such thing as disc data disappearing? how long do DVDs last?

maansingh169 · Member Joined: 15 Mar 2004 Location: USA, NEWYORK

now i bought really good memorex dvd-r and i am converting my crappy Princo Compusa dvds over to the memorex. now playing some of my compusa princo brand ones.....i get problems...like skipping......but no problems with memorex, (so far).......

here we go with the question. i was curious today and i used DVDInfoPro and examined a Princo disc i burned a while back. now I am not sure if this specific dvd is skipping or not, but with with dvdinfopro (freeware) there where no read errors when i did the test. do that mean that the dvd is fine?
my ones that skip, people claim they do because of bad burns. now if these ones are burn good, does that mean that it can still go bad? meaning can it just go bad, like floppys some times do...

iooi · Picky Bastard Joined: 15 Jun 2003 Location: Yorks, UK

How can i put this without being shot down in flames...
Seems some brands of disks (Pinco's) dont hold the data too well. It could be the dye is breaking down. I had a load do the same on me. They burned Ok played OK but after 6 months could you hell as copy them and playing was a nightmare.....
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lordsmurf · Posted: Dec 17, 2004 01:25

The ability for DYE to break down at a "fast" rate (months, few years) has been shown over and over to be pretty much impossible. It will, in many decades, start to deteriorate at earliest. The chemical reaction cycle won't happen in months or even a few years. "Fast" corruption of dye would happen in seconds if exposed to oxygen, so those rumors of glues decaying as air "slowly" permeates the materials is myth. That would cause insta-coaster, not take months.

(Want to test? Take a disc and a razor blade, then shave off part of the edge of the disc, and watch the air create an insta-rainbow, which is destroying the dye.)

EDIT: I've made this thread a sticky because the daily rate of posts asking how long media will last and if data magically disappears.

The answers are simple:

NO! Data does not just "disappear" off your DVD-R/DVD+R discs.

The more likely explanation for "bad media" is one of three things:
1) The media was not tested to begin with. It was authored wrong, files left off, etc. It was incorrect to start with, or bad media to start with.
2) The drive reading the disc has been damaged. Lasers have a relatively short lifespan. Both burners and ROM units. This includes DVD players, CD players, etc. It may also simply be dirty.
3) The disc has scratches, dirt, smudges, scuffs, film, or some other issue that causes the laser to refract light at a bad angle. A warped disc can also do this. Disc warping is a side effect of disc wallets and cases that do not allow the disc to stay flat. Wallets and sleeves submit discs to scratches and other abrasions (sometimes too small to see with the eyes).

How long will my DVD-R/DVD+R media last?

NOBODY KNOWS! Various labs have run "aging" processes on media, with varying results. Most show that media will last for decades without any problem. Some results have even shown that dye-based media will outlast pressed metal media.

TO INSURE YOUR DISCS WORK WELL AND LAST A LONG TIME,
DO THESE THREE THINGS:

1) Use GOOD media (DVD-R,DVD+R).
2) Verify the data has been successfully and flawlessly burned
3) Properly store the media

Edit: This post was ONLY about dye-based media (DVD-R, DVD+R). Phase change media (DVD-RW, DVD+RW, DVD-RAM) is entirely different. DVD+RW and DVD-RW can die, as the crystals inside can break down, and yes, it can happen in a matter of months (used or not!). DVD-RAM's phase change materials are more durable, and should last as long as dye. The phenomena known as "disc rot" is a process by which metal decomposes, and this is something only found in pressed metal (commercial release) media, like CD-ROM, DVD-ROM and Laserdisc.

.
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maansingh169 · Member Joined: 15 Mar 2004 Location: USA, NEWYORK

all summarized........correct me if i am wrong......

if my media burns perfectly, and i can play the dvd on my player with no problems and DVDinfopro shows no problems. and if i am not breaking that seal on the edge, theoretically, i have a 99% chance that the media wont go wrong....

iooi · Picky Bastard Joined: 15 Jun 2003 Location: Yorks, UK

MrMoody · Mad Eye Joined: 26 May 2002 Location: NTSC Land

I've seen mishandling destroy discs even with no visible scratches or damage. Flexing them creates microscopic cracks in the surface that cause read errors. It could be that cheap media uses cheap plastic that's more susceptible to this.

Espen · Member Joined: 06 Dec 2002

Well when I'm start burning DVDs a couple of years ago I first used such crap as PRODISC. Most discs did play correct after burning(some did not), however a couple of month later they had playback problems. Did not even play correct in playes that took almost all media. I did label these disc so that may have been the reason, however this have never happen to any other media other then PRODISC.

Skith · Member Joined: 17 Oct 2004 Location: Bottom of the ocean

Poorly manufactured media can degrade. I have seen photos of princo media, where along the edge the dye is actually oxydized (brown/yellow). I have also seen pics of discs that had "transparent spots" form near the outer edge. (sorry I didnt keep the links). Sunlight (UV) can also affect the dyes. There, however, are no hard numbers on how much abuse discs can take.

Regardless, I avoid cheap/bargain media like the plague. I mostly buy media with well known manufacturers/dyes. Taiyo Yuden, RICOH (branded as Maxell or TDK), and Maxell.

FYI, when buying "Memorex" brand, you never know who is manufacturing the media. It might be Prodisc, RICOH, Princo, or any of a host of others. It's kinda like a "grab bag." Do you like suprises?

To get an idea of who actually made the media (as opposed to what name it is sold under), try DVD Identifier.

In addition to the videohelp.com media section, take a loot at SpeedLabs.org. There is a nice list of Media codes there.

It basically comes down to "how precious" your data is. For my important stuff (family photos, work, etc.) I backup in duplicate or triplicate - to different media.

If your in the US, you can get good prices on Taiyo Yuden media at [url]www.rima.com[url].

- May your PRINCO rest in piece.
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Cholerabob · Member Joined: 09 Jun 2004

Well sorry to argue but i've had Pricos (first dvds when don't know better) and cds go bad. The Silver coating was coming of the discs after burning in minuscule parts barely visible to the eye. When played the first time they were ok. But after a moth or so, no good...

lordsmurf · Posted: Dec 20, 2004 10:20

BJ_M · Patron Joined: 30 Jul 2002 Location: Canada

of course the question becomes WHAT is a good archive format ... tape (as in DLT) has proven itself with proper storage .. ..

DAT storage and other tape store methods are dicy at best (specially 4mm) , 1/2" seems to fair better.

I would not consider VHS an archive format - D5 , d-beta, beta sp = yes .. at least for mid term (10+ years) , problem is, are the machines going to be around...

a LOT of stuff was archived on laser disk (by the gov. also - as well as lot of librarys and such) .. that has proven to be not always a great choice ..

only thing i know of that has really stood up is microfilm and even high quality film stock (properly stored) ... smile.gif
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csaag · Member Joined: 12 Aug 2002 Location: United States

Hmm, how long to we can write our own HD-DVD (or BluRay DVD)?
All those DVD-R discs will be copied to those disks in 5 years or so.
So will it really matter if DVD-R discs actually average out to 10 years???

Of course , then we can discuss how long HD discs last...

Fandim · Media God Joined: 19 Jun 2004 Location: Reno, NV

I'm going to have to add my 2 cents here, because I've seen this question *far* too often as well...

It seems a lot of people who are asking this question, are also major advocates of STICKY LABELS.

Do NOT use sticky labels, eventally, they start to bubble, especially if the DVD is played frequently, and it will very much destroy the balance of your disc. This will cause your disc to become unplayable in the worst case scenario, or may just add skips and bad choppiness towards the end. Hell - some lucky ones might not even experience a problem at all... Just a forewarning, do not be surprised when it appears your disc has 'magically gone bad', when you're using these labels.

Go buy an Epson R200 - they're cheap - and it wont be long until you've saved the amount you pay for it, just in the cost you'd pay for sticky labels alone. (Printable discs are no longer that much more expensive than non-printable, after all.)

Seth
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BJ_M · Patron Joined: 30 Jul 2002 Location: Canada

archaeo · Member Joined: 18 Mar 2004 Location: mountains

The National Institute of Standards and Technology has the following recommendations for DVD and CD storage:

http://www.itl.nist.gov/div895/carefordisc/disccare.html

In addition the NIST, along with the DVD Association (DVDA) and several government agencies, has formed the Government Information Preservation Working Group.
This group is working with the optical disk industry to set requirements for archival quality CD and DVD recordable media and to specify to the industry the minimum number of years that recordable CDs and DVDs need to last to meet their requirements. NIST researchers also are developing a test that media manufacturers can use to determine whether the CDs and DVDs meet the criteria for archival use. The National Archives and Records Administration (NARA)supported this project because there are no national/international standards for the longevity of optical disks that can assist managers in the federal government to select optical media for the storage of permanent records with a reasonable assurance of how long they may be stored on the media.

For further information on this program:
http://www.itl.nist.gov/div895/isis/datastorage.html#writable

Capmaster · Posted: Dec 20, 2004 13:47

Here is a pertinent GCN article on research done at NIST on recordables, as well as information about what's commonly called "laser rot" on pressed DVDs. Here's a quote about DVD recordables from it that is relevant:

BJ_M · Patron Joined: 30 Jul 2002 Location: Canada

archaeo · Member Joined: 18 Mar 2004 Location: mountains

cyflyer · Member Joined: 23 May 2004 Location: Cyprus

csaag -
"Hmm, how long to we can write our own HD-DVD (or BluRay DVD)?
All those DVD-R discs will be copied to those disks in 5 years or so.
So will it really matter if DVD-R discs actually average out to 10 years??? "

Why bother repeating all that work ? Its already digital info and will still be read by BluRay will it not ? All current dvd-r's should be read by all fututre digital sytems, BluRay's etc. At least thats what I have come to understand. If anyone knows otherwise now's the time to speak up !

lordsmurf · Posted: Dec 21, 2004 02:51

HOW DO I VERIFY MY DISC CONTENTS?

There are several programs that can be used to test the integrity of data.
Use something like DVDInfoPro or Nero CD-DVD Speed and run a scandisc. They also have varying speed tests and read tests. In Nero CD-DVD Speed, go to EXTRA -> SCANDISC and then perform a surface test of the data.

(Note: the "verification" feature in Nero Burning ROM is worthless. Do not waste time on this tool, as it often gives bogus results.)

Also put in in the PC, and read the contents of the disc. Make sure your files are there. And finally, put it in the DVD player, if video, and make sure it plays chapters at the beginning, middle and end.

No one test works 100%, but by checking with several softwares, and by verifying the information "by eye", hopefully you'll feel safe that the burn is good.
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Skith · Member Joined: 17 Oct 2004 Location: Bottom of the ocean

To add to LordSmurf's comments, creating a Checksum file is another way. The two most common types are SFV files (usually using CRC32) and MD5 files (Using an MD5 sum).

Some programs that will create these checksum files include:

CD Check *one of my favorites

FSUM *another of my favorites, command line only, supports a wide range of checksum algorithms (as well as combinations)

Quick Par - this one can create "parity volumes" that allow you to reconstruct data from a damaged disc. I have not used it. Instructions use lots of technical terms - be prepared to do some learning.
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dcassidy · Member Joined: 16 Jul 2004 Location: Munich

Hi,
I didn't wish to start a new topic as my problem seems to be similar to the main theme of this one.
1. I have a Sony DVP-CX850D.
2. It is about 4 years old.
3. All commercial DVDs can be plyed bothe Region 1 and 2.
4. I have created some DVDs using TMPGEncDVDAuthor from AVIs in NTSC.
5. Up until last month they all played correctly and perfectly.
6. Now the majority of them will not play as the message comes up "Insert Disc" and moves the carousel on to the next disk.

What does it sound like to you guts..

1. This DVD Rot ? I have always used Phillips expensive DVD+RWs.
2. The laser in my player (but all commercial ones play OK !!)
3. Some DVD Setting has erroneously been set.
4. NOTE: They (the DVDs) all still play perfectly on my PC DVD Drive.

Any pointing in some direction will be appreciated.

Cheers,

Dezzz.
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BJ_M · Patron Joined: 30 Jul 2002 Location: Canada

does a NEW burned disk of the same type play in it ?
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