Longevity of Recordable CDs, DVDs and Blu-Rays (2020)

For my photo history I prefer to keep PAR files next to it. On a running mechanical disc I haven't seen issues when running the repair. I do expect to see some errors in the future and as long as it stays under a certain percentage, things will be fixable.

I started doing this long time in the past, when harddisks were awful. I would often lose mp3 files due to damage. With mp3 you can easily hear it. With jpeg images you can often see damage as well.

The earliest CDs I had were from 1994 or so, though most were from early 2000s. They were mostly cheapest CD-Rs you could buy back then, so I was expecting most of them be completely unusable.

But most of them still read perfectly. I had maybe half a dozen (out of hundreds) that were completely unreadable, mostly due to peeling, about a dozen that were functionally unreadable, because there were so many unreadable files I couldn't save anything complete out of them, and maybe 10% that had less than 10 unreadable files on them.

I was surprised. I was really expecting almost all the early ones to be dead.

https://learn.microsoft.com/en-us/windows/win32/stg/structur...

e.g. https://www.mitec.cz/ssv.html

http://fileformats.archiveteam.org/wiki/Outlook_Express_Data...

Back in my sharing early days, I probably had like 1000+ dvds of anime, movies, hk film, games etc easily.

I had so much media that I didn't have time to watch it all, let alone watch it again in the future (there are some gems that I actually went out and purchased retail copies).

Plus alot of the shit would get released at higher quality making my archive obsolete (not always)

One day I just chucked it all out.... Years of archiving, downloading, burning ripping.

Was a waste of time and money in hindsight

IMO, the #1 use case for optical drives is probably playing music in the car. For anything old enough that it doesn't have an aux port, it's the best solution.

* Tape adapters add a lot of noise. Maybe different drives work better than what I've got, but I tried and it's totally unworkable

* Short range FM adapters are terrible. Similar noise to tape adapters and the quality is really prone to degradation depending on the EM environment.

The stock of older, working cars is quite large. Eventually it'll get used up (outside of enthusiasts), but that'll probably take a few decades longer.

And as long as people are listening to CDs in their cars, there'll be a demand for the ability to burn them.

I have not been able to buy these in the last few years. Also, when I was able to buy them, one had to be careful of counterfeits.

Do you have a source for them?

Taiyo Yuden at least used to be white labeled sometimes, so you'd just look up online what white-label media at Best Buy or CompUSA at the time was Taiyo Yuden.

I haven't burned a disc in probably close to a decade at this point though. SpiderOak is my backup.

>Digging further around the M-disc site, it is noted that their section on longevity testing actually features no data about the BD-R discs at all. Indeed, if there were tests, the reports were not actually featured on the site at all. Further poking around in M-Disc Technology pages shows only references to their DVD products. In fact, it seems their patented “etched in stone” material may only apply to their DVD products.

https://goughlui.com/2015/10/16/review-tested-verbatim-lifet...

That said I still have a lot of cheap CDs from 20 years ago that still read fine as well.

I've had a 25GB M-DISC BD-R kicking around on my desk without a sleeve or case for a while now to test durability. Sometimes I take it outside and leave it on my patio table for a few days to add some extra wear. I slide it around the desk, pick it up with normal greasy/dirty hands and handle it non-gently, flex it a bit, wash it off in the sink, and wipe it off with a cotton cloth. After four years of this abuse so far it still hasn't lost a single bit of data. I have noticed some of it takes a bit longer to get a good read so I'll probably lose data soon but this has been a hell of a lot of abuse so far.

I’m a huge fan of mdisk but I’m not sure it makes much sense in the era of cheap cloud storage. There are many companies now that will give TB of storage for 9$/month. Also there is cheap archival storage on AWS.

At $10 a pop, one is very prudent when choosing what to backup.

There is a reason ancient documents are found in Egypt "all the time" and almost no place else in the world: Egypt is an ideal climate to store paper. The rest of the world paper will decay in a few hundred years. (of course modern technology can create better conditions - if we choose to keep it running)

* Higher data density => tighter tolerance => same physical degradation is more catastrophic (DVD ~7x density of CD, BD-R ~20/10/5x DVD density = up to 140x CD density)

* Produced later and therefore like all consumer goods, less regard for durability and more regard for absolute cost optimization

However, these don’t really have a use for consumers. CDs had music, DVDs and Blu-rays had television and films, but there is unfortunately no compelling use case given home media is turning to streaming. Additionally, for many, cloud storage is replacing the need for local storage in spite of its drawbacks.

Many contract agreements would not allow you to keep the data, and you'd be more likely to be sued than paid!

But I agree that (maintained NAS >> removable media). :)

Edit: 100 - 200 years is probably 2 to 5 pandemics, some of which may be considerably worse than the last one; and plenty of time for fires, floods, storms, earthquakes, and/or war (civil or other). Granite has a track record. Some stainless steels might be OK too (not for much longer than 200 years, though).

1. https://en.wikipedia.org/wiki/Cleopatra's_Needle

the library of congress uses contemporary storage media (hard drives), and migrates everything to newer storage media as the previous media becomes obsolete and replacement hardware for that media stops being manufactured.

they have learned that stockpiling old reading hardware and software isn't sufficient to be able to read that media in the future.

they move everything to new media manually and archivists and volunteers work continuously to bring data on hardware more than one generation old into the current generation as everything progresses.

source: I read it in a detailed article about the LoC a couple of years ago and have forgotten where. :(

Fired clay tablets are much more resistant, but lower density (because clay), unless you use a dedicated press maybe (most of the ancient Near East clay tablets were actually fired fortuitously e.g. by a building burning down, that was only rarely intended and most tablets were used as erase-boards). But obviously non-tablet pottery can go through millennia in rather good conditions.

Carved wood is also a good idea, but it still needs good conditions and maintenance. Still, in the right storage it can last for centuries (see the Tripitaka Koreana for instance).

Leather, parchment, and vellum too, but I think then your main concern will be the degradation of the pigments.

If your focus is on longevity above all else, then you can’t beat stone. Though that can still be destroyed. I guess above stone would be highly non-reactive metals, however you’d need a metal which is not very precious as well (e.g. not gold, or silver, or platinum). I’m not very versed into metals and metallurgy, but I’d look towards titanium (it’s extremely reactive but not at normal temperatures), or bronze.

At one point there were disks made out of glass (versus the conventional polycarbonate), in theory that gives them infinite lifetime short of being physically destroyed. Though it does assume a compatible drive device.

We have family photos from the 1800s. Every bit of computer data I have from the 90 is gone.. except what I printed out.

There is always a trade-off between mass, durability, and data density. I know you excluded those considerations, but for only 200 years in a time capsule you likely don't want to use large stone blocks or stainless steel.

The tape has several advantages. Mylar is very light and kept in the dark at a constant, reasonable temperature is going to last two centuries no problem. You can read the tape by hand, if you need. An 8-bit tape is an inch wide and can be rolled into a canister for your time capsule.

Of course, for small amounts of data print English words on acid-free paper. For large amounts, tape is going to blow out the mass budget you didn't know you had because of it's low data density. But there might be a space in there somewhere for a tech I loved as a kid.

I'd actually expect such a CD to last tens of thousands of years.

For your requirement of 100 to 200 years, a pressed (not burned) CD might well be sufficient if the storage conditions are optimal (cool, dry, no oxygen).

[1] https://www.engadget.com/2006-10-22-near-perfect-glass-cd-hi...

[0] https://longnow.org/ideas/02008/08/20/very-long-term-backup/

"With appropriate, difficult to maintain, storage conditions, this film has a life expectancy of ~500 years."

https://en.wikipedia.org/wiki/Microform

Stuff from reputable brands still look great, but I haven’t hard had a CD or DVD player in years if not decades at this point so it might be a cesspool of data loss for all I know.

Exploration | geophysical | seismic surveys that "can never be repeated" ( the atmosphere | climate | ground has changed since ) and cost thousands to millions per day to acquire have troves of original copies - SEG-9 (SEG-21) track tapes, DAT tape, optical discs, that tend to be preserved "for reference" despite much of the data having migrated media-wise forward.

This is shown in the table from the parent article, where there are 3 rows for CD-R, the best, which were specified as suitable for archival purposes, but Kodak and the few other manufacturers of such CD-R have stopped soon their production, the second best, which were the original CD-R with phthalocyanine dye and then the other CD-R, whose expected lifetime is only half, with cheaper dyes, which were introduced on the market later.

Also, as expected, the table shows that the higher the information density is, the lower the expected lifetime is, when similar materials are used.

Most are fine though.

You are still in that range then

Better do recovery records, that way you would able to recover data and not only know it was corrupted.

RAR recovery records, if storing in an archive is okay, or PAR.

As for HDDs, I lost about a quarter to a half, with the rest just being obsolete these days. I can definitely attest from personal experience that hard disks from the same series tend to fail at the same point (I had 3 WD blue HDDs in a single computer, as system, data, archival disks; the system one failed, so I moved the system to the data one, which failed a bit after; so I retired the third one; failures happened at about the same runtime according to SMART data).

For any serious archiving i would consider M-disc Blu-Ray

http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www...