Film-Tech Forum ARCHIVE: hypothetical: Neg-Guard?

This is topic hypothetical: Neg-Guard? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Matt Hale (Member # 1518) on 08-01-2003, 06:51 PM:

Due to a handling error, one reel of original camera negative for a film I am currently involved with (technically, only the A-roll portion of the reel) got very dirty and rather scratched in places. Fortunately through a combination of meticulous hand-cleaning and wet-gate transfer our lab has salvaged the image, and the individual responsible is paying the sizeable bill. However, all this got me thinking. Since Film-Guard is so good with dirt and scratches on prints, is there any reason it wouldn't work on a negative? Has anyone tried this? Just a thought.

Posted by Darryl Spicer (Member # 711) on 08-01-2003, 07:19 PM:

so I guess that blind transfer from the film magazine to the sealed can didn't go over to well.

Posted by Brad Miller (Member # 2) on 08-01-2003, 07:55 PM:

It would work similar, but depending on how the lab handled the printing, it may or may not be a good idea. It would really depend on the lab and such a decision should be their call.

Posted by Matt Hale (Member # 1518) on 08-01-2003, 08:00 PM:

I don't actually know the details of the incident. All I know is the print of that reel for our mix was delayed considerably while they cleaned it up. When I finally saw it, there was nothing significantly worse than the other reels so either the cleaner did an amazing job or it wasn't that bad to begin with. It just got me wondering...

Posted by John Pytlak (Member # 331) on 08-01-2003, 09:19 PM:

For optically printing or telecine transfer of the negative, a refractive index matching treatment like FilmGuard would likely help hide scratches. But in contact printing, any non-volatile material that got on the raw stock would likely have an adverse photographic effect. Long term effects on negative films would need to be independently tested using accelerated Arrhenius testing, perhaps by the RIT Image Permanence Institute.

Posted by Gordon McLeod (Member # 33) on 08-01-2003, 09:53 PM:

most labs photoguard the negative after deep cleaning it first to fill in scratchs
The Smitzer Wetgate printer also would be the choice to strike the dupe neg on

Posted by John Pytlak (Member # 331) on 08-01-2003, 10:38 PM:

Gordon is correct that the method usually used to eliminate scratches during printing is wet gate printing, either total immersion contact or liquid gate optical. The diffuse illumination (designed and built by Kodak) of the Thompson Spirit DataCine is very forgiving of scratches and surface abrasions, such that a wet gate transfer to video/digital-intermediate is often not required.

In a wet gate, the index-matching solvent evaporates completely (no residue), and the film is dried before it is wound up.

http://www.kodak.com/US/en/motion/support/h1/printingP.shtml#wetgate

http://www.rtico.com/bhp/

http://www.mandy.com/1/class3.cfm?id=9395&ar=