CD/DVD with high level music blaring out. The vibrations may adversely affect your writer. (There is a video of someone singing loudly into the front of a RAID array in a data centre, and you can see that it causes all sorts of data errors, which the RAID corrects, but at a perfromance cost. Your data is being written without any of these benefits of redundancy).
If you are really worried, then it is worth every few years getting out your data and copying it onto new media. For example, copying your important data that you wrote onto CDs 5-10 years ago would only take 20% of the number of DVDs and you would know that it is still good.
Remember my mantra - "there are two sorts of people - those who have lost data and those who will". You can never totally prevent data loss, but you can do a lot to reduce the chances. Look at it another way - if you had to take it to a data recovery specialist, it would cost you thousands of dollars/euros/pounds. Against this, paying a few pennies/cents more for quality media, taking the time to check it and store it properly is probably a worthwhile investment.
Life depends on quality
by Irshad Siddiqui - 2/15/09 11:54 AM In reply to: Life depends on quality - here are my experiences by TonyGoreThanks Tony. You have given us a lot of necessary knowledge about the topic.
Solution = Archival Grade Gold CD-R's / DVD+-R's / & BD-R's
by Winchester257 - 1/31/09 7:13 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
Most recorded discs will become unreadable ( according to accelerated againg tests ) after 15 to 30 years.This is because of oxidation caused by the earth's atmosphere.
The best solution for long term archival applications is to use archival grade gold recordable discs.They contain actual gold in the recording layer which resists the oxidation caused by the earth's atmosphere.The accelerated aging tests on these discs are much more promising.Gold CD-R's are estimated to last around 300 years,gold DVD+-R's are estimated to last around 100 years,and the recordable gold Blu-Ray discs are estimated to last a little bit more than 100 years.
The color of the top of the discs is irrelevant.There are discs with gold colored top labels (Ativa Brand is an example) that are not archival grade gold discs.The bottom,recording side is the important part.Examples of companies that have Archival Grade Gold recordable discs are MAM-A (Mitsui),Kodak,Delkin Devices (E-Film),Verbatim,and Quantegy.
Of course it is always a good idea to make two copies and to keep the two copies in two different places.These Archival Grade Gold discs out-last hard drives by far.
archiving
by JOHN A. JOHNSON - 2/15/09 12:53 PM In reply to: Solution = Archival Grade Gold CD-R's / DVD+-R's / & BD-R's by Winchester257I have three grades of archiving. Really important on MAM-A. Important on Fuji. Less important on TDK. When I make a master on either of the first two I make a backup on TDK.
Cd & DVD shelf life
by Gladiator13 - 1/31/09 7:32 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
Dirty Little Secret #1:
The Shelf-life of a DVD-R/+R is ONLY 2 to 5 years.
They may last longer depending on quality and storage(don't buy those cheap 50 DVD's for $5.00 sales). Non-commercial DVD's are a chemical on a disk. The chemicals are heated by a laser and made to contain the info being copied to them. Over time this rearrangement of the chemicals will deteriorate. DVD movies, etc. are produced a completely different way and will last a whole lot longer. Buy top of the line DVD's, keep them away from heat and light, and otherwise protected and they should exceed the 2-5 year expectation. But there is NO guarantee. Remember digital info on a CD/DVD will keep working until corrupted, then will drop off the face of the earth.
The Bottom Line
by waytron - 1/31/09 7:43 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
As you can see from the postings so far, there is no single or correct answer except DO NOT TRUST ANY single backup. We have numbers here that range anywhere from a few months to over 200 years. So which are you going to believe? The variables are too numerous, so your best solution is to backup often, keep multiple copies on different forms of media.
Cd Dvd's Shelf Life Answer.
by seking0011 - 1/31/09 8:01 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
Cd Dvd's Shelf Life untill now it is not determine just yet,
there is a study going now but it is going to take
about two years to find an (acceptable answer)
but for those who want's an answer today,
here is your answer. (Unofficial)
base on my own experience i had cd & dvd's that won't play
due to several factors.
1.type of dvd/cd (- or + )
2.quality of cd/dvd (memorex/sony e.t.c.)
3.Type of burner in your pc or laptop.
4.where do store your cd/dvd's (cold/hot/dust place)
5.do you take good care of your cd/dvd's? (no scratches)
6.type of burning software (Nero e.t.c.)
7.version of burning software.
8.type of o.s. in p.c. (Win 98/xp/vista)
9.Number of apps. running at time when burning cd/dvd.
10.burner speed when creating a cd/dvd.
All of this facts are consider user's errors
because most of the people DO NOT UPDATE software
or o.s. system, and some users force burning beyond
there system capacity.
as i stated before this facts are base on my own experience.
And also for those who believe that having an external
hard drive to store your files is safe? think again.
any storage device (usb stick/cd/dvd/external h.d. e.t.c.)
no matter which one, it could fail at anytime.
and your data will be lost unless if you are willing
to pay big bucks to retrieve it.
if you want a better understanding on this topic
I recommend to visit the following web site.
is loaded with lots of info.
http://www.digitalfaq.com/media/longevity.htm
last for decades, depending.
by reefurbb - 1/31/09 8:59 AM In reply to: Do burned CDs and DVDs have a shelf life? by Lee Koo (ADMIN)
1. understand how opticals are made:
There is the top printed surface and the bottom plastic coated surface. The laser pulses through the bottom surface
to the underside of the printed, metal coated, surface. Home-burned cd's aren't as strongly burned as retail software
ones. One reason cd's seem to go bad is simply because the cd drive laser gets weak from use; i.e. a retail cd may
read but a home-burned one may not.
2. If you scratch up the bottom plastic surface, the cd may not read; microscopic scratches can happen and build up
with every use, to the point of looking cloudy. If you heavily scratch the top side, the cd will not completely
read. Hold the cd up to light and if you can see light through it, it may be compromised, unless the scratch is not in the
written area.
3. Sunlight and moisture are the two main other enemies of a cd. Sunlight can warp them, or the light can fog
the bottom plastic surface. Liquid or high moisture can cause the top layer to lift or curl.
4. If you can safely store and use the cd's, they should last decades. Unlike tapes, magnetism won't affect them.
5. Some brand cd's burn better and may be more resistant to concerns mentioned,which is the only reason they would seem to last longer.
6. Yes, make a dupe of ANY cd, one to use and scratch, and one to re-copy from.
| Forum legend: | |
 |
Locked thread |
 |
Moderator |
 |
CNET staff |
 |
Samsung staff |
 |
Norton Authorized Support team |
 |
AVG staff |
 |
Windows Outreach team |
 |
Dell staff |
 |
Intel staff |
