[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [ARSCLIST] DVD stability
I found your post most interesting. The latest long-life ad claim comes from
Verbatim for their "metal-azo" DVDs. Were they included in your study?
Naturally I'm curious, wondering whether you can support or deflate their
I'm in the process of ramping up for a major archival project (NARAS has
given a grant of $20k to conserve my analogue recordings from many
countries) so naturally I'm anxious to make an informed decision about
The Lewiston Archive, Recordings & Documentation of the World's Traditional
A paper will be published shortly in Restaurator that summarizes work that
I have done which compares the relative stability of various optical disc
formats: audio CDs, CD-Rs (azo, cyanine, phthalocyanine dyes with silver
gold metal layers), CD-RWs, DVD movie discs, DVD-R, and DVD-RW.
In this study, many more disc brands and types were examined than what is
presented in the NIST study. In particular, 11 different brands of DVD-Rs
where tested. I am also currently testing 4 more brands. In summary, the
DVD-Rs faired better than CD-R (azo) and CD-R (cyanine) but no where near
the stability shown by CD-R (phthalocyanine). DVD-Rs are not made with
metal layer and phthalocyanine dye. Instead, an azo or cyanine based dye
used that shows less stability under elevated temperature and relative
humidity and when exposed to light. I will post the reference to this list
once the paper is published.
Also, the NIST study shows good stability of sample D2, but the aging is
for only around 420 hours. My testing has shown that some samples show
stability for the first 500 hours of testing (at 80 degrees C and 85%
relative humidity), but then degraded significantly afterwards. This was
particularly the case with cyanine dye discs.
Senior Conservation Scientist
Canadian Conservation Institute