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

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

#141

Post by em500 »

thrdbndndn wrote: post #138

From my experience, commercial CD/DVD seem to have way higher quality and longevity than your personal CD-R/W etc. I've purchased lots of 80s second-hand CDs that often have awful case conditions and they all read totally fine (as in, the CRC32 checks out with online database). Is there a reason for that? Do they simply use better material or they have better tech to write them?

Yes, the processes are very different. Commercial discs have physical pits pressed in the recording layer, while burned disks just use the laser to change the reflexity of the layer (which is some dye or phase changing alloy).

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

#142

Post by GnarfGnarf »

danielheath wrote: post #88
grishka wrote: post #58

Earlier quoted context omitted.

The problem with cloud storage is that it's a needy thing. You have to pay for it in periodic payments the whole time it exists. And it's also controlled by someone else. I do really wish there to be a type of storage medium that I could record, store somewhere, and forget about. And then when I need it years later, it would still be perfectly readable. Optical discs are indeed kinda that, but their reliability is hi…

A desktop CNC engraver can be had for $500. Stones are cheap. Archaeologists have read engraved stones after thousands of years of neglect!

You jest, but here's an idea: print a block of raised letters (like old typesetting) on a 3D resin printer (mirror the characters). Roll a thin slab of potter's clay, say 5"x 8". Press the text against the blank slab, fire the clay in a kiln, and voilà, your bio or other precious document will last like Babylonian clay tablets.

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

#143

Post by epmos »

OptionX wrote: 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-one else mentioned it, so I might suggest punched tape. https://en.wikipedia.org/wiki/Punched_tape

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.

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

#144

Post by Roark66 »

It would be really useful to have some storage media that can truly last 50 years. It is pretty disappointing that most of the media with useful capacity (dvd r etc) cap out at 20~50 years. I wouldn't trust the most commonly used storage now (usb thumb drives) with important data for even few years unless it was stored in triplicate.

Personally I think the best method of long term data storage is spinning hard drives stored disconnected. I have a collection of them that goes back decades (with important data duplicated on multiple drives) including my first ever hard drive bought in mid 90s. Of my entire collection only one HDD broke down (actually one of newer 1tb usb3 drives bought few years ago - it started clicking few weeks ago).

I can't vouch for the current spinning disc tech, but I distrust current SSD tech(SD cards and nvme included) more so my current data gets backed up to a set of spinning discs frequently.

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

#145

Post by Double_a_92 »

mrjin wrote: post #103
kalleboo wrote: post #77

Earlier quoted context omitted.

Just my photo library is over 1.5 TiB, there just not way to have long-term offline backups of that, you have no choice but to run and maintain a file server and cloud backups

1.5 TiB is not much really. Any mobile HDD will do. I've a whole bunch of them. Oldest were over a decade, no issues at all. The only issue is that they have to be labeled clearly, or you are going to have a hard time to find whereabouts.

You do realize that HDDs can randomly break, right? To keep a proper backup you need to have multiple copies of all your data and also regularly access / copy it.

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

#146

Post by nordsieck »

midoridensha wrote: post #69
pcf wrote: post #52

Earlier quoted context omitted.

Exactly the same here, except that I gave all those discs to friends. And I shudder to think how much time I wasted on all that archiving, when it ultimately wasn't worth it at all. Now, I'm still doing much of the same, but this time downloading movies, TV series, documentaries etc. via Snahp to my archive on an external HDD. The other day I suddenly had a realisation: Why on earth am I downloading 1080p films to wa…

The problem is that many times, the "originals" (or official sources) become unavailable. There's a ton of old 80s/90s DOS games and 8-bit games that we still have now because of digital hoarders. If it weren't for them, they'd be lost because the original companies are long gone and most people just trash stuff. Now look at how much stuff regularly disappears from video services like Netflix and Amazon Prime.

I'm just glad that netflix is still operating their disc rental plan. If you want to watch niche, hard-to-get stuff, that's one of the better options, IMO.

I legally can't recommend anyone copy/rip discs that they rent.

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

#147

Post by GnarfGnarf »

smarx007 wrote: post #104

Is anyone using M-disks and what's your experience so far? https://en.wikipedia.org/wiki/M-DISC https://web.archive.org/web/20130422110903if_/http://www.mdi...

I just started using M-Discs last month. Bought a compatible burner, a Pioneer Blu-ray Disc (BDR-XD07B), CAD $170. I'm pleased to report that my burning software (ImgBurn) worked fine with the new Pioneer DVD drive.

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

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

#148

Post by cronix »

gorbachev wrote: post #71
darkwater wrote: post #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 e…

I recently got rid of all my CD-Rs I'd use for archiving back in the day. Moved everything to a NAS and dumped CDs. 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 unreadab…

My earliest ones still read. My later ones mostly don't. I'm guessing the difference is the earlier ones were recorded at 2x speed (fastest that existed) while the later ones were recorded much faster (probably 8x or 12x), which means less laser burn in time? Really not sure. Either that or the yamaha drive was just much better than the later model plextor.

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

#149

Post by lynndotpy »

mrjin wrote: post #100
yosito wrote: post #14

Earlier quoted context omitted.

"Hard drives" don't necessarily last any longer than a few years either.

If you keep a domestic model running 24x7, you are probably right. But if you just do cold archive, my last check were after around 12 years, all drives spinned up normally without any issue. No noticeable data loss at all.

This is my experience as well.

Out of simple anxiety, I transferred data from a few drives (spanning 2007 to 2015). If there were any issues, neither my file manager nor the SMART status reported any.

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

#150

Post by HankB99 »

cdr wrote: post #54
Test0129 wrote: post #32

After quite a bit of research into this about a year back I decided to archive everything on archive-grade CD-Rs. 20-50 years is more than enough and realistically in the correct climate (a safe or something that humidity would have trouble getting into along with dessicants, etc) could last much longer. I evaluated magnetic tape, HDDs, and a few other options are CD-Rs are as good as magnetic tape (in longevity) and…

I've always only bought Taiyo Yuden media since ~2000. Every CD-R and DVD-R I still have that I've tried is still readable. 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.

I think I have a lifetime supply of TY media. I hardly ever use it. I don't even know if it is CD or DVD. I'd have to look. I wonder if there is a shelf life for the media before it is recorded.

I'm in the spinning rust camp. I use the ZFS filesystem which protects against bit rot and I usually migrate to larger drives every several years. And I have an off site mirror of my local storage. My only concern is what happens to it when I'm no longer able to manage it. I guess I need to leave instructions.

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