More Questions On Pyrocat

thronobulax

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Having now had time to explore Pyrocat-HD in a variety of ways (N, N-1, N+1, Semistand, Stand) I beg the group's indulgence as I once again make myself a pest.

Keep in mind that I write this in the context of having developed LOT of film in D-76, DK-50, HC-110 Dil. B, and PMK Pyro. In all cases, we're talking about open tank hanger processing. My initial foray with Pyrocat-HD has been almost entirely with Agfapan APX 100.

Observations:

  1. Claim: Pyrocat-HD gives you less visible grain. Agree, it is like PMK in that regard.

  2. Claim: Pyrocat-HDis less fussy about agitation and oxidative effects than PMK. Agree.

  3. Claim: Pyrocat-HD gives you nice edge effects. Unclear. It's not evident with APX 100. Even the few Tri-X sheets I did semi-stand did not show this, certainly not by comparison to what I get with PMK.

  4. Claim: Pyrocat-HD gives you better film speed than PMK. A qualified "maybe" in my case. I am still testing.

  5. Claim: Pyrocat-HD is cost effective. 100% true. I bought the necessary chemistry to roll my own and it's dirt cheap.

Open Questions (things I am still exploring):

  1. Over what range of contraction and expansion will Pyrocat-HD work well +-2, +-3, +-4?

  2. Why bother with stand or semi-stand? With APX 100, I did not see the claimed edge effects. I had hoped for more visible mid-range tonal separation, but that seemed only to occur with very long stand time with some repeated agitations.

  3. What is the best way to increase/decrease local contrast with this developer. I realize that part of this lies with changing paper grade/filtration, but how is Pyrocat-HD best used to augment this?

  4. Has anyone tried Kachel's SLIMT techniques with Pyrocat-HD based development?

  5. What exactly is going on with Pyrocat-HD stand and semi-stand in terms of overall and local tonal range? In theory, the highlights should develop to the completion possible with the developer exhausting because of their rapid inductions times. The shadows should continue to develop for the entire stand time (lower induction rate), thereby providing greater effective film speed. BUT, does the extra stain buildup mean we are also getting more highlight compensation? What does this do to local contrast and overall negative scale?

  6. What is the optimal frequency of agitation during stand or semi-stand processing? I found no noteworthy differences (so far) between 1, 2, or 3 agitations but I may have missed it. NO agitation after the initial one did show some bromide drag on the hangered negatives.

  7. Has anyone tried stand or semi-stand with PMK as a point of comparison?
My interest in all this boils down to two things:

  • How do I manage the scene SBR to maximize usable negative scale?
  • How do I command desired local contrast in the key areas of the scene?
Both of these are much on the mind of people like David Kachel and Steve Sherman, but their approaches are very, very different. Kachel is going after these questions for conventional silver prints. Sherman appears to be optimizing for very long scale contact prints on AZO. Moreover, Sherman flatout says that his approach (which is only partially described in the public literature) cannot be changed at all. I surmise from this that his dilutions are designed to exactly exhaust when he gets the scale he wants out of the negative.

I like making pictures more than I like looking at a densitometer, so any helpful input from you all will be much appreciated.
 
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To many questions, I have no time for messing around, I use Pyrocat HD becaused I consistenltly get excellent negatives that print very easily.

Is it a better developer than say Xtol or Rodinal, on an individual negative level hard to say but over all definitely. I use a comparison withXtol & Rodinal beause they are undoubtably the best developers for the genuine old Agfa APX100, and Tmax and Delta films, however Rodinal is not so good with older type emulsions.

I had a discussion with Sandy King many years ago and he hadn't reaised Pyrocat HD was so good with smaller formats. he only used it for ULF work.

Ian
 
Based on my own many years experience with Pyrocat-HD at the normal dilution and 2:2:100 for pt/pd printing:

1. Check out Steve Sherman's EMA technique whereby he uses higher dilutions ratios with FP-4+ to reach the levels of expansion/contraction you're talking about.

2. Never developed APX100 in Pyrocat, but I can assure you that Fomapan 100 reveals an abundance of edge effects with minimal agitation. If you look at the emulsion side of a processed negative with light glancing across it, the image will have an etched appearance.

3. 2:2:100 will definitely increase contrast. I suspect any increase in B (the accelerator) will increase contrast, if you don't decrease development time, but I've never done this myself. Higher dilutions will decrease contrast, but, again, I don't do minus development so this will require some experimentation.

4. No

5. I think you have the theory correct. I don't know that there is "extra stain buildup" as any staining developer is a proportional stain based on negative density.

6. I don't do semi-stand or stand development (except for playing around occasionally with Fomapan 100 and Caffenol-C-L), but after many negs developed using 2 min agitation cycles up to 7 mins (ala Steve Sherman) I've yet to see any real difference in the quality/look of the negatives.

7. Never tried it, but my guess is that oxidation would be a real concern with PMK or any pyrogallol-based formula.
 
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