I've been processing black and white sheet film (4x5, 5x7 & 8x10) in trays for some time now, and I thought I had the method for producing scratch free negatives... until I recently developed my first batch of 4x5 Kodak High Speed Infrared (Type 4143, I believe). This has got to be the softest film emulsion ever produced, as my fingerprints even lifted the emulsion from some spots. I have several questions:

1. Does anyone else have experience with this problem?

2. Short of tank processing, do you have any suggestions?

3. I always presoak my film; should this film be an exception?

Any thoughts are appreciated.

-- Chad Jarvis (cjarvis@nas.edu), July 20, 1999

Answers

> 1. Does anyone else have experience with this problem?

Yes -- the thinner film base doesn't help either!

> 2. Short of tank processing, do you have any suggestions?

Thin rubber gloves and one sheet at a time in 5x7 trays. I gave up and got a Jobo sheet film tank which I use for inversion processing.

-- John Lehman (ffjal@uaf.edu), July 21, 1999.

The problem lies not in the processing but in loading the film. You have to use either the latex/nitrile gloves or the lintless cotton gloves when handling the film when loading. I'm told by an old, old photographer that the oil in your skin absorbs light. I use cotton gloves to handle the film before loading and have no problems and use my bare hands to unload and process the film after exposure and have no problems. I use the dip and dunk method to process which works fine for me. Nice smooth tonalities with no motteling from agitation. James

-- james (james_mickelson@hotmail.com), July 22, 1999.

I tank process and don't presoak this film. I handle it bare-handed (carefully), and haven't encountered a fingerprint issue, etc. I do have agitation problems with this film (only).

I'm switching to trays for this film, and I'm going to hunt around for 5x7 trays or big soap dishes and do one sheet at a time. That's my suggestion. Presoaking shouldn't hurt you, but it's an additional bath to handle it in... and I'll probably start without it.

-- John O'Connell (oconnell@siam.org), July 22, 1999.