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[PMK Question] Speaking Of Fiddling Around With Developer Variations

chuckroast

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Some years ago there was an exchange here (I think?) on cranking up PMK by decreasing the dilution from the usual 1+2+100 to 1.5+3 +100 if memory serves, though I think that 1.25+2.5+100 was also mentioned.

Has anyone actually done this, and if so, can you share the outcomes or ... is this just a dumb idea?
 
I recommend trying it (you’re not going to find any objective/quality information). It might not make much of a difference if you adjust the development time to get the same gradient. It is possible increasing the concentration of the developing agents could reduce imagewise stain and/or purported edge effects, but in the end you have to find out empirically.
 
So, my default process for developing in-camera negatives for salt/kallitype printing is to develop the negs in double strength PMK. IE: I use it 2:4:100 and it produces ideal negs for these alt processes.
After gaining a couple years experience with this technique, I experimented with boosting flatter images by using a PMK dilution of more like 1.5 to 3 to 100 and obtained very nice negatives. It wouldn't be suitable for situations where there was a full range of values, but for low contrast scenes that benefit from a bit of a kick, it works beautifully. Experiment to find your own happy place, of course.
 

At 1.5+3+100 how much did you have to adjust the development time (shorter, I assume) and EI?
 
chuckroast said:
At 1.5+3+100 how much did you have to adjust the development time (shorter, I assume) and EI?
Click to expand...

I shortened the time by maybe a minute.

I typically expose at least 2 sheets of everything I photograph, often as many as four, varying exposure or aperture a bit as I go. This gives me "wiggle room" when developing the negatives; if I find one to be a bit thin or lacking contrast, then I have the option to make a stronger working solution of PMK. In that scenario, I may not adjust the development time at all.
If I were planning to boost contrast for a scene at the time of exposing the negative, I might adjust the EI if I knew I was going to use a stronger working solution of PMK, but that's not typically how I work.

However, when I am making negatives specifically for salt or kallitype printing, I know at the moment of exposing the negative how I will be processing it, and adjust the EI accordingly. For a good salt negative, I expose FP4+ at exactly 125 ASA and develop in PMK 2:4:100 for 11-12 minutes, and that gives me an ideal negative 98% of the time.
 

And that negative would presumably be far too contrasty for silver paper?
 
chuckroast said:
And that negative would presumably be far too contrasty for silver paper?
Click to expand...

Absolutely, yes! Twelve minutes in double strength PMK (at 72F) gives a negative totally unsuitable for developing out papers. The process I described is only for alt process printing techniques.Thats quite different from upping the amount of A and B a little bit and adjusting the time down maybe 15-20%.
 

Interesting. Thanks for the responses.
 
Some films require dilutions of 2+4+100 (1+2+50) and in some instances increase of developing temperature or both to achieve decent results.
 
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