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Hi Tom:

I'm based in the northeast, in Rochester, NY - so I don't have 
experience with large film holdings out west. GEH (George Eastman House) 
is also based here in Rochester. I've known several of the film curators 
and we've had discussions with them on VS. One feels that oxidation 
(rust on film reels) helps to begin VS. Also if an acetate film is 
cleaned, he feels it helps to promote VS - but this his gut feel from 
handling film for over 40 years.

It is quite common for large film collections to analyze their 
collection using AD strips and based upon finding, separate out the 
films with VS verses films without and store the films with VS apart 
from the films without. Again, there are no empirical tests - but this a 
standard amongst most film archives that can afford to do so and the 
belief is that films emitting strong acetic acid vapors can begin VS 
with other films stored in the same or nearby containers. Your comment 
below about two acetate based tapes stored together, one tape with VS 
and one without is VERY interesting. Might one have been in a plastic 
bag and one not? Were they stored in the same physical container and did 
they both share the same air?

Because Kodak was also based here - I've seen my share of Kodak acetate 
based audiotape. I concur that I've seen more Kodak acetate audiotape 
with VS than any other manufacturer. In each case though, the audiotape 
was first stored in thin protective plastic bags, then placed in 
traditional cardboard box packaging. I think this is the way it came 
from Kodak because I have seen several unused, unopened tapes. The bag 
kept the tape from breathing and the tape was not allowed to gas-off. 
This is my guess, but if the acetate based tape has shrunk and is warped 
- even brittle, you're seeing the effects of VS on the acetate tapes but 
you don't necessarily smell it because the tapes are gassing off through 
the cardboard box. The cardboard box also buffers the acid in the acetic 
acid. This is why we see far less audiotape with VS than motion picture 
film stored in airtight metal tins. My guess is, that If the same tape 
that is dry and brittle was stored in an airtight container, you would 
smell the VS as well. And keep in mind that the very beginnings you 
quite often don't smell the vinegar - the only way to measure the start 
of VS is with an AD strip which will show the onset of VS far before you 
can smell it, based upon the PH of the tape. Inversely, I've had films 
that came to me with VS - and after allowing the films to sit in the 
open air for numerous months, even if the VS tape emitted a vinegar 
smell at first, the vinegar smell is almost completely gone over time. 
You still have the same effect as aging acetate audiotape with the dry, 
brittle, cupped condition. The film curator at GEH I know best once said 
that VS is almost always the end-life of acetate based film. What 
promotes longevity and staves off VS is the storage conditions.

Kodak has known about VS for many many years. Early tins from the 1940's 
and possibly earlier have a small relief in the inside film lid that is 
disk shaped. Inside the relief was 3-4" diameter disk of thin paperboard 
with a metal mesh grill covering it to hold the paperboard in place but 
allow the chemical put on the paperboard to slowly dissipate into the 
film can. The chemical was a solution mostly containing camphor. It is 
well-documented that camphor helps to slow the beginnings of VS. I have 
used camphor to slowly re plasticize very dry and brittle motion picture 
acetate base film that had VS. Quite possibly the same could be done for 
audiotape in the same condition? I got this recipe from someone at LOC. 
You place a small amount of natural camphor, 2-3 pieces about half the 
size of a sugar cube each, in the bottom of a metal film tin. (camphor 
and be easily found at Indian grocery stores - they use camphor for 
special ceremonies) With some small wood blocks (or portions of a pencil 
- no paint on the pencil and no eraser because the camphor will eat 
paint and eraser) you suspend the film on the reel above the camphor. 
Close the lid and seal it. The camphor is dissolved into the film. It 
takes many many many months (my latest project has been almost two 
years) but the film which was once so brittle, it would easily break 
when bent, is now more pliable and depending on how much shrinkage has 
occurred. Sometimes you can work with the film enough to scan it. Again 
it would be interesting to test this with audiotape in the same condition.

My quick fix recipe for cupped and curling acetate audiotape is to 
increase the tension settings on my ATR reel to reel deck and add 
several additional guideposts on each side to keep the tape from curling 
over itself on it's way to and from the head block. It isn't pretty but 
it has worked for the few times I needed to make a transfer where the 
tape is curling so much, it would not make it from the reel to the first 
tape guide without curling over on itself.

Regards,

John Schroth

On 3/1/2015 2:43 PM, Tom Fine wrote:
> John -- one more interesting data point about vinegar and Audiotape. 
> All of the few times I've encountered is was 1/4" 1.5 mil Audiotape 
> from the early or mid 1950s. I've never encountered it in 1/2" 
> Audiotape from 1956 to about 1961, and I don't recall hearing any 
> reports of it out of the hundreds of Mercury reels remastered in the 
> 1990s. I have encountered it with Scotch 111 from the early 50s but 
> never Scotch 111 in the familiar 1960s package of white and plaid. 
> I've encountered almost always with Scotch and Audio Devices 35mm 
> magnetic film, and in every case with Kodak media. I have no idea why 
> this is. I would think cellulose is cellulose, but apparently 
> something else is going on in the case of Audiotape. There could be 
> something in the oxide or binder that staves off vinegar syndrome, but 
> then I don't know why it happens sometimes.
>
> Interesting case in point  -- the 1956 1/4" master tapes for the mono 
> Mercury "1812 Overture." Side 1, the overture and the spoken narration 
> by Deems Taylor, the master tape is a mess. It's badly edge-warped and 
> smells of vinegar. Side 2, the Capriccio Italien, the master tape is 
> in perfect condition. Both Audiotape, both made at the same time. Both 
> tapes have been treated and stored the same because they are of one 
> single album. Why has one fallen apart and the other not? Very 
> strange! Have you seen any such things with acetate media in the 
> Hollywood vaults?
>
> -- Tom Fine
>
> ----- Original Message ----- From: "John Schroth" 
> <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Sunday, March 01, 2015 1:15 PM
> Subject: Re: [ARSCLIST] Distressing data point for upcoming ARSC tape 
> playback workshop
>
>
>> This is where AMIA and ARSC can benefit from one another.
>>
>> The members of AMIA have been dealing with Vinegar Syndrome (VS) for 
>> many more years than audio people with acetate based audio tape 
>> (acetate based motion picture film has been around since the late 
>> 1920's / early 1930's). There are storage recommendations and 
>> standards for acetate based motion picture film that have been 
>> published many times and tools one can easily find to help identify 
>> even minute beginnings of VS, such as AD strips from the Image 
>> Permanence Institute at RIT: 
>> https://www.imagepermanenceinstitute.org/imaging/ad-strips
>>
>> From my humble experience, all acetate based media slowly breaks 
>> down. Without the ability for acetate based media to "gas-off" so to 
>> speak, acidic acid leaches out of the acetate base and the vapors are 
>> contained with the media. VS begins and the vapors become more and 
>> more dense. As the density increases, the acetate breaks down and VS 
>> increases logarithmically. You see this all the time with motion 
>> picture films stored on old metal reels in old metal tins that do not 
>> allow the film to breathe. The only time I have found acetate based 
>> audio tape with VS is with the same storage parameters - the reel was 
>> placed in a protective plastic bag, then in the standard cardboard 
>> box, or protective air tight plastic audio box or the reels were 
>> placed together in an air tight plastic container. The audio tape 
>> could not breathe or gas-off and VS began. From my understanding, VS 
>> breakdown can be halted (but not reversed) by using cold storage 
>> methods. Again, I am not an expert but it is my understanding that 
>> you can halt VS at storage temps just above freezing, freezing is not 
>> required.
>>
>> Motion picture film is frozen all the time. The key is how the film 
>> is prepped and packed prior. Also how the film is unpacked and 
>> re-acclimatized to the environment prior to working with the film 
>> again in standard room conditions. Although the base is the same, 
>> there is obviously a difference between acetate based motion picture 
>> film and audiotape because of the medium that is on the acetate 
>> carrier. It is possible that the binder in acetate based audiotape is 
>> less forgiving than motion picture film emulsion when frozen - but 
>> again, another good question that may have some good answers from 
>> AMIA, as these folks work with and store, a lot of full coat and mag 
>> stripe acetate based audio recordings which are surrogates to the 
>> visual motion picture film.
>>
>> Tom, I know you're relatively speaking, but I would not want someone 
>> inexperienced reading this post thinking warmer/wetter is a better 
>> storage condition for acetate based media. Warmer and wetter than 
>> freezing - yes, but the warmer and wetter the storage conditions 
>> above freezing, combined with the inability for the medium to 
>> gas-off, the better the chance for VS to begin with acetate based 
>> media. I have clients on almost a weekly basis bring in motion 
>> picture film to transfer, who thought that the home basement or below 
>> ground office storage was the best place to store their movie film. 
>> Yes, the temps are slightly cooler than the rest of the building, but 
>> RH is definitely higher in a room "below ground level". This is where 
>> I see the bulk of the VS movie film coming in - when the client has 
>> stored the film in a basement in a metal tin. I rarely get film with 
>> VS that has come from an air conditioned house or business where the 
>> film has been stored on the first or second floor. This tells me that 
>> VS is triggered more by humidity than temp.
>>
>> On the topic of sticky shed, folks from AMIA also deal with a LOT of 
>> sticky shed. I'm now baking almost as many videotapes as I do 
>> audiotapes. And the videotapes, like the audiotapes that require 
>> baking, are the professional back-coated tapes. Most often they are 
>> open reel videotape formats although I see more and more 3/4" U-Matic 
>> tapes and other older format cassette tapes that require baking. I'm 
>> not sure myself if cooler less humid storage conditions help to 
>> mitigate sticky shed. It's interesting because a client came to me 
>> three weeks ago with reel to reel tapes that he claimed were properly 
>> stored in a climate controlled vault. They were 3M/Scotch 206 
>> audiotapes. They had the typical sticky shed and required baking even 
>> with the climate controlled storage. I'm not sure what freeze drying 
>> would do to a tape, but it might be interesting to see if this might 
>> be an alternative to baking. I've talked to several companies in the 
>> past that specialize in disaster relief. Their standard practice is 
>> to freeze dry everything (in these cases it is contents from an 
>> office building or home and AV media just happened to be caught up in 
>> the mix). I'm wondering what the effects were on the media?
>>
>> For what it's worth...
>>
>> John Schroth
>>
>>
>> On 3/1/2015 11:20 AM, Tom Fine wrote:
>>> Hi Richard:
>>>
>>> I worry that below-freezing storage of acetate media may freeze-dry 
>>> it out and make it so brittle that eventually it has no plasticity. 
>>> If super-cold/super-dry storage staves off severe sticky-shed and it 
>>> can be proven to really do that over time, then I would say it's the 
>>> way to go on that quantity of polyester-backed tape prone to 
>>> sticky-shed (I've heard estimates of 25-33% of tapes in vaults; I'd 
>>> say it's probably closer to 25% given the long history of tape 
>>> recording before polyester back-coated tapes, the fact that not all 
>>> polyester back-coated tapes develop sticky-shed, and the fact that 
>>> there is no consistent data showing that "post-sticky-shed" 
>>> formulations didn't solve the problem, and tape was used for quite a 
>>> while after the problem was said to be solved).
>>>
>>> It may well be that sticky-shed tapes need to be stored in a special 
>>> way, by themselves. Much like nitrate films (maybe even in the same 
>>> vaults, because I think they both need the same storage conditions). 
>>> Everything else should probably be stored in somewhat warmer, 
>>> somewhat wetter conditions. But, we're all just speculating until 
>>> there's more reliable science on this. I do speak from decades of 
>>> experience owning and using old acetate tapes, however.
>>>
>>> -- Tom Fine
>>>
>>> ----- Original Message ----- From: "Richard L. Hess" 
>>> <[log in to unmask]>
>>> To: <[log in to unmask]>
>>> Sent: Sunday, March 01, 2015 10:58 AM
>>> Subject: Re: [ARSCLIST] Distressing data point for upcoming ARSC 
>>> tape playback workshop
>>>
>>>
>>>> Hello, Tom,
>>>>
>>>> This is a wonderful post. Without actually stating this, you 
>>>> highlight the challenge we all face by NOT having adequate 
>>>> scientific analytical backup to help direct the care and physical 
>>>> restoration of various media. Of course, after PrestoSpace found 
>>>> that the same manufacturer tape type number could apparently 
>>>> represent four different formulations over time, we learned that 
>>>> the project is daunting if it is doable at all with any accuracy in 
>>>> an affordable manner.
>>>>
>>>> I have a couple of addenda to help round out this picture. I agree 
>>>> that more work needs to be undertaken and it is getting late to do 
>>>> it. I have spoken of your concerns whenever I thought it would make 
>>>> an impact as I know this is not the first time you have 
>>>> semi-publicly stated them here on ARSCList.
>>>>
>>>> (1) I believe, at least here at Library/Archives Canada, that FILM 
>>>> is kept cool and dry but well BELOW FREEZING (of water i.e. WELL 
>>>> BELOW 0°C / 32°F. If you want an idea about how well below, my 
>>>> GUESS is -20°C / 4°F. I also believe that this level of cold does 
>>>> help stave off "vinegar syndrome."
>>>>
>>>> (2) When I had an informal meeting with the good folks at the 
>>>> Library of Congress (I think it was late June 2012), I started 
>>>> talking about the extended baking times several of us have 
>>>> independently reported and they claim that is not needed in their 
>>>> work. I confirmed that they are working with "captive" tapes from 
>>>> their vaults. I do think this is a clue that cold/dry storage is 
>>>> reducing the severity of sticky shed syndrome.
>>>>
>>>> I am blind copying a few people to make certain this information 
>>>> gets out there.
>>>>
>>>> Thanks again!
>>>>
>>>> Cheers,
>>>>
>>>> Richard
>>>>
>>>> On 2015-03-01 9:46 AM, Tom Fine ([log in to unmask]) wrote:
>>>>> I am right now working with tapes from 1959 and 1961, 3-track 1/2"
>>>>> tapes, with splices "replaced" in 1971 (according to documentation on
>>>>> the boxes) and, in the case of 4 reels, splices cleaned and/or 
>>>>> replaced
>>>>> in the early 1990s. Alas, every splice so far has needed new cleaning
>>>>> with Naptha and many of them -- even those cleaned and successfully
>>>>> played in the 1990s -- have required full replacement.
>>>>>
>>>>> The replacement splicing tape put on in the 1990s has proven mostly
>>>>> stable but there has been some ooze and stiction around some 
>>>>> splices. I
>>>>> tend to believe that is leftover ooze from non-complete cleaning 
>>>>> of the
>>>>> original splices before replacement, but it could be new ooze over 
>>>>> the
>>>>> past 20 years.
>>>>>
>>>>> Bottom line is that there seems to be no "permanent" splicing 
>>>>> tape, it
>>>>> all seems to ooze and/or dry out over time.
>>>>>
>>>>> Another distressing datapoint ... This is the second batch of late 
>>>>> 1950s
>>>>> Audiotape acetate-backed tape I'm dealing with that has become very
>>>>> brittle, like most of the plasticity has dried out of the backing. I
>>>>> suspect this is made worse by over-dry storage conditions intended to
>>>>> somehow "prevent" or "mitigate" sticky-shed in later tapes (and 
>>>>> remember
>>>>> that there is no proof that dry storage does either). I wish some
>>>>> scientists would do some chemistry on acetate tapes and come up with
>>>>> better storage recommendations. There are millions of acetate 
>>>>> tapes and
>>>>> films being stored under the same "keep it super-dry and cold" 
>>>>> mandates
>>>>> that are imposed on polyester media (and these conditions DON'T stave
>>>>> off sticky-shed and DON'T make sticky tapes play longer after 
>>>>> baking --
>>>>> all credible research and experience so far shows that ALL tapes 
>>>>> prone
>>>>> to sticky-shed go sticky on their own, that baking allows 
>>>>> playback, and
>>>>> that ALL sticky-shed tapes go back sticky a certain time length after
>>>>> baking; the only exceptions might be -- still not widely tried or 
>>>>> proven
>>>>> -- the Richardson method of chemically removing the back-coating).
>>>>>
>>>>> Incredibly, these old tapes still sound damn good on playback, and 
>>>>> are
>>>>> able to move through a tape transport correctly after the splices are
>>>>> cleaned and repaired. I don't know if this will be the case at some
>>>>> future date. Luckily, these tapes I'm working with are backed by 
>>>>> funding
>>>>> for Plangent Process high-resolution transfers and defluttering, 
>>>>> so the
>>>>> resulting digital assets will be very high quality.
>>>>>
>>>>> My recommendations, based on this experience:
>>>>>
>>>>> 1. I've now cleaned enough gooey splices with Naptha to be convinced
>>>>> that it is effective and safe for this job.Note that many hardware
>>>>> stores carry a can or two or no Naptha at all. It doesn't seem to be
>>>>> widely used by professional painters anymore.
>>>>>
>>>>> 2. It's been helpful to carefully detach the reel flanges -- while 
>>>>> the
>>>>> tape end is taped down to the adjoining layers and the reel is not
>>>>> loose-wound -- and carefully (on a flat surface) clean all visible
>>>>> splice ooze (bubbles and chunks of white goo) with Naptha. I put the
>>>>> flange back on and flip the reel over very carefully, then do the 
>>>>> same
>>>>> on the other side. Sometimes -- not always -- this mitigates stiction
>>>>> between layers around the splice, preventing even slight oxide 
>>>>> damage on
>>>>> the edges.
>>>>>
>>>>> 3. It is important to inspect the layers before and after the splice,
>>>>> and clean all residule goo off both sides of the tape.
>>>>>
>>>>> 4. Very gently deal with the splice itself. It can sometimes be 
>>>>> gently
>>>>> coaxed up intact -- this happens about 50% of the time with original
>>>>> splices on these tapes. When that happens, clean the splice edges and
>>>>> center in particular, this is where the ooze will be. When the splice
>>>>> separates, I put a good dab of Naptha on the side stuck to the
>>>>> tape-pack, cleaning especially the center of the splice. Almost 
>>>>> always,
>>>>> a gentle coax with the Q-tip with them lift the splice up so it 
>>>>> can be
>>>>> repaired. When this doesn't happen, I used a chopstick that I 
>>>>> whittled
>>>>> down to a blunt but pronounced "shovel" point. No splice points 
>>>>> mangled
>>>>> so far with this. I then clean both sides of the splice, both 
>>>>> sides of
>>>>> the tape, with a good dose of Naptha. By the way, change Q-tips
>>>>> regularly because the accumulated sticky ooze stays on the Q-Tip 
>>>>> after
>>>>> the Naptha evaporates. Then I repair the splice (use a 
>>>>> high-quality, non
>>>>> worn-out splicing block, which isn't always to acquire these days). I
>>>>> use early 2000's vintage white-colored semi-clear splicing tape. I 
>>>>> don't
>>>>> at all like this newest thicker blue-colored splicing tape (which 
>>>>> seems
>>>>> to be the only option these days). Luckily, I have a large store of
>>>>> old-style splicing tape.
>>>>>
>>>>> 5. When playback and transfer is complete, make sure to attach the 
>>>>> end
>>>>> of the reel to the adjoining tape layer (if it's stored on a hub) 
>>>>> or to
>>>>> the reel flange with NEW and EFFECTIVELY STICKY tape. An enemy of old
>>>>> tapes, especially acetate tapes, is storage under loose-wind 
>>>>> conditions.
>>>>> The acetate expands, contracts and sometimes gets vinegar 
>>>>> syndrome. If
>>>>> it is stored tight-wound with the end taped down, it is less 
>>>>> likely to
>>>>> get edge-warp.
>>>>>
>>>>> 6. Under ideal archival conditions, without tight production 
>>>>> deadlines
>>>>> and with unlimited funding, I would say replace all old splices as 
>>>>> SOP.
>>>>> Under real conditions, this is not always possible. Because of that,
>>>>> expect to go through this same procedure again if the tape is played
>>>>> again in the future. And, given my experience with 1990s splices, I'm
>>>>> not sure that modern splicing tape is any better about eventually 
>>>>> oozing
>>>>> glue or drying out.
>>>>>
>>>>> 7. This probably goes without saying, but demagnetize the tape 
>>>>> path, all
>>>>> metal tools, and work on the splice repair on a non-magentic surface.
>>>>>
>>>>> 8. It also probably goes without saying, but use Naptha in a
>>>>> well-ventilated area. John Chester turned me onto putting in a little
>>>>> squeeze-bottle with a needle tip and then squeezing a few drops 
>>>>> onto a
>>>>> Q-Tip rather than having an open container and dipping Q-Tips into 
>>>>> that.
>>>>> This method really keeps the fumes to a minimum in a normal-sized 
>>>>> room.
>>>>> I keep a low-speed fan blowing air across the tape transport to move
>>>>> what fumes do escape away from my face.
>>>>>
>>>>> -- Tom Fine
>>>>>
>>>> -- 
>>>> Richard L. Hess                   email: [log in to unmask]
>>>> Aurora, Ontario, Canada                             647 479 2800
>>>> http://www.richardhess.com/tape/contact.htm
>>>> Quality tape transfers -- even from hard-to-play tapes.
>>>>
>>>>
>>>
>>
>>
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