Inexpensive Blu Ray Media

[JoeThePhotographer]

I've seen blu ray media for $1.50 per disk (Verbatim) and some even closer to $1 per disk (Memorex).

All of these inexpensive disks use LTH, which means that they use dyes and are made in converted DVD manufacturing facilities, hence the reduced cost.   Two drawbacks of LTH technology is that it is not compatible with every single burner (Verbatim has a compatability chart on their website) and is rated to burn at a slower 2X.

Besides the obvious compatabilitty and speed drawbacks, should these inexpensive LTH be mistrusted for archiving tasks where reliability is arguably more important than speed and compatability?

I haven't moved to Blu Ray yet, and the primary reason has been the cost of media.  At these prices, I can actually afford to move forward with a blu ray burner purchase, assuming these inexpensive disks are reliability.

Joe

[billseymour]

Like Joe, I am also interested in whether these inexpensive Blu-Ray discs are trustworthy. Thanks, Joe, for identifying the reason for the significant price disparity- I had been quite confused seeing such a price range for discs, and I now understand why the difference exists.
--Bill

[peterkrogh]

Bill,
A friend recently got bitten by this - the discs he bought don't work in his burner.  I as unaware of the compatibility chart.

In general, I think that a move to Blu-ray should be accompanied by an implementation of some kind of data validation procedure.  No matter what the theoretical longevity, that's just too much data to trust without verification.
Peter

[JoeThePhotographer]

Peter,

I supposed that means validaing all of your media at regular intervals, not just when you first burn it.  In that case, I am losing sight of how optical media can help me.  It would be faster and cheaper to have three hard drive backups.  Or is it the virus threat that makes optical media essential?

Joe

[peterkrogh]

Joe,
I would say that you don't have to validate all of it - but you should at least do a decent sample.

As to what you are protecting against, it's not just virus.  It's also bit rot - random flipping of bits on a drive. Additionally, there is also corruption in the volume information (overlapped files, for instance)

There's another one, as well. With a  hard drive archive, it's likely that you will want to update the drives periodically. Doing that without writing bad data over good is possible, but not easy. If you don't validate before each update, you are likely, at some point, to make this mistake.

You would also want to be very careful whenever you have all hard drive copies on line at once.  At that point you are susceptible to some electrical or volume problem killing all hard drive copies.

IF you don't want to use write-once, I strongly suggest using one copy of the hard drive versions as though it was write-once.  Hash it and don't update, except after a thorough validation.

The write-once copy - whether optical, disk or tape - plays an essential role as a disaster recovery copy of the files.  Optical disk just makes it more achievable for most photographers, IMO.

Peter