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

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21–30 of 204 posts

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

#21
When I was younger I started doing a lot of personal mixtapes as a hobby. A few years later, I moved to "mix cds".

These are all made from my personal music collection (which is not backed up in optical media).

Just saying, because CDs to me became just a transient media to, say, transport music to my car's stereo[1].

Because of this I never really bothered about longevity, they are just digital cassettes.

[1] - Yes, I could replace my car CD player with something else, but now it's a nostalgia thing :)

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

#22

Earlier quoted context omitted.

Do we actually know that M-DISCs are much better than ordinary discs regarding longevity? I wasn't really convinced by the wikipedia page

For DVD (and the rare M-DISC CDR) yes. For BluRay there is nothing special about them.

Any references about the BluRay claim? Genuinely curious

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

#23
post #9

I used to be concerned about optical media longevity. I bought Taiyo-Yuden discs. I checked their integrity. I stored them carefully. But the format became obsolete (for me) long before the media degraded. Recordable discs are just too small for the backup use case I had. Optical drives are still available of course, but they are now rarely standard with a new PC or laptop, and soon will become specialist components,…

I was a fan of the matte white top printable taiyo udens.

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

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

#24
post #20

What would one use as a media for long-long-term storage, taking only into account the resisiliance of the ability to read the data from it? For example if you wanted to store data in a time capsule for like 100 or 200 and you where ganrateed the people on the other side had a reader capable of reading whatever media, and whatever format you chose.

Paper?

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

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

#26
post #20

What would one use as a media for long-long-term storage, taking only into account the resisiliance of the ability to read the data from it? For example if you wanted to store data in a time capsule for like 100 or 200 and you where ganrateed the people on the other side had a reader capable of reading whatever media, and whatever format you chose.

No matter the material, the storage conditions are crucial (sic). You want temperature, humidity, acidity, magnetic stability.

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

#27
post #19

> BD-R (dye or non-dye, single layer or dual layer) 5 to 10 years > BD-R (non-dye, gold metal layer) 10 to 20 years > BD-RE (erasable Blu-ray) 20 to 50 years I find hard to believe that info. Seems to be sustained by a single study. That would mean that bluray (specially the BR-R format) is a pretty flawed technology.

I haven’t seen a BD-R in my entire life. In fact, the only use of BR I’ve had is on the PlayStation. The technology came way too late.

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

#28

That longevity table is under archival conditions (climate controlled). The vast majority of CD-Rs I had, regardless of brand, were completely gone after 10 years of storage in an enclosed textile bag. CD-RW would barely last 2-3 years.

Brand / media quality also matters a lot. I had some cheapo bulk CD-R whose top (reflective) layer started flaking after a few years (stored in their sleeves in a cardboard box in a dry cabinet).

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.

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

#29
Totally anecdotal but just a month ago I opened a box from my last moving (ended 4 years ago...) and I found a CD-RW labeled "Backup 2001", which survived 5-6 relocations, even an international one. Well, I put it into an USB DVD player I have aaaand, it starts spinning and spinning and spinning, and nothing shows up in Nautilus. Looking at dmesg I see a few I/O errors on the device. Then, I try ddrescue [1], start extracting an image, leave it doing its work for a couple of hours and... magic! I have a perfectly mountable disk image!

I got to live again some >20 years old memories, pictures of younger me with my friends. stupid things you would save as a late nerd teen with access to the Internet and a ton of emails in Outlook Express format (guilty!) that I could not open yet. I guess the format is probably not super-hard to parse (most of the content is plain text actually) but since I'm here, if you know of something already existing to convert it to mbox/maildir it would be cool!

[1] https://www.gnu.org/software/ddrescue/

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

#30
post #20

What would one use as a media for long-long-term storage, taking only into account the resisiliance of the ability to read the data from it? For example if you wanted to store data in a time capsule for like 100 or 200 and you where ganrateed the people on the other side had a reader capable of reading whatever media, and whatever format you chose.

Granite.

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

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