>From: PO2::"[log in to unmask]" "Folklore Discussion List" 15-DEC-1=
994
> 10:25:41.06
>To: Multiple recipients of list FOLKLORE <[log in to unmask]>
>CC:
>Subj: Re: IMPORTANT- Saving old audio tapes
>
> For the last year I have been working in the archives of the Blue
>Ridge Institute of Ferrum Virginia. Before that I worked for the Southern
>Folklife Collection, at the University of North Carolina, as a recording
>specialist. My job was to restore, to re-record and save as much of the
>large field tape collection as I could. Many of the tapes were
>recorded on Ampex 406/407 in the 1970s, all of which had developed what
>is called "sticky " tape syndrome. I wrote an article about the problem
>but could not get it published. So far I have not been able to find the
>article, however here are the main points that I hope will be of
>interest to folklorists:
>
> If you have old recording tapes of any kind, including reel to reel
>cassettes, VHS and even computer disks and tapes, that date back
>to the 70's, you are on the verge of loosing them. The U.S. Government
>now recognizes that recording tape of ANY KIND has a safe
>life of not more than 15 years. I know that some of you have tape that goe=
s
>back to the 60's of even the early 1950's that still plays. That does
>not matter, get your hands on two tape recorders and transfer your
>collection to new tape as soon as possible.
>
> Remember you cannot save ANY recording tape. All recording tape
>is going to rot. What you save is the contents of the tape by
>re-recording to another fresh tape. You will have to do it again in 10
>or 15 years. Therefore, try to use the best recording equipment that
>money can buy in order to insure a quality transfer. If you cannot afford
>good equipment use what ever you have. It is better to transfer the tape
>even on low quality equipment, than not to do it at all. Even transfer
>to cassettes if you have to. When decide on the equipment-- hook them
>together directly to transfer-- dont go through microphones.
>
> Now to "sticky" tape syndrome. If when you put your tape on the
>recorder, push play, and the tape starts to squeel and even stick to
>the heads of the recorder-- that is "sticky" tape syndrome and there is a
>very good chance that nothing can be done to save the tape. However, I
>have save many hundred of these tapes and here is how you can do it.
>
> The reason that the tape sticks is that the formulation (the plasti=
c)
>has absorbed water from the atmosphere and turned the tape itself into a
>sticky soft plastic. What is needed is to harden the tape and drive away
>the water. The way to do this is by applying heat. The easiest way is
>to use your home (elecrtric only--no gas ) kitchen oven.
>
> First go to the hardware store and purchase a thermometer that
>goes down below 100 degrees Fahrenheit. Experiment with the oven settings
>until you can control the heat. Use the thermometer, you cannot rely on
>the accuracy of the oven control knob settings. The temp. must be set to
>stay withena 140 to 145 degree range. Caution-- above 150 degrees the
>tape will melt.If you cannot control your oven don't use it find another.
>Take your tapes out of their boxes and place five of six of them
>flat on the oven racks and heat them at the above temp. for 5 hours.
>Turn the heat off at the end of this period and allow the tapes to cool
>down for 2 additional hours while remaining in the oven.
>
> Now all you have to do is transfer the tapes. Most likely the
>tape will play well.. However sometimes it may take a second treatment.
>Once you have transfered to new tape throw the old "sticky" away becaus
>it will turn sticky again within a short period of time.
>
> If you do not have an oven. You can build one by placing a 500
>watt light bulb in a 2-3 foot square cardboard box and stacking the tapes
>inside. Make sure that the light bulb does not touch the tapes or the
>boxes as it will get very hot.
>
> I take no responsibility and there are no guarentees but
>With care you should have good success-- GOOD LUCK.
>
>
>Pat Sky
Some of you may have received the above email, and as a professional
magnetic media conservator, I think it is important to point out some
problems, innacuracies, and poor recommendations in this email. In terms
of background, our company is the largest and most succesfull magnetic
media restoration company in the US having offices in New York, Los
Angeles, and San Francisco. We do work for all the broadcast networks as
well as the Library of Congress, and dozens of museums and commercial
clients.
The detioration of magnetic media is indeed a vexing issue, and needs to be
addressed by any institution having a large or important collection of
magnetic media. I have attached 2 articles to this email, one on proper
"care and feeding" of tape, and the other on issues relating to cleaning
and restoring magnetic media masters entitled "Confessions of a Videotape
Restorer or How Come All These Tapes Need To Be Cleaned Differently".
These articles have been published widely and you are free to distribute
them.
The article above indicates that all tape will "rot". This is at best
technically innacurate. Magnetic media is a layered media that consists of
a base which is usually polyester, a binder (or glue) system which is
polyurethane based, and the magnetic particles themselves which can be a
wide variety of compositions including iron oxide, Chromium Dioxide, Metal
Particle encased in ceramic, and many, many other formulations. The main
problem with tape over time is NOT the loss of magnetic properties (and
therefore the loss of content). In fact, it is extremely rare for tape to
loose enough magnetic "charge" to seriously threaten the integrity of the
recording. The main problem which is referred to as "Sticky Shed Syndrome"
appears to be a hydrolosis process over time with the polyurethane binder
systems that is used in most tapes. Because each tape type (and even
batch) are significantly different, the rate of this reaction varies
widely.
Baking tapes is only one of many techniques used to condition the tape well
enough to transfer it properly. It is by far one of the most dangerous,
and the idea of placing your masters in either a kitchen oven or a
cardboard box with an electric bulb is at best an extremely poor
recommendation. Although baking can, in some instances, temporarily
reverse the hydrolisis reaction, it also may ruin the master for all time,
and as such we consider this process as our very (and I do mean VERY) last
resort after we have tried many other techniques. We do on rare occasion
bake tapes, but we use a scientific oven accurate to very tight tollerences
with active circulating convection with digital thermometers, alarm
systems, and an automatic shutdown circuit in case of overtemperature.
Each tape is carefully inspected and cleaned other ways FIRST to minimize
other contamination problems which can and do occur. Other less precise
techniques are (if you will pardon me) a recipe for disaster.
We NEVER recommend that a client destroy a master recording even after it
has been restored to another copy. Over time there will be better
technology to deal with these problems and you can never recover as well
without the original master. Basically a restoration master can never be
as good as the original.
Although the author above is obviously well intentioned, the proper
restoration of magnetic media requires a great deal of expertise in several
areas, and should not be undertaken lightly. I hope the attached articles
are of value.
Jim Lindner
President
VidiPax
"The Magnetic Media Restoration Company"
[log in to unmask]
Toll Free Help Line
800-653-8434
-------------------------------
The Proper Care and Feeding of Videotape
by Jim Lindner
VidiPax=81
Videotape is becoming an important media in most collections. As the
investment in videotape grows over time, it becomes very important to take
good care of the videotape to safeguard your investment. Whether your
collection circulates or not, videotape has a much shorter life span than
most people know. In fact, a videotape that is over 15 years old almost
certainly needs careful attention, and most tapes over 20 years old need
professional help. If your collection consists mostly of professional
productions or films that are still in print, the least expensive
protection is usually purchasing another copy. For a locally produced,
old, or out of print videotape, proper care is the only way to guarantee
the ability to view the tape in the future.
The following recommendations for the storage and preservation of Videotape
are a combination of manufacturers recommendations, experience with old and
obsolete tapes, and good common sense.
Keep Videotape Cool and Dry... and away from curious fingers
You are better off keeping the tape in a place which has constant
temperature and humidity then in a cooler place with lots of traffic.
Tapes left for the curious to handle WILL be destroyed, it is only a matter
of time.
Give your tapes some "exercise"
Tapes need to be fast forwarded and rewound periodically. The recommended
interval for doing this process varies according to temperature and
humidity, but a good rule of thumb for normal office air conditioned
environments is every 6 months.
I do not recommend tape rewinders for this purpose. Most rewinders are
very inexpensive and subject the tape to questionable tension. Simply use
your VCR and fast forward and rewind the tape. It is a good policy never
to leave a tape stopped in the middle of the cassette. Always rewind the
tape fully.
Protect your tapes from physical damage
Cardboard sleeves and inexpensive "library" cases provide little protection
for either the cassette or the tape inside. Often these inexpensive cases
are made of materials that deteriorate over time. Protect your investment
with a high quality shipping case or "Videotape Vault". These cases are
inexpensive, reusable, and will last many years.
When in doubt, make a copy.
You cannot recover from a lost single master. If you only have one copy of
a tape, NEVER allow that copy to circulate. Copies are inexpensive to make
and are your only absolute protection against the loss of the program.
Often you can recover if you have made copies, even if the quality is
lower. Ideally keep copies in different places, and make copies at
different times so that they do not all age together.
Make sure the machine works BEFORE you insert a tape.
The biggest cause of damage to tapes is machines in bad condition. If you
are uncertain about a machines condition, insert a tape that is not
valuable to ascertain that condition. If a tape is damaged, do not insert
it into a videotape recorder, the tape may damage the machine.
Keep Videotape clean, Keep Videotape out of the light, Keep Videotape away
from strong magnetic fields.
It may seem obvious, but then again do YOU store any of your video tapes at
home on top of the TV? Dirt, humidity, and heat are the main enemies of
videotape and can make the tapes impossible to play back in very short
periods of time. A few security systems use very strong magnetic fields,
which over time can severely damage the information stored on all magnetic
media. Make sure that your tapes do not get passed through these type of
devices on a frequent basis.
If you can - know what type of machine the tape was recorded on, and keep
the machine!
It may not seem important now, but 20 years from now, it may make matters
much simpler. The practical reality is that there are many videotape
formats that become obsolete quickly. Knowledge, and ideally possession,
of the machine that recorded the tape originally can be extremely valuable.
Always label your tapes.
Unless a tape is properly labeled, the only way to know the contents is to
play the tape, and if the tape cannot be played back without restoration,
how do you know whether the contents are valuable enough to justify
restoration cost? Even a simple card system can go a long way in helping
to know the contents of a tape, long after the tape has been completed.
Know when you need professional help. Many times local expertise is simply
not qualified to deal with videotape restoration issues. Damage to a tape
that is caused by well meaning people "trying to help" may be permanent.
Become the organization expert, and know when to call for help.
--------------------------
Confessions of a Videotape Restorer: or How come these tapes all need to be
cleaned differently?
By Jim Lindner --- VidiPax=81
{This article has appeared in the current issue of the AMIA newsletter, and
is reprinted with permission}
I would like to share a few of my observations that have been gained
through restoring several hundred videotapes. These tapes have come from a
wide variety of sources and include many different formats including 1/2"
reel to reel, 2" Quad, 1" Types A, B, & C, 3/4", and many other obsolete
formats too numerous to mention (or remember). These tapes have been
stored in a wide variety of conditions, some in pristine climate controlled
vaults, and some in the top of closets in Florida or in the flooded
basements of houses along the Long Island Sound. All of these tapes had
one thing in common: (they cannot be played by the user), and, perhaps most
importantly, many things that were different.
The scant literature on videotape degeneration primarily discusses binder
breakdown or what has been termed the "sticky shed syndrome". While many
of the tapes that we have restored have exhibited this problem to various
degrees, I have come to learn that many of the tapes have compound problems
that do not fit the "classic" profile of sticky shed syndrome. In
addition, while I have heard that many are looking for a "holy grail"
solution that cures all tapes of their illnesses at least long enough to
get a decent transfer, my personal observation is that such a single cure
all is highly improbable, and that there is no one solution to the various
maladies that have come my way.
This realization is quite important because it means that the general
application of a single solution "cure" can actually make the tapes much
worse then they were before the cleaning process was applied. As an
obvious example, a tape that has a physical fold could be severely damaged
by a cleaning machine that scrapes the surface of the tape with a razor or
similar "burnishing" station. Similarly, baking a tape that does not have
sticky shed syndrome but does have serious chemical contamination due to
its sitting in contaminated water for a couple of weeks is not a good idea.
In fact, we have seen tapes that are of the same format, shot
approximately at the same time, and stored next to each other exhibit
different problems. More often, we are greeted by exasperation on the part
of the client when one of two tapes that have been stored identically does
not play when the other is fine.
A single cure solution actually seems silly when one considers some of the
differences in the design of videotape itself, the requirements of the
machines that the tapes were recorded on, and the handling the tape
received during and after production. As the technology of videotape
recording changed over the years, so too did the characteristics of
videotape, because the demands of the equipment required different
performance on the part of the tape itself. Indeed, videotape engineering
is a crucial element in recorder design because what good is a fantastic
machine without the tape to record the image on? In many cases, the design
of the recorders required radically different types of videotape
performance, and, as a result, the chemistry of these products and the
manufacturing techniques used to make them are very different. 2" Quad
videotape, for example had to withstand severe abuse from the heads every
time that it was played due to the deep head penetration that this format
required. As a result, this tape is much thicker than the tape used in
current digital videotape recorders whose heads barely touch the tape but
require a much higher recording density than quad technology. Optimal
abrasivity of the tape is also different for different formats, and the
"stiffness" of the tape which was optimal for proper head to tape contact
in one format could be very different for another format. Many other
characteristics of videotape vary significantly from format to format, and
in some cases from magnetic tape supplier to supplier.
The importance of maintaining a proper environment for tape storage has
been discussed, but some of the worst problems we have encountered are
caused in production... long before storage has occurred. What single
restoration solution could handle the unintentional abuse given by a well
intentioned crew member who placed a tape inside a sandwich bag (that
apparently previously held a sandwich) where it remained for 20 years?
Some of my personal favorites include the tape that broke in production and
was taped together.... with duct tape, and the tape that had paper
"bookmarks" to mark where an important scene started. And of course there
have been tapes that have been visited by living creatures over the years,
some microscopic, and some generally characterized as "vermin".
I have seen old quad tapes that have the problem of oxide literally flaking
off the base, but I have never seen 1/2" reel to reel tapes have a severe
shedding problem where the oxide literally separates from the base in a
large section. Similarly, I have seen 1/2" tapes that needed to be cleaned
8 times before the adhesive could be removed for playback (classic sticky
shed syndrome), but I have never seen stickiness quite this bad with quad
tapes.
Unfortunately the end result of these videotape problems may appear to be
the same... clogged heads which do not allow the video to be viewed.
Jumping to the contusion that the malady that caused the clogged heads is
the same problem for different tapes is most often incorrect, and the
theorem that one cleaning solution will work for all tapes is similarly
incorrect.
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