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» Film-Tech Forum   » Operations   » Film Handlers' Forum   » Cleaning 35mm films from scratches

   
Author Topic: Cleaning 35mm films from scratches
Sergio Ocampo
Film Handler

Posts: 4
From: La Unión, Chile
Registered: Feb 2017


 - posted 02-21-2017 12:40 PM      Profile for Sergio Ocampo   Email Sergio Ocampo   Send New Private Message       Edit/Delete Post 
Hi. I have a LOT of 35mm B&W films to scan and only a Nikon CoolScan 4000 ED film scanner to do it. The thing is, lots of them have scratches and I need to figure out the way to clean them out as much as possible. I tried with glycerin once and it turned out good in terms of quality but the two rollers that flatten the film between them ended up spreading the glycerin all over the film as it was liquid glycerin. So I'm looking for a way to clean the film from scratches that will leave something like a dry coat that won't spread when being pressed by the rollers and won't affect the film long-term, because I need to preserve them. I tried with liquid vaseline too and it was good in quality and it didn't spread, but I read somewhere that it is bad to clean them with vaseline for its adherent capabilities that can mess up the film in the long run.
I hope I made sense as English is not my mother tongue. I'll stay tuned for any reply! [Big Grin]

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Bill Brandenstein
Master Film Handler

Posts: 300
From: Santa Clarita, CA
Registered: Jul 2013


 - posted 02-21-2017 02:59 PM      Profile for Bill Brandenstein   Email Bill Brandenstein   Send New Private Message       Edit/Delete Post 
The host of this forum has the ideal solution (pun intended).

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Sergio Ocampo
Film Handler

Posts: 4
From: La Unión, Chile
Registered: Feb 2017


 - posted 02-22-2017 06:52 AM      Profile for Sergio Ocampo   Email Sergio Ocampo   Send New Private Message       Edit/Delete Post 
Hi Bill, thanks for replying. I was thinking of purchasing the FilmGuard, but I was told it is supposed to stay wet on the film so it can cover the scratches, so I'm thinking the same thing that happened with the glycerin will happen with the FilmGuard too [Frown]

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Leo Enticknap
Film God

Posts: 6596
From: Loma Linda, CA
Registered: Jul 2000


 - posted 02-22-2017 10:02 AM      Profile for Leo Enticknap   Author's Homepage   Email Leo Enticknap   Send New Private Message       Edit/Delete Post 
Scratches cannot be "cleaned" in the sense of removed completely. If what you are trying to do is to scan 35mm still images in such a way as to render scratches invisible, then basically you have three non-digital options.

1 - Rewash the film in order to swell the emulsion enough to "heal" light emulsion scratches. If you put the processed roll into a developing tank and then immerse it in distilled water, agitating it gently every now and again for a few minutes, and then hang it up to dry, you may find that this helps them a little.

2. Professional film restoration labs can address scratches on the base side of nitrate and acetate film by polishing it on a rotating, polished glass wheel (this doesn't work for polyester, because it's too thin and too tough). I know of no commercially available setup for doing this to consumer, stills 35mm, though.

3. Use a non-volatile, wet cleaner such as Filmguard (easily the best of all the options of this type on the market, IMHO) to fill in the scratches. The liquid has an almost identical refractive index to the film base itself, thereby reducing the visibility of the scratch in scanning or projection. What you're doing with this is essentially a cheaper and easier way of achieving the same result as wet gate printing.

If 3 is not an option for you because it may cause damage or malfunction to the scanner, then the best option I can see is to Photoshop the scratches out of each frame after scanning. It's time consuming and involves a learning curve, though.

The only dry coat scratch filler I know of is 3M Photogard (formerly known as Scotchgard), but it shrinks and goes yellow and brittle over time. Professional film restorers have had nightmares in situations where a Scotchgarded element is the only surviving one.

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Sergio Ocampo
Film Handler

Posts: 4
From: La Unión, Chile
Registered: Feb 2017


 - posted 02-22-2017 12:47 PM      Profile for Sergio Ocampo   Email Sergio Ocampo   Send New Private Message       Edit/Delete Post 
Hi Leo, thanks for this useful information. It seems option 1 is my best chance: Option 2 won't help me because almost all of the films I have are polyester. Photoshop is very useful and I've removed scratches before but this time I have 420.000+ negatives to scan so it will take literally forever. Option 1 is still tedious but I think it's more doable than the others. FilmGuard is a great option but it will only work if the liquid has a similar consistency as vaseline. When I tried the liquid vaseline, the results were pretty good and the scanner did not make a mess with it. I applied the vaseline in both the emulsion and the base. Then, I rubbed the vaseline out gently with a piece of cloth so the vaseline is kept only where it was meant to be (the scratches) and not in the rest of the film. So, I'm thinking the FilmGuard would work very well if the liquid is not so-liquid and more vaseline-like, if that makes sense.

Also, it just occurred to me that, considering the vaseline worked out that well for me, I can use it just to scan, but then the film can be cleaned with a special liquid (I'm pretty sure it exists, if you know the name or any other liquid that does this please let me know) that will dissolve all the vaseline out of the film and returning it back to normal for when I archive them.

So, summarizing: Do you know if the FilmGuard consistency is similar to vaseline? I think not because for what I know, the FilmGuard dries out all by itself and in a short period of time, so I think it has to be a fairly light liquid to be able to do that. But you never know with science.
Also, what do you think about using vaseline and then cleaning it?

Thank you very much for your time. I hope I made sense. [Big Grin]

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Bill Brandenstein
Master Film Handler

Posts: 300
From: Santa Clarita, CA
Registered: Jul 2013


 - posted 02-22-2017 06:06 PM      Profile for Bill Brandenstein   Email Bill Brandenstein   Send New Private Message       Edit/Delete Post 
FilmGuard does not dry quickly, and for the heavier fraction of its components can take months to evaporate. Or at least it does when applied to film wound on a reel.

But you never have to clean it off.

Vaseline sounds like a greasy nightmare. Film cleaning solvents might dissolve it, but that's got to be nasty stuff. And it never goes away, nor evaporates.

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Mark Gulbrandsen
Film God

Posts: 15869
From: Bountiful, Utah
Registered: Jun 99


 - posted 02-22-2017 06:56 PM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
When using a film scanner scratch reduction via software and Photoshop is about the only safe way. And both are time consuming.

Mark

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Sergio Ocampo
Film Handler

Posts: 4
From: La Unión, Chile
Registered: Feb 2017


 - posted 03-01-2017 09:32 AM      Profile for Sergio Ocampo   Email Sergio Ocampo   Send New Private Message       Edit/Delete Post 
Thank you all for your replies. I'm just entering this world and I've already learnt a lot thanks to you. What I still don't have clear is if the FilmGuard has a similar consistency as vaseline.
Thank you guys!

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Leo Enticknap
Film God

Posts: 6596
From: Loma Linda, CA
Registered: Jul 2000


 - posted 03-01-2017 10:01 AM      Profile for Leo Enticknap   Author's Homepage   Email Leo Enticknap   Send New Private Message       Edit/Delete Post 
Filmguard is a liquid, that is sold in a spray bottle. Vaseline has a jelly-like consistency.

Filmguard is designed to be applied using media pad roller cleaners (e.g. Kelmar) mounted in the film path. However, it can also be applied manually using a lint-free cloth (e.g. Selvyt). The one gotcha using the latter method I've found is that if you use a cloth that is too heavily saturated, the Filmguard can weaken and dissolve the adhesive in tape splices. You should just moisten the cloth with FG, not completely saturate it. But for still photo negatives, I'm guessing that wouldn't be an issue for you.

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Victor Liorentas
Jedi Master Film Handler

Posts: 774
From: london ontario canada
Registered: May 2009


 - posted 03-01-2017 01:30 PM      Profile for Victor Liorentas   Email Victor Liorentas   Send New Private Message       Edit/Delete Post 
I have applied Film Guard to old scratched 35mm motion picture films just to temporarily hide base side scratches.
While very wet with Film Guard...the scratches are near invisible!

I guess it's like a wet gate effect. I wonder what the studios use when wet gate scanning?

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Jim Cassedy
Phenomenal Film Handler

Posts: 1510
From: San Francisco, CA
Registered: Dec 2006


 - posted 03-01-2017 04:49 PM      Profile for Jim Cassedy   Email Jim Cassedy   Send New Private Message       Edit/Delete Post 
quote: Victor Liorentas
I wonder what the studios use when wet gate scanning?
Back in the late 1980's, I worked in a film lab for awhile, and we were
using perchloroethylene in the wet-gate printers. I'm not sure if the
same stuff was used in wet gate film scanners, or if it's been replaced
by now with something less toxic, since it was really environmentally
nasty stuff, & its' fumes were quite carcinogenic if inhaled.

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Stephan Shelley
Jedi Master Film Handler

Posts: 525
From: castro valley, CA, usa
Registered: Nov 2014


 - posted 03-01-2017 07:56 PM      Profile for Stephan Shelley   Email Stephan Shelley   Send New Private Message       Edit/Delete Post 
Not sure if it was ever done to 35 prints but back in the day I have heard of 70mm prints sent to the lab to buff out base side scratches.This was with acetate prints with mag tracks.

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