I would assume that Kodak bases their results on measurements during the accelerated ageing and light exposure processes only of BLER for CD-R and its equivalent PIE (or PIESum8) for DVD-R. Such measurements are usually misleading, as reported in our technical white paper published on our web site at http://www.mscience.com/longev.html . "Test data did not identify one universal end-of-life indicator, probably because of the diverse media sources included in this study. BLER was a poor indicator, showing acceptable results for samples that failed other important quality requirements." Again, gold is one of the least important factors that influence longevity. The recording drive and write speed is very important, as is the general design and quality management of the media manufacturing process. I am sorry to see misleading information based only on marketing claims, but am thankful that I am not responsible for the resulting archives. Jerry Hartke President Media Sciences, Inc. > -----Original Message----- > From: Association for Recorded Sound Discussion List > [mailto:[log in to unmask]] On Behalf Of Jos Van Dyck > Sent: Saturday, December 06, 2008 9:23 AM > To: [log in to unmask] > Subject: Re: [ARSCLIST] DVD-R recommendations? > > Kodak states for the new Professional Gold DVD-R media: > "Kodak professional discs have been tested under light and accelerated > aging > to preserve 200 years with proper handling." > http://www.alkemy.eu/gold_professional_dvd.html > > MPO (France) make gold DVD-R and DVD+R for libraries and archives. > http://www.mpo.fr/documents/catalogue/gamme_dvdr.pdf > > Cheers, > Jos