Re: [ARSCLIST] New CD Report NIST

[Rick Taylor <rtaylor@xxxxxxxxxxxxxxxxxx>]

This report is available for download from the AES:  "AES35-2000 AES standard
for audio preservation and restoration - Method for estimating life expectancy
of magneto-optical (M-O) disks, based on effects of temperature and relative
humidity."

http://www.aes.org/standards/b_pub/aes-standards-in-print.cfm


--
Rick Taylor
Graduate Research Assistant
DLSD - Audio Digitization Lab
University of Texas Libraries
The University of Texas at Austin

PCL 3.106  |  Mail Code S5471  |  PO Box P
Austin, TX 78712
Phone: 512-495-4439
rtaylor@xxxxxxxxxxxxxxxxxx  |  www.lib.utexas.edu


Quoting Steven Smolian <smolians@xxxxxxxxx>:

> This is a question for Mr. Hartke:
>
> Apart from your own report on CD testing, can you suggest a readily
> available web source which discusses the same issues, preferably one which
> does not come from a professional testing service?
>
> Steven Smolian
>
> ----- Original Message -----
> From: "Jerome Hartke" <jhartke@xxxxxxxxxxxx>
> To: <ARSCLIST@xxxxxxxxxxxx>
> Sent: Monday, December 13, 2004 3:14 PM
> Subject: Re: [ARSCLIST] New CD Report NIST
>
>
> > As mentioned before, BLER alone gives misleading results for accelerated
> > aging as reported at http://www.mscience.com/longev.html
> >
> > Jerry
> > Media Sciences, Inc.
> >
> >> -----Original Message-----
> >> From: Association for Recorded Sound Discussion List
> >> [mailto:ARSCLIST@xxxxxxx] On Behalf Of Joe_Iraci@xxxxxxxxx
> >> Sent: Monday, December 13, 2004 10:07 AM
> >> To: ARSCLIST@xxxxxxxxxxxx
> >> Subject: Re: [ARSCLIST] New CD Report NIST
> >>
> >> I have performed a similar study that will be published in Restaurator in
> >> early 2005 (I will pass on the reference to the list once it is
> >> published).
> >> Accelerated aging was performed on CDs, CD-Rs (various dye types),
> >> CD-RWs,
> >> DVDs, DVD-Rs, DVD-RWs.  Many (much more than the NIST study) different
> >> types from different manufacturers were tested.  Results were based on
> >> BLER
> >> changes.  Conclusion was that the CD-R with phythalocyanine dye
> >> outperformed all other disc formats.  A relative stability ranking of the
> >> various formats was produced.
> >>
> >> The goal of the study was to assist individuals in making choices when it
> >> comes to optical media.  Making a  lifetime prediction is time consuming,
> >> expensive, and usually contains a lot of uncertainty.  I believe a more
> >> practical approach is examining relative stabilities.  Any study that
> >> provides information on how this media reacts is useful.  Granted
> >> reactions
> >> are occurring at higher temperatures and there is no guarantee that those
> >> same reactions will occur at room temperature, but if you had to choose
> >> would you trust media that withstood harsh accelerated aging (80 degrees
> >> Celsius and 85% relative humidity for intervals up to 84 days) and still
> >> had no E32 errors and low BLER or media that failed within the first 21
> >> days under these same conditions.
> >>
> >> Yes, there are other factors to consider like writing speed and
> >> compatibility issues, but the focus is on media stability in this case.
> >>
> >> In the above study, using either BLER or E32 errors would have led to the
> >> same conclusions.  BLER alone can sometimes be misleading, but generally
> >> not when it comes to monitoring degradation via accelerated aging.   As
> >> long as both are monitored I do not see a problem using BLER. This
> >> observation is based on the experience of aging and analyzing several
> >> hundred discs.  Same applies to PI errors for DVDs.
> >>
> >> Joe Iraci
> >> Senior Conservation Scientist
> >> Canadian Conservation Institute
>