PMK: is an after-fix bath in used developer needed if alkaline fix is used? : LUSENET : B&W Photo - Film & Processing : One Thread

I'm going to begin testing with PMK developer in earnest over the next few weeks. I've never used it before, although I have a lot of b&w darkroom experience.

I know that Gordon Hutchings, the inventor of the formula for PMK, recommends a bath in the used developer after fixing and before washing, in order to intensify the pyro stain.

I'm going to be using Photographer's Formulary's alkaline fixer (TF-4 if I'm not mistaken). Hutchings' advice is based on use of a standard acid fixer.

Those of you who have used PMK, do you find the developer staining bath to be necessary? Does it provide any tangible benefit if an all-alkaline chemical sequence is being used?

I'm going to be testing it with Ilford Delta 100 & 400 (my standard films), plus I bought some FP4+, HP5+, Kodak Tri-X and Plus-X to see if I like traditional emulsions with this developer better (this is not relevant to the question but if you have specific advice about these films, I'm all ears).



-- Jim MacKenzie (, June 25, 2000


If you check page 19 of Hutchins book you will find that he uses Kodak's F-24. I find that with Tri-X I get a superior image to HP5+, since HP5+ has mostly chromegenic dyes and you will see no base relief image after development in a pyro developer. (Like on the back of a Kodachrome 25 slide.) HP4, although slower is IMO better also. But my preference is for slower films and Pyro developers. I use straight hypo myself, one pound to one gallon of distilled water. No rinse, no hypo clear, one hr. water wash, no hardener, since the pyro tends to harden the emulsion anyway. Pat

-- pat krentz (, June 25, 2000.

After using PMK Pyro now for several weeks, my preliminary conclusions are that both Ilford Delta 100 and Pan F+ seem to respond extremely well. TMax100 much less so ; I think that Rodinal 1:50 is a better bet than PMK for this film. Delta 100 in PMK and TMax 100 in Rodinal 1:50 seem to me to give very similar end results - exceptionally sharp, quite dense negatives, with a long tonal scale.

I have given up using an acetic acid stop bath with PMK, and simply rinse in water for about 1 minute, as I suspect that the stop bath did cause some pinholes. I then fix in Ilford Hypam, and so far have always reimmersed the film in the used developer. I might stop doing this with Pan F+, as the normal development seems to induce a deep stain anyway.

I would be interested in your results with Plus-X and Tri-X. Overall, I have found Mr Hutching's times and film speeds to be about right for "N" development, but some way off for +/-, particularly when combined with long exposure times.

-- fw (, June 25, 2000.

I have always dunked the film back in the PMK after fixing in TF4. I did read (another time, in this forum) of someone who skipped that last step and found no difference in stain intensity. One of these days I'll test for myself.

-- Don Karon (, June 25, 2000.

Using a plain water stop and TF-4 fixer will result in a properly stained negative, so, strictly speaking, you don't have to use a pyro after-bath. But....I have found that a 2-3 minute afterbath in the used developer greatly reduces the residual sensitizing dye in the emulsion (pink in T-Max, purple in Delta.) It only takes a couple of minutes and can't hurt, so why not?

-- Michael D Fraser (, June 25, 2000.

I developed my first films in PMK on Monday. I developed two rolls of Tri-X (135-36), for 14 minutes @ 21 degrees, 1:2:100. Negative densities are denser than expected - they look marvelous, but I understood they were supposed to look thin. The greenish stain is plainly evident. I'm shooting some FP4+ and Plus-X in the next little while to try them next, since they have the same development time recommended (although the EI differs, 125 for the former and 80 for the latter).

I used a 60-second running water stop, five minute fix in Photographer's Formulary TF-4 alkaline fixer (1:3), straight into the used developer for two minutes, and a fifteen-minute wash in running water.

-- Jim MacKenzie (, July 05, 2000.

Jim, use EI:80 for FP-4. Develop for 13 minutes @68F (11 3/4 @70F.) Continuous agitation for the first 30 seconds, 5 sec every 30 seconds. Use distilled water to mix your working solution (this is more important than most people know, especially with pyro.) If your meter and thermometer/timer are accurate, you will have 'perfect' negatives.

-- Michael D Fraser (, July 05, 2000.

Here's one of my images that I developed in PMK Pyro. I used Tri-X @ ISO 400, developed for 14:00 @ 21 degrees. I was pleased.

-- Jim MacKenzie (, August 17, 2000.

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