There is no theoretical reason that there should be a limit on the number of
times a tape with "sticky shed" can be baked.  The only report I have seen
that indicated someone had found a limit was retracted.  The person making
the report realized that the tapes thought to have been baked unsuccessfully
hadn't actually been baked.  He later baked the same tapes successfully.

Another report came out a few years back indicating that baking could cause
microscopic structural changes in the tape surface.  It was later discovered
that these tapes had been baked at over 70 degrees Centigrade rather than
the recommended "baking" range of around 50 degrees Centigrade.

One last comment from the peanut gallery dealing with a preservation issue
concerning analog tape.  We do a lot of disaster recovery work at our lab
and ferric oxide analog audio tape stands up to disaster exposure very well.
If we receive the tape within a few days of exposure, better than 95% of
ferric oxide analog tapes can be restored to playable condition.  Of the
balance, more than 95% can be partially restored so the content, if not the
full quality can be recovered.  This means less than 1/4 of 1% is lost.  You
don't expect to get those sorts of results with digital recordings that have
been submerged.  Of course, the best preservation strategy is redundancy in
geographically separated sites- but- if you only have one copy and something
happens, I'd place my bet on recovering the recording from analog tape
before digital tapes or hard drives.

Peter Brothers
(201) 440-6589

Restoration and Disaster Recovery Service Since 1983

> -----Original Message-----
> From: Association for Recorded Sound Discussion List
> [mailto:[log in to unmask]]On Behalf Of Watsky, Lance
> Sent: Monday, May 10, 2004 10:41 AM
> To: [log in to unmask]
> Subject: Re: [ARSCLIST] Analog Masters
> Steve,
> You made a very good point when you mentioned that "the costs of
> prioritizing are being driven by the need to first find out
> what's on them". I just had a conversation with a Archivist at a
> Religious Institution, who had a reel-to-reel tape from the
> 1970's that she believed needed to be transferred. After talking
> with her and discussing the possibility of the tape having
> "sticky shed", and different transferring options, she finally
> told me that she had no idea what was on the audio tape  and as
> such was having a very hard time raising the funds for the work.
> It would seem very clear that before an institution pays to get
> something transferred that they need to somehow listen to the
> recording, especially if the recording was never properly
> cataloged in the first place. The question however, is how to do
> it safely and economically. I wouldn't want to suggest that the
> master tape simply be played for fear of all the oxide being
> ripped off, but I have also read that there is a limit on how
> often a tape can be succesfully baked.
> What are your thoughts? Should every recording that can
> potentially have "sticky shed" be baked first, and then be
> transferred to an inexpensive user copy (or cataloging copy) and
> listened to before creating a preservation copy and further
> decisions are made?
> Thanks,
> Lance Watsky
> Preservation & Media Specialist
> The Georgia Archives
> 5800 Jonesboro Road
> Morrow, GA 30260
> 678-364-3764 (phone)
> 678-364-3860 (fax)
> [log in to unmask]
> -----Original Message-----
> From: Association for Recorded Sound Discussion List
> [mailto:[log in to unmask]]On Behalf Of Steven Smolian
> Sent: Monday, May 10, 2004 10:08 AM
> To: [log in to unmask]
> Subject: Re: [ARSCLIST] Analog Masters
> Another long-term problem is related to accessibility, accuracy and
> completeness of the data required to find out what's on the darned thing.
> I've dealt with the consequences too many time of folks who bring in 7"
> reels of tape, assuming they're 7-1/2 ips 2 track stereo of a
> family member,
> only to find it's 4 individual tracks, the speed constantly switched among
> 7.5, 3.75 and 1.87 ips,  some portions of which may be family
> members, some
> "hits of the day" with the mike in front of the radio speaker (I recently
> encountered a whole moon landing tape done this way with other stuff
> recorded over it in patches and at various speeds), and some live music.
> The scrawl on the boxes was completely uninformative.
> I recall an old science fiction brief story where they were able
> to get the
> entire content of the Library of Congress onto the head of a pin
> and had to
> put up a small moon-sized satellite to hold the catalog.
> In short, as we look at past artifacts, it is becoming clearer that the
> costs of prioritizing are being driven by the need to first find
> out what's
> on them.
> Steve Smolian
> ----- Original Message -----
> From: "Karl Miller" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Monday, May 10, 2004 9:39 AM
> Subject: Re: [ARSCLIST] Analog Masters
> > On Fri, 7 May 2004, Konrad Strauss wrote:
> >
> > > But do analog copies really make sense anymore? It is a dying format,
> most
> > > tape manufacturers are phasing out their analog tape lines,
> the same is
> true
> > > for tape machines. 2 questions come to mind: what guarantee do we have
> that
> > > present-day tape formulations are robust, and second, what are we to
> play
> > > these tapes on 40 years hence?
> >
> >
> > It seems to me that analog is just not economically viable, or
> > practical...however...some rambling thoughts...
> >
> > Having done some consulting for the State's Department of Information
> > Resources...they had some digital files that were 30 years old.
> We had to
> > send the tapes to the Smithsonian where they had a working tape drive.
> > Then the State had to pay a group of programmers to reconstruct the
> > software to read the files.
> >
> > I am reminded of the project, "Audio preservation: a planning study :
> > final performance report," published in 1988 under the Associated Audio
> > Archives. We still don't have the "universal" storage format recommended
> by
> > that study.
> >
> > For me, it doesn't matter if it is analog or digital, for most (and I am
> > one of those whose favor CDRs) the choice is electromagnetic storage and
> > that is likely to be problematic over time. At least with
> digital storage,
> > refreshing and transferring need not be done in real time.
> >
> > I also wonder about the implications of the recently postulated
> notion of
> > the theoretical limits of information storage and information theory and
> our
> > exponential growth of information.
> >
> > Karl (wondering how much of his work will still be around after he is
> > gone-and at the age of 56, that is likely to be only 30 years or so)
> >