I feel pretty much as Scott Balko feels that I'm just wasting the time of the folks here for some of my questions when HIAC is a lot more "forgiving" of the newbie question -- that is, I'd say that many of the lurkers and users of HIAC are fairly new to 35mm, are collectors and not 35mm professionals, and are thrilled to help others using the knowledge that they had only recent gained.

But Film-Tech is great for me when I have a question that only the pro's can answer, like what's the difference between a Cat 280T and a Cat 350 card, for instance. (Thanks, Brad, for that answer )

The best way to prevent vinegar syndrome is to store the film properly. SMPTE Recommended Practice RP131 recommends cool and dry storage for long-term film storage. Low humidity storage reduces the amount of the moisture that initiates hydrolysis. Cool storage greatly reduces the rate of any chemical degradation reaction. Using vented storage (acid-free boxes or vented cans, NOT sealed cans) prevents the accumulation of acid vapors. It is good practice to inspect and "exercise" (carefully rewind or project)stored film periodically, which also helps release any buildup of acid vapors. The presence of iron (e.g., from magnetic striping or rusted film cans/reels) tends to accelerate vinegar syndrome.

Kodak developed "Molecular Sieves" which are packets of a special material that adsorb moisture and acid. Placing molecular sieves in sealed film cans adsorbs excess moisture and any acids, greatly retarding vinegar syndrome. Kodak recently won an Academy award citation for the invention of Molecular Sieves.

For more information on Molecular Sieves, see Kodak's FPC website:
http://www.fpcfilm.com/US/en/motion/FPC/fpc/mole.html

For information on the storage and preservation of motion picture film, see the Kodak web site:
http://www.kodak.com/US/en/motion/support/technical/care.shtml

For films that have already begun to deteriorate with vinegar syndrome, the molecular sieves adsorb moisture and acid, thereby reducing the level of the two things that accelerate the reaction. The amount of odor is not a reliable indicator of how much acid is present.

As the molecular sieves adsorb moisture and acid, they gain weight. The weight gain can be used as an indicator of how much they have adsorbed, and when to replace them as they become saturated. It may be that film had so much acid that the molecular sieves quickly became saturated. To find out the amount of weight gain you might expect to see with saturated molecular sieves, compare the weight of a fresh packet, and one that has been exposed to a humid environment (e.g., damp basement or steamy shower) for about a week.

Since you know your film already has vinegar syndrome, it is especially important to store it in a cool place, and periodically wind/project it to "exercise" it.

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