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Ed Richards
6-Nov-2006, 21:16
I have noticed some finger prints on Tmax 100 negatives. These are 4x5 and the prints are toward the notched end, which is more exposed to prints. I do not presoak, since Kodak recommends against it with Xtol, but I wonder if that would help remove prints.

C. D. Keth
6-Nov-2006, 23:17
I doubt it. On films that are hard already fingerprints are most likely caused more by the oils from your skin affecting development than by actually imprinting the gelatin. It's worth a try, I guess, if you're having problems. I'd suggest just practicing handling film a bit cleaner.

Ed Richards
7-Nov-2006, 07:24
> I'd suggest just practicing handling film a bit cleaner.

Easier said than done.:-) It only happens to a few sheets, and I bet they are the sheets that slip from my fingers and have to be hunted down in the dark. Otherwise I stay on the edges of the sheets. I am concerned that gloves will shed and be more of a problem, unless someone knows of a thin glove that is really lint proof.

David A. Goldfarb
7-Nov-2006, 07:55
I found from my trip this summer, where I was away for two months shooting and boxing film for later processing (from which I still have a few batches left to process), that in this situation fingerprints are more of a problem, because the oil sits on the film longer before processing. I was shooting Efke PL100, J&C Classic 400, old TXT and new TXP all in 4x5", and the Kodak films were no more resistant to this problem than the East European films.

So now I'm loading with white cotton gloves. So far lint doesn't seem to be a big issue, but I haven't been following this practice long enough to make any conclusive judgment. I may try unpowdered surgical gloves, which would have no lint problem.

Another thing to be careful about is handling film when developing multiple batches. I've gotten the occasional fingerprint from having fixer residue on my hands when loading the next batch.

Bruce Watson
7-Nov-2006, 08:10
I have noticed some finger prints on Tmax 100 negatives. These are 4x5 and the prints are toward the notched end, which is more exposed to prints. I do not presoak, since Kodak recommends against it with Xtol, but I wonder if that would help remove prints.

Fingerprints are certainly a problem. First thing to determine is when the fingerprints were applied. If you can figure that out, you might be able to correct the problem more easily.

What I've learned to do is always wash my hands with soap to make sure my fingers are as oil free as possible before handling film. If in loaded holders I accidentally touch the emulsion, I toss that sheet on the floor and get another. It's just not worth the risk.

If I accidentally touch the emulsion when unloading exposed film, all I can do is continue processing and hope for the best. To my knowledge there's nothing you can do to remove fingerprints from the emulsion before processing that won't destroy the emulsion itself. Basically you have to scrub with a soap of some kind to dissolve and remove the oils of the fingerprint. This isn't good for the emulsion as you might imagine.

IOW, all I know to do is keep my hands really clean (don't scratch that itch no matter how bad it might be), work carefully and methodically in the dark, and reject unexposed sheets if there is any question at all about fingerprints, dirt, or scratches.

Ron Marshall
7-Nov-2006, 08:23
I do the same as Bruce, wash my hands well, immediately before loading. I occasionally will touch a sheet but so far so good.

Jim Jones
7-Nov-2006, 08:34
When using cotton gloves while loading film, one can always vacuum or blow out the holder after the film is in place to eliminate lint where it hurts.

cyrus
7-Nov-2006, 08:37
I use cheap disposable plastic gloves used in the food industry that come in bulk for anything that needs to be fingerprint free.

Ed Richards
7-Nov-2006, 08:47
Thanks Cyrus - I usually think of the surgical gloves, but they are mostly powered or lotioned. The cheap clear poly gloves for food would be perfect. I am in a hot, humid climate and use a changing bag, so keeping my hands really dry is nearly impossible.

Alan Rabe
7-Nov-2006, 09:07
There is a product in the First Aid aisle of most drug stores know as "Finger Cots". They are little latex gloves for just the finder rolled up like condoms. I roll one on my thumb and my first two fingers. They are cheap and can be reused over and over. They also fit tightly on the finger so you can pick things up and handle them. Their real use is to cover bandages on fingers. I've been using them for several years with nary a fingerprint.

j.e.simmons
7-Nov-2006, 09:17
I was given some equipment from an old hospital darkroom - included were some nylon exam gloves of a type I've never seem before. They are nylon mesh material, so that they breathe a little, but are much thicker than rubber gloves. I'm using a pair of them for loading film, and after getting used to the change in feel, they seem to work just fine.
juan

Patrik Roseen
7-Nov-2006, 16:43
To minimize the risk of putting fingerprints on the film I always put the pile of film from the filmbox with the emulsion facing down. This means that when trying to locate the pile in the dark (or in the filmchanging bag) I only touch the back of the sheet, should I accidently put any finger on them.

keeds
14-Jul-2008, 07:46
Interestingly, I've never had a problem with Ilford or Fomapan sheet film. I've been shooting some Era to get the hang of 7x17 and I've suffered badly with fingerprints this time. Will get some finger cots and use them from now on.....

Frank Petronio
14-Jul-2008, 08:45
I just wash and dry my hands. And I figure the 1/4 inch perimeter of the film is a lost cause. If I smoosh the center I toss the sheet.

Pete Watkins
14-Jul-2008, 09:41
I always wear disposable vinyl gloves when handling film and chemicals. The gloves make loading and unloading filmholders easier as well as minimising finger prints. I also had a little incident with selinium toner years ago, it really is nasty stuff!
Pete.

Ed Richards
14-Jul-2008, 09:47
Since I started this thread about 18 months ago, here is my update:

Presoaking does not help with fingerprints, but it sure helps with making skys uniform for me.

Plastic medical gloves solved the fingerprint problem.

Daniel_Buck
14-Jul-2008, 10:25
Ed, thanks for updating this thread! How easy was it to work with the negatives when you had gloves on? I'm usually shooting in California or Arizona (usually fairly dry) but I go back to Louisiana every Christmas, back to the humidity! I've thought about bringing some of my large format gear there to do some shooting, but the humidity has been a concern of mine. How do you like working with the gloves? Can you still feel the film good enough?

David A. Goldfarb
14-Jul-2008, 11:56
Since I last posted in this thread I've moved from loading with cotton gloves to loading with the same nitrile powderless gloves I use for processing film. Since they don't get wet when I load film, I can use them again afterward.

Ed Richards
14-Jul-2008, 13:11
Daniel,

I have no problem at all loading and unloading film with gloves on. I think the plastic (get them by 100 from CVS) gloves would be easier than cotton because they have some grip.

Worrying about humidty over Christmas in LA? Boy, are you spoiled. Come on down in July and August when photographers shoot.:-)

SAShruby
14-Jul-2008, 14:07
I use cheap disposable plastic gloves used in the food industry that come in bulk for anything that needs to be fingerprint free.

;)