Even with the inflated prices nowadays 3tb 3.5" sata drives are cheaper than 2.5tb LTO-6 tapes.

I really wish a multi-terabyte optical media solution took off, because that would be the path I’d ultimately take, instead of going with expensive LTO devices and media.

> While the immediate burn quality seems relatively satisfactory, I was still not satisfied as to whether these discs were truly worth their premium over commodity blank media. Looking at the discs, it seemed that the recording layers were likely made of similar materials based on the visual aspect, unlike the obvious difference with DVDs. Also, it seemed that regular recorders were intended to be able to record to the BD-R’s (according to the Verbatim text).

...

> 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.

...

> From my research into the data, it seems likely that the M-Disc BD-R is not substantially different from other quality BD-R discs on the market as they all use inorganic recording compounds (with the exception of BD-R LTH of course). From a visual inspection, the disc appears the same bright chocolate-brown, unlike the obvious distinction with regular dye based DVDs and the M-Disc DVD which was a silver-grey. But my main concern lies in the demonstrated lifetimes of quality BD-Rs which are similar to the M-Disc DVD (to which the M-Disc BD-R is claimed to have also achieved). In essence, it appears that the MKM/Verbatim BD-R DL has already reached the same level of endurance as the M-Disc DVD had claimed without being “special” at all. It is thus, hard to justify paying more for an M-Disc BD-R, and I cannot really recommend it.

The "not really M-Disc" stuff comes from a post somebody made on the "Data Hoarder" Reddit board a few years ago. The discs were changed to enable higher burning speeds which resulted in a slight difference in appearance, but he/she didn't seem to have realized that Blu-Ray M-Discs were never substantially different from BD-Rs and instead assumed that the tweaked discs were more of a scam than the originals.

- A photo album extended with a curated set of photos each year. The real deal!

- NAS at home and blu-ray off site (parents home) for all photos

The problem with archiving data is you always need to be prepared to use the "next big thing" once your preferred method becomes unobtainable.

I currently have :

- Photos in iCloud (Live working copy)

- Backup at home on NAS (updated nightly, snapshots)

- Backup in pCloud (lifetime, mine or theirs, no illusions, hopefully lasts a couple of months if I die unexpectedly)

- Yearly archive on external HDDs, identical copies stored in separate locations, clearly labeled "Photo backup". No encryption, no archiving, just plain APFS formatted drives that can be plugged into a computer and read.

- Yearly archive M-disc blu-ray discs, again, identical copies, stored in separate locations. One disc per year labeled as such, ie. "Photo Backup 2020". The idea being you restore them in chronological order and have a complete set.

Or just keep it attached to your system, so spyware, adware, and the NSA will make free backups for you!

Most enterprise gigs I've worked sent them to Iron Mountain or equivalent.

A few months ago I needed to pull from an offline backup. The disk, which used CMR and was purchased new from an actual computer supply company (i.e. not Amazon), was burnt in for about 72 hours before it was loaded up with data and shoved in a padded box. Ten years later, the drive was pulled, and there were so many media surface errors that most of the data was unrecoverable. (I haven’t bothered opening the drive to see if there is some obvious sign of what exactly failed.)

In my case the backups were created in multiples using two different brands for exactly this reason, and the second copy was fine. But I wouldn’t say it’s the case a single magnetic disk can take the place of BD.

Mechanical disks are also getting expensive. The disk purchased to replace the failed backup was being sold at three times its original release MSRP. Some of this is due to the AI hysteria but some of it is also that the market is shrinking and becoming K-shaped.

Comically untrue, and trivial to verify that it is.

You obviously need to store the data in a physically remote place like your shed, car

Let's make it worse by keeping them someplace with terrible environmentals.

If you're gonna be wrong, don't be just a little wrong...

I also have a binder full of DVD-Rs, of about the same age and containing mostly the same data, that all read perfectly with no issues.

You're asking for trouble if you count on just one backup solution to keep your data safe.

It is absolutely not safe for many decades. If you haven't encountered any drive failures yet — you're lucky.

> A hard disk is cheap and stores several Terabytes

You should check prices again, I wouldn't say cheap considering price bump during the last year (or around so). M-Disks are way less convenient, but pretty reasonable for their cost.

I have so many photos of vacations and people who I've buried over the years, that I don't want to lose.

So I was thinking about using Blu-ray M-Disks as well, these last couple of months.