fingerprints on undeveloped negatives?

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I just finished developing several rolls of black & white film for the first time, with a lot of help from information off this forum (thanks a bunch everyone!). However, I was wondering if there were any adverse effects of getting fingerprints all over the undeveloped film in the changing bag during loading onto the reels. I'm guessing that any oils are washed off during developing, and I can't see any evidence on the finished negatives, but I thought I would ask.

-- Scott Flathouse (scott@pan-tex.net), February 15, 2000

Answers

Wash and dry your hands very well before you load, and you should be fine, as long as you are not a sweaty MacDonald's grease-producing factory. And try to hold the negs by the edges; when handling them, as may be inevitable during certain stages of loading, apply as little pressure as possible and they should be fine (I've never found a need to 'sandwich' my negs between finger-and-thumb).

That said, you should be fine. It's fingerprints after they're processed which drives me nuts, and with 67, this really seems to cause problems...be extra careful after they're processed.

-- shawn gibson (SeeInsideForever@yahoo.com), February 15, 2000.


I wonder if the grease is indeed washed away. Some of it may be hydrolysed through the alkalinity of the developer, but I would think that it will at least leave a mark, if the fingerprint is on the emulsion side. It's grease, and grease repels water. Make a fingerprint in a glass and pour in some developer for a while. Then empty the glass and see if the print is gone. I guess it will at least delay the action of the water-based developer until it has been hydrolysed.

I don't think there is much to worry at this stage about finger prints on the back of the film.

If you find it necessary to "sandwich" the film between finger and thumb (as Shawn so neatly put it) there might be something wrong with your tank/reels, or at least with your technique. The film should be eased into the reels, being guided at the edges. Avoid holding the film too tight as sharp bends may lead to blackening of the emulsion and to opaque spots in the film base.

-- Thomas Wollstein (thomas_wollstein@web.de), February 15, 2000.


Thanks for the responses. I tried to be careful, and with 35mm it's not such a big deal. But with 120, I was having a bit of a hard time unrolling it without touching the film. And I guess I'll have to postpone the Big Mac & fries until post-development...

-- Scott Flathouse (scott@pan-tex.net), February 15, 2000.

Not to be too obvious here but most film supply houses sell cheap white cotton gloves, no fingerprints ever.

-- bill zelinski (willy226@yahoo.com), February 15, 2000.

No fingerprints with the cotton gloves, but not much feeling for what you are doing, either. I use them when mounting glossy prints, but to get film spooled into the reels?

-- Thomas Wollstein (thomas_wollstein@web.de), February 16, 2000.


Sure, the gloves are fairly thin (don't try this with mittens) and it works for me.

-- bill zelinski (willy226@yahoo.com), February 16, 2000.

Scott..I've developed thousands (really) of rolls of 35mm film and more recently hundreds of rolls of 120/220, all on Paterson reels, with never a finger print UNTIL I get nosey and start peeking at wet negs. JUST A HUGE HINT: if your using Paterson reels with 35mm film...leave the film leader out of the cartridge or pull it out 3 inches using a Kodak Leader retriever. With the lights ON you can thread the extended leader into the slots of the Paterson reel, over the tiny ball bearings that grip the sprocket holes. Once both edges of the film are gripped by the bearings turn off the lights. Then pull 18 inches or so of film out of the cartridge and ratchet it onto the reel. Repeat until all the film is on the reel. Cut the film allowing the cartridge to drop away. The only things that can go wrong with this technique are 1) Allowing the film to jump out of the reels starter slots because you didn't hold your thumbs over them as you ratchet. 2) Jerking the film out of a dirty cartridges felt light trap (because this method is so easy that you wanted to see if you could ratchet the film on in 5 seconds, I takes me 30 seconds or so). Anyone who has used the Paterson reels quickly learns to hold their thumbs over those starter slot tabs. And all you have to do in the second scene is keep the cassettes clean and in there cans. If they get dirty once the light is out pry off the end of the cartridge and slip the film that is already attached to the reel out of the cartridge. All this is all very easy to do. I could have probably threaded 20 rolls onto reels, with a 100 percent success rate, in the time it took me to write this...jim

-- Jim Vanson (primary_colors@hotmail.com), February 16, 2000.

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