View Full Version : Need Help With Old Neg's

Steven Rice
6-May-2005, 12:02

My name is Steve Rice and I really need some help here. I am responsible for taking 20,000 or so old negatives from 1929-1980ís and digitizing them for my school as a summer job. I am familiar with my computer, my scanner, the software etc. but I am not familiar with how to deal with these negatives. Many of the negatives are dusty which is easily taken care of. The problem I am having is along the edges of the film there is a residue that looks like some sort of dry chemical or possibly mold. Whatever it is causes veins of faint white light to show up when scanned. I was wondering if there was any way to remove this. Are there any products I could buy to get this stuff off without damaging these historical photos?

Any feedback would be appreciated.

Steven Rice

6-May-2005, 13:43

It sounds like mold, and should probably be removed by wet processing. However, if the negatives have any serious value, they should be scanned (or better, archivally printed) as-is before risking recovery treatment. Since I suspect that they aren't going to merit this kind of investment
(and 20 ,000 negatives is a daunting number, even for a whole summer's work) you might consider Edwal No-Scratch or something similar.

Back when thin-emulsion 35mm films were a novelty, and pushed for three or four stops of extra speed, fine handling scratches and dust really showed up, especially with a condenser enlarger. This was due to scattering of the light, which is one of the things that mold does. The function of the No-Scratch was to fill in the defects with an index-matching liquid that was inert to the film and which would evaporate in a reasonable amount of time without leaving troublesome residue.

Someone more conversant with modern scanning technology can probably tell you if the index-matching liquids used for high-end scanning would do for this. If memory serves, the Edwal product could be used by simply wiping it on, lightly enough so as not to cause problems with a glass-type negative holder. Of course, if you eliminate the scattering, you may still have absorption by the mold or residue, which would lead to dark areas instead of white ones.

If you know for a fact that the negatives are going to be destroyed after scanning, then anything from Vaseline to automotive-grade silicone grease is worth a try. I probably shouldn't mention how well the skin oil from the side of your nose works in an emergency...

Gary Samson
6-May-2005, 15:05
Check the collection to make sure these negatives are all on "safety base" film. It's possible you may have some nitrate base negatives which pose a serious fire hazzard. Nitrate base negatives can spontaneously combust. If they have a distinct vingar like odor you may have nitrate negatives.


domenico Foschi
6-May-2005, 15:08
Try PEC-12. It's an archival photographic emulsion cleaner, designed for fungal growth.
The only catch is that works well with hardened emulsions, it is damaging to the unhardened ones.
I am not sure if 1929 they were using unhardened emulsions , but you can do a test.
It is produced by Photographic Solutions Inc.. 7 Granston way, Buzzrd Bay, Ma., 02532.

6-May-2005, 17:48
I googled your email....any chance this is your school?


if it is--I don't know if you've already done this--but find out if they have a conservator for the gov't records archive they list on that page. If they don't, find out who the contact is for the state archive or state library that will be handling the state gov't public records. There's going to be an archive someplace in your state, and there's a very good chance that they will a photo conservator, or at the least a paper conservator who can offer some advice....

6-May-2005, 18:01
btw--nitrate smells like musty sweatsocks. acetate, "safety base", smells like vinegar. you'll know it when you open a file cabinet or a box full of them....

I wouldn't try the old nose-grease method with them or do anything to them actually. I wouldn;t put an ungloved finger on them or rub my skin afterwards....anything before 1950 is suspect to be nitrate, unless proven otherwise. The nitrate is not only flammable, but there are health/safety type issues with nitrate negs ....

Mark Sawyer
6-May-2005, 20:42
Nitrate negs decompose to produce small amounts of nitric acid, acetate to produce acetic acid. It wouln't run the nitrates through a scanner that warms up much; although the risk of spontaneous combustion is low, it's still real. (When I was a kid, I thought "anti-inflammatories" were to prevent spontaneous human combustion...)

Most safety film was labeled as such. Some nitrate said "nitrate," but in my experience, not much of it. If you want to check, snip a little strip and ignite it outdoors. Safety film will often burn, but just barely. Nitrate burns almost like a dynamite fuse. Don't breathe the fumes, of course.

I've seen nitrates from the 1920's in beautiful shape, and both nitrates and safety film from the 1940"s-50's in horrible shape. Nitrates sort of melt to mush, safety seems to separate into layers, and both show the usual problems of bad processing in the expected ways, (staining, silver migration...)

Don't know what the white residue might be, but I'd be very cautious about wetting the negatives; the emulsion might separate from the film base. If you must, experiment with less-important pieces of film, and scan all negatives before treatment, just in case. Or live with the lines on the scans, and let someone fix them in PhotoShop as they're used.

Wish they still made nitrate film; I produce so many negatives that deserve a fiery demise...