Residue on negatives

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I have a particularly persistent problem with B&W sheet film that I process. After hypo clearing, I wash in water for 15 minutes in water that has gone through an in-line filter. Then I soak and slightly agitate in Wal-Mart distilled water with 2 drops of photo-flo, forma-flo or LPN solution. I then hang dry in my dark room without squeegeeing. The film has drying marks similar to what you would see on a plate that dried in the sun, also sometimes I see fingerprints that got there when I was loading the film. I am not sure how to get rid of this residue. It shows up as streaks in the sky and blank areas of the print. I have tried varying the soaking time and the amount of photo-flo, but it does not seem to make a difference. I am also not sure whether I can load film with gloves on, I hear it is very difficult. Any suggestions are greatly appreciated.

-- Andrew Held (Heldarc@hotmail.com), December 13, 2001

Answers

Between LPN and Photo-Flo, I think LPN works MUCH better. I am not familiar with the other product. I have found that LPN in distilled water can work fine at much less concentration than indicated in the tiny print on the bottle. (Does it say 2 drops per pint?) I use 1 drop per quart and it still does the job. And don't forget that the solids in the water on the negatives when you put them in the solution tend to build up in it. I suggest a greater dilution. You can pour some of the solution over the face and back of the negative to make sure you don't get bubbles or waves of solution. There will still be very faint lines that dry on the negative, but they are small enough that with a cold light they don't show.

-- Kevin Crisp (KRCrisp@aol.com), December 13, 2001.

Andrew: I use a bit more photoflo with plain ol' tap water and dont have a problem. You might try wiping the negs gently before hanging them up. A cotton ball dipped in photoflo and squeezed out a little makes a good wipe for sheet film. Don't get heavy handed and you will not scratch the negs...just wipe the droplets off. The purpose of photoflo is to break the surface tension of the water so it runs off evenly. I just don't think two drops are enough.

Regards,

-- Doug Paramore (Dougmary@alaweb.com), December 13, 2001.


Andrew, regarding drying marks: toss your developer, stop, fixer, etc. and remake ALL solutions with your Wal-Mart distilled water. That in-line filter you are using is not fine enough to filter out the disolved calcium deposits in your tap water which undoubtedly are causing your drying marks. Do ALL your water rinses with distilled tap too. You will instantly find that your negatives will actually sparkle, and you will feel worthy again :>)

Re: fingerprints, wash hands really well to remove oils, don't touch emulsion when possible.

-- Andre Noble (andrenoble@yahoo.com), December 13, 2001.


....distilled water too (not distilled tap too)

-- Andre Noble (andrenoble@yahoo.com), December 13, 2001.

Some solvent developers will do this due to the alkalai used. What developer are you using? Some might need different stop baths and fixers.

-- George Huczek (ghuczek@sk.sympatico.ca), December 14, 2001.


I think Kevin was referring to LFN, Edwal's low foam wetting agent. I agree that it is far superior to Photo-flo. I use only 2 drops in a liter of water and haven't had drying marks on my film in a long time. A small bottle lasts for years.

-- Ed Buffaloe (edb@unblinkingeye.com), December 14, 2001.

I agree with Ed, LFN is the best. And please don't shop at Wal-Mart anymore. Support downtown businesses, not sprawl.

-- Sandy Sorlien (sand44@mindspring.com), December 14, 2001.

Ed is right, I meant LFN, I just blindly copied what you had in the question. I assume you meant LFN.

-- Kevin Crisp (KRCrisp@aol.com), December 14, 2001.

Thank you all for your thoughtful answers. I will try them and report back my results on the thread.

-- Andrew Held (Heldarc@hotmail.com), December 14, 2001.

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