Eric Smith wrote:
It was my understanding (perhaps wrong?) that RW media
uses a phase
change to store the data, and that it takes significantly more energy
to induce the phase change than to induce a chemical change in dye
for write-once media. That's why it can't be written as quickly.
If it really works that way, one would reasonably expect RW media to
have *better* longevity than write-once media.
Based on my experience, this isn't true by a longshot. After no less than
three occaisions where I have lost data stored on DVD-RW media (all three with
different media brands), I stopped doing it. I only use rewritable media for
testing burns now, never for archival storage.
As for the topic of "how long does DVD-R media last?", I feel it's
irrelevant
because newer, popular standards come along every decade and we retrofit our
data to meet them as it inevitably grows. From personal experience:
1985: Stored my data on about 100 360K DSDD floppies
1990: Purchased computer with 3.5" DSHD drive; copied my 360K floppies to
about 25 DSHD disks.
1993: Data grown to 200 DSHD floppies; stored all of them on single QIC tape.
1996: Data grown to 4 QIC tapes; stored all four onto two CDRs.
2002: Data grown to 200 CDRs (blame broadband!); spent a week merging
duplicates and deleting redundant info, recompressing to more optimal formats,
burnt them onto ~30 DVD-Rs.
2005: Data grown to 200 DVD-Rs; archival storage is 3-4 DLT7000 tapes.
For extra paranoia, I never threw out any of the older medium (although I do
recycle the disks as necessary, like when I need a spare 3.5" to make a boot
disk or something).
--
Jim Leonard (trixter at
oldskool.org)
http://www.oldskool.org/
Want to help an ambitious games project?
http://www.mobygames.com/
Or check out some trippy MindCandy at
http://www.mindcandydvd.com/