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Re: [ARSCLIST] CD-R dyes for archival uses
A good summary but with a few misconceptions. Some comments follow
(original snipped) based on our third-party testing experience since
1985:
Jerry Hartke
Media Sciences, Inc.
> Since the topic of CD-R has been raised again, I offer the following taken
> from various websites:
>
> Dave Radlauer
>
> BLER's (Block Error Rates) have gone WAY down. Also, all discs have
> always had to conform to very rigid Orange Book standards. Players and
> recorders, on the other hand, have not. And that's where the trouble
> lies. They can vary wildly in their ability to read and write to
> various media. So, at the end of the day the only thing that ultimately
> matters in CDR media selection is what works with YOUR CD burner and CD
> players. There is little rhyme or reason to this. Some discs work great in
> one player, yet cannot be recognized or may skip wildly in another.
COMMENT: BLER is one of the least important quality indicators. All
discs are not required to conform to Orange Book standards, and many do
not. Standards are expectations, not specifications. Our experience
indicates that conforming discs are writable and readable in all "good"
drives. That is what defines a "good" drive, since there is no standard
for a write or read drive. Non-conforming discs often work in some
drives but not in others.
> Preventing CD-R Errors: Step 3, Media and Recorder and CD-ROM Drive
> CD-R media, like any other recording media, is available from various
> manufacturers and distributors. Unlike other recording media, it has more
> incompatibilities with different recording devices. A 9-track tape,
> 3480 cartridge, 8mm tape, DAT, or 2120 tape is likely to work as well
> in one tape drive as another. Not so with CD-R media. Although the
> reasons that media works well in one drive and not in another have yet
> to be fully investigated and documented, the fact is that you will find
> that one or two particular brands of media will record with more
> reliability than others in your particular drive.
COMMENT: CD-Rs are no different than other forms based upon our past
experience with floppies, 4 mm DAT, and 8 mm helical scan tape. Also see
the above comment.
> The manufacturer claims that it has a data life of 100 years.
COMMENT: Most claims are based upon extrapolation of invalid data, as
described in a white paper on our website:
http://www.mscience.com/pub.html