The Vinegar Effect

[Bill Jennings]

There seems to be a great deal of expertise on this forum about film, archiving and restoration.  So, if it is not too much trouble, I have some technical questions about the chemistry and decomposition of film stock through the "Vinegar Effect."  I've read that even the airborne presence of some of the chemicals released during the decay process can permeate nearby film cans in the vicinity and set off a kind of "chain reaction."  Is this true?  How long is it before film stock begins to succumb to the process?  Or, can the process be stalled indefinitely?  Along with that, we have seen the return of DW episodes and other materials in recent years.  What kind of decay/chemical condition were these in, and are their any trends in the overall condition of the returns thus far?   Thank you in advance for any insight you can offer!

[Mike Biggs]

Happy to be corrected on any of this, but my understanding is that the chain reaction you describe can happen. Controlled environmental conditions are key to long life with film, generally the colder the better and at suitable humidity levels - its also important that these are consistent, fluctuating levels can be very damaging. My understanding is that vinegar syndrome cannot be undone or stopped, although it can be slowed down using colder temperatures. The opposite is also true and hot and humid conditions will speed it up. There is some information online here: www.nfsa.gov.au/preservation/handbook/cold-storage-of-film/cold-storage/

How long film stock has depends on the storage conditions, age isn't the overwhelming consideration. In my family photographic collection I've got acetate negatives from the 1950s that are fine and others from the 1970s that have early vinegar syndrome. And these were all just stored in wardrobes.

Can't speak for the DW episodes though!

[shellyharman67]

I believe this is why if they have found a large amount of Who and they are in a bad state they are more likely to be urgently trying to save them than keeping us in the loop ?

[Mike Biggs]

Jan 11, 2014 6:48:34 GMT shellyharman67 said:

I believe this is why if they have found a large amount of Who and they are in a bad state they are more likely to be urgently trying to save them than keeping us in the loop ?

Possible, but doubtful (I've kinda lost heart in the omnirumour, would love it to be true though!). And if it's too advanced in it's decay, there is no way it can be recovered, there is this site which describes the different stages in a bit more detail: www.filmforever.org/chap3.html

Infected films are still recoverable at stages 1 and 2 (and only with radical treatment at stage 2), but beyond that it's considered a loss.

Of course it's always possible that new treatments might be invented to slightly improve the situation, but we're dealing with a physical degradation and you do just reach the point where there isn't anything left to save.

I should emphasis that I'm not a film conservation specialist though and this is based off presentations I've attended and people I've spoken with from national institutions. I don't necessarily keep up with changes in this field.

[Jeff Haynes]

I collected 16MM for a while. I still have some cartoons. Remember we are talking safety stock and not nitrate film. My eperience is this. I had a print of a Flintsones episode (color) and a print of The Honeymooners (B&W)both around 25 minutes each. Both were fine when I got them, both were stored right next to each other, where I was later to realize were not ideal conditions. 20 years later I still have the Flintsones print and years ago I had to junk the Honeymooners. Still though, if the print was a missing episode of something the image would have been recoverable. About 10 years ago nitite prints were discovered, I think in a garage, of a missing silent western serial. They were from the same serial, all made at the same time, all stored for decades in the same place, again not ideal conditions, 10 times worse than my film had been stored. Most of the episodes after restoration looked beautiful, a couple were goo and dust in the cans. You just don't know. WOF and EOTW were in Africa and look really good. Say really poor condition prints do turn up of the Doctor, jumpy, bubbly, scratchy, I'd rather have that than nothing. Beggers can't be choosers.

[shellyharman67]

People have to be realistic about the shear number if true ! You cant take for granted whats on the label is whats in the can ! Its gonna be a long time sort that lot out. Gotta be some who even if Dupes i would think

[Bill Jennings]

Thank you for the thoughtful replies! It would seem that the discovery of any material (even duplicates) is useful because not only because of the distribution story they tell, but also the chemical story on how film behaves in these varying environmental and storage conditions.

[scotttelfer]

The Enemy of the World and The Web of Fear were suffering the very early stages of decay, when the can was opened the smell was very distinct but when put through the various cleaning processes the smell disappeared. Of course it can't be stopped but now that they are being stored in the correct conditions they should be fine for a very long time.

[Neil Lambess]

Vinegar Syndrome can be very hit and miss , a LOT of it depends on how the original film stock was made and what degree of impurities were in the chemical batches and the acetate stock......
it can also have several causes and effects ......(which is why its called a "syndrome" its a set of problems that develop over time. not all films suffering from it show the same symptoms or degree of symptoms....
so it really is luck of the draw......
in some cases it can be made worse by the film been kept in the can.....

[shellyharman67]

Thats why if they are back they would have to quickly stabilise them fast ! Because its for sure they were not stored properly. Thats why we may of not heard any news yet, and will not for a while. Of course, thats if they have found anything