[This article was first published in the January, 2006, issue
of
Larry's Final Cut Pro Newsletter. Click here to subscribe.]
From time to time
in this newsletter, we've had discussions about the life-span of
CD and DVD media. At a trade show recently, I had a chance to talk
to the engineers at MAM-A, one of the better CD/DVD media companies,
about the life-span of burnable disks.
Here's what I learned.
The life-span of
a burnable CD or DVD is highly dependent upon the quality of the
organic dye it uses. Not all organic dyes are the same. In fact,
organic dyes will vary from one product line to another from the
same manufacturer. (Want to know the technical name of the dye? Phthalocyanine.
No, I can't pronounce it.)
For example, MAM-A
Gold label CD/DVD discs have been shown in the lab to last 6 times
longer than silver label.
MAM-A estimates
their Gold label CD-R's have a life-span of 300 years and the silver
CD-R's of about 50 years. Other discs that they have tested look
like they'll fail in 2 years or less.
Due to differences
in organic dyes between CDs and DVD's, Gold label DVD's have a lab-rated
life-span of 100 years, if handled properly. MAM-A silver label CDs
and DVD's can start to degrade after 20-30 years.
Also, to improve
disc longevity, store CDs and DVD's in jewel cases, on edge, in a
dark and temperature controlled space. For those of you old enough
to remember, these are the same instructions we followed for storing
vinyl records.
Here's a link to
NIST which discusses the best ways to archive CDs and DVD's: http://www.itl.nist.gov/div895/carefordisc/
I'd been reading
recently about a concept called "CD-ROT." CD-ROT is caused
when a bacteria attacks the aluminum backing of a replicated CD.
Burned discs are generally not affected by CD-ROT.
Also, MAM-A recommends
that to improve data integrity and compatibility, burn your disks
more slowly. My recommendation is to burn CDs at 16x speed and DVD's
at 2x speed.
They felt that
those numbers were a bit conservative. As their engineer, Joe Weisenbach,
stated: "We see excellent results burning CDs at 16x, we have
not seen significant improvements in burning DVD's at speeds less
than 8X."
As a follow-up,
I sent MAM-A an email asking about the correlation between "lab-testing" and "real-world" testing.
They replied: "Who knows? We've only been making them for 12
years."
Go
to top.
Update:
Life-span of DV tapes
Bill Moede,
of Green Bay, Wisconsin (which I mention because it is near where
I grew up), sends in the following update:
I have also had
dropouts on older miniDV tapes, 4-5 years. For that reason, if
we are retaining material long term, I master to DVCAM. I have
DVCAM tapes that are nearing 8 years old with no problems.
I had also been
making backup masters on SVHS, I have of some of these tapes that
are still quite good after 12 years.
For a few years,
I was backing up to digital 8mm just using a digital 8 camera with
DV input, but I was seeing some dropout on those tapes after a
few years also.
Currently, we
are making backup emergency copies to Maxell Broadcast quality
DVD's. Yes, I know its compressed, but better that no video at
all!
Also, I do not reuse miniDV tapes more that 2 years old.
Uli Plank also
adds a comment:
[Larry wrote:] I
understand your frustration -- dropouts are not good. However,
I am DEFINITELY not a fan of archiving on hard disk.
Uli continues: Very
true! But in the case of very important footage, as long as it
is short enough, I'd rather consider optical media. Tape is very
sensitive to dust and magnetic fields, which are nearly everywhere.
DVD-RAM is a very robust long-term medium and "only" depends
on the availability of a reader (which may change it's connectors,
OS-support and such). And, well, even a tape needs a compatible
player ;-)
Larry replies: Thanks
to both Bill and Uli.
This tip is from the January, 2006, issue of "Larry's
Final Cut Pro Newsletter," a very cool FREE monthly Final Cut
Pro newsletter -- subscribe at Larry's web site: www.larryjordan.biz.
Larry Jordan is a post-production consultant and an
Apple-Certified Trainer in Digital Media with over 25 years experience
as producer, director and editor with network, local and corporate
credits. Based in Los Angeles, he's a member of both the Directors
Guild of America and the Producers Guild of America.
Any references to trademarks or products are used for
editorial purposes only. Text copyright 2005 by Larry Jordan. All
rights reserved.
