8mm Forum: Is There Permanent Solution For Base Scratches

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Posted by Anthony Massaro (Member # 216) on March 11, 2005, 04:37 PM:

Hello:
Read the recent post with interest concerning permanent solution to emulsion scratches (warm water treatment). It reminded me of a blurb I read some years ago referring to a company which used a process to permanently [Eek!]

remove base side scratches. According to the blurb - they were very expensive but did live up to their claims. Don't remember where I read this - does anyone have any info. I only know of being able to remove scratches on a temp basis through wet gateing. Would love to be able to "save" some worn prints where some of the lines just can't be removed.
- Anthony

Posted by John Whittle (Member # 22) on March 11, 2005, 08:13 PM:

At one time there were several film treatment companies (Permafilm, Comprehensive and others) that would take release prints and apply a solvent to the base (cell) side and pass it over hard chromed polishing wheels.

This gave a distributor a little more life out of a 35mm or 16mm print for theatrical or television release. In large quantities I think we paid around $12 for a one hour show back in 1972-73. It was about a 20 percent of what a new print would cost in 16mm.

Most if not all these companies are now gone and in the passing years we noticed that prints that were so treated are more likely to fall prey to VS. Perhaps the treatment started a breakdown of the chemical structure of the cell but at this point no one with money is interested in understanding the problem so it's left with collectors.

Now days preprint material for telecine or printing is printed with a liquid gate that fills the defects with a liquid that has the same optical diffraction as the film base and thus the blemish is hidden. Again these solutions (like film cleaner) are not friendly and are circulated, fume captured, and controlled under strict regulations. Some of the chemicals are now on the endanged chemical list! (One popular one is the same one used for dry cleaning and it's that fact alone that's kept it available since dry cleaners have a larger lobby than film labs).

There were also other treatments for release prints that was supposed to make them wear longer. Vacuumate was one treatment for reducing moisture in the emulsion and 3M had a treatment you applied on an expensive machine to the base that was cured with UV light that was to help make it wear longer.

And in the early days, Kodak used to lacquer Kodachrome film and you could removed the lacquer with thinner and re-lacquer the print.

But to answer your question, I don't there there is a "permanent" solution available anymore.

John

Posted by Jan Bister (Member # 332) on March 12, 2005, 07:55 AM:

Unless one were to have a new print made from an existing one while filling in the scratches on the original film through wet gating... (right?)

Posted by Kevin Faulkner (Member # 6) on March 12, 2005, 09:07 AM:

Hi John, I suspect that these treatment actually sealed the film which then stopped it from being able to breathe. Many people over the years have said that VS is nore likely on old film stored in cans and again the film base cant breathe. I dont think its the treatments chemicals that causes the breakdown.
Maybe the only treatment these days is a silicon based lube which would hopefully fill the scratches up but of course this is only semi permanment.

Kev.

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