Also, avoid those slim-line cases if they were designed for CDs. CD cases have a tighter hub-grip than DVD cases because of the risk the two polycarbonate layers of a DVD pull apart! Nigel Archive of Maori & Pacific Music -----Original Message----- From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf Of Jerome Hartke Sent: Monday, 8 August 2005 12:20 p.m. To: [log in to unmask] Subject: Re: [ARSCLIST] "Archival" DVD-R? > Multiple copies are an excellent choice, indeed, I would say a > necessary one. > > They should be on different media, both (or all) of high quality. > > I trust that by "seal", you do not mean hermetically seal the disc. > Keeping air out means trapping gasses in, which I believe is > considered unwise for recordable optical media. Of course, you are > correct that a master copy should not be accessed except to verify integrity. > As usual, Mike is quite correct. I might add incorrect volume and file structure logical errors as a third, common source of premature failure. Such discs "work" in some operating systems, but fail is others or later versions of a "good" O/S. Jerry Media Sciences, Inc.