Pyrocat: minimum stain and max sharpness

ParkerSmithPhoto

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Can anyone rec a good semi-stand or stand development time, agitation cycle and dilution for FP4 in Pyrocat-HD? I have been running 10 minutes at 25°C, with agitation every two minutes. I am just wanting to experiment and see if I can't pull some Beutler's like sharpness out of this combo.

Along with that, I'd actually like less stain masking and more grain. Based on some info in this old LFF thread, I did experiment with adding 6g/L of sodium sulfite and diluting the solution 25% weaker but I got some excessive B+F, although it did eliminate the stain. I am going to try same again with 2g/L and see what happens there. If anyone has any suggestions on minimizing stain I would appreciate it.
 

Andrew O'Neill

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I work with sheet film. I mix 10ml each of A and B into 1200ml water. I develop for up to an hour (depending on contrast) in BTZS tubes... stood vertically, tube filled right to the top ( main tube, not the cap). Continuous rolling agitation for one minute, let stand for 5 minutes. Rolling agitation for 5 sec. Let stand for 10 minutes. Then 5 sec rolling agitation. stand for 10 repeat until time is up. This won't help you with less stain. I can't help you there... but you'll end up with very sharp negatives. As far as I'm concerned, Pyrocat-HD is the best developer for extreme edge effects... I've also done this with 35mm and roll film.
 

awty

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I am no expert.....1+2+100 @ 21c with agitating for the first 30-60 secs then agitate for 10 secs every 3mins- 4mins..... or just use D76 and expose @80 iso.
Double b will hasten development and increase contrast.

This article may be of some help.
https://unblinkingeye.com/Articles/Pyrocat/pyrocat.html
 

john_s

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I use Pyrocat because I want some stain. If you want minimal stain, why not just use a non-staining developer?

I actually get not a huge amount of stain, because I expose generously and develop to a lowish contrast (shorter dev time). I think longer development would give me more stain (and more contrast which I don't want).

If you want more grain, a change of film might be the answer.
 

Raghu Kuvempunagar

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Using less than 3g/l of Sulphite can make stain unpredictable. When I was experimenting with sulphite addition to Pyrocat-HD, I sometimes got no stain and sometimes got light stain when sulphite was less than 3g/l. Settled with 5g/l as a sure way of getting rid of stain. I used a different film in my experiments, Orwo UN54.
 

Ian Grant

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You get the best sharpness where you have staining and tanning taking place increasing sharpness, it's why we usePyro developers. If you want no stain and an excellent developer use replenished Xtol.

Ian
 

awty

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Perhaps the developing temperature is too high, even at 23C developing and density build up swiftly and a bit under 20C it is very slow. Perhaps you can try at 20-21C..
Also normal strength stop bath can wash some stain away.
 
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ParkerSmithPhoto

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I ran the test again with 1g sulfite to 400mL for one roll 120. I got a very nice sharp negative with what appears to be zero stain and no indication of excessive base density. I will measure it later to be sure. I also ran the same image normal with stain. I will make some comparison prints at 16" and post them here. My goal was to get two matched negatives, one stained and one not, and see what the stain actually contributes to the final print.
 

Alan9940

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ParkerSmithPhoto said:
My goal was to get two matched negatives, one stained and one not, and see what the stain actually contributes to the final print.
Click to expand...

The stain contributes printable density and tends to minimize the appearance of grain. I've never tried to minimize or eliminate the stain in my pyro negatives, but given two negatives developed in the same staining developer--one with stain, one without--my guess is that the unstained negative would require a higher contrast filter to match the stained print. Even though you're adding a very small amount of sulfite, sharpness may be affected so I wouldn't necessarily compare sharpness between the two.

I've used Pyrocat-HD for years using minimal agitation techniques and, fairly recently, using Steve Sherman's EMA technique. Both generate very sharp negatives. As a matter of fact, with the films I process this way, if you hold the emulsion side such that light glances off at an oblique angle the negative appears to be etched. Personally, I've never seen that in any film I've developed in "normal" film developers. But, then again, I don't do stand type development with something like very dilute Rodinal.
 

john_s

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I've always wondered if the surface relief has an optical effect in the enlarger (maybe scattering at hard edges) which adds to the sharpness in the prints.
 

Alan9940

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ParkerSmithPhoto said:
What is your preferred EMA technique?
Click to expand...

I use roughly half-strength Pyrocat-HD in homemade tanks (tubes, actually.) Following a pre-soak, each tube is filled to the top and sealed with a plumbing stopper. Initial agitation is done by rolling the tube back-n-forth for a couple of minutes, then it sits upright for 6-7 mins, then rolling agitation for 15-20 secs, then sit, etc. Three stand/agitate cycles come after the initial agitation. Exact timing is based on individual film, of course.
 
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ParkerSmithPhoto

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Okay so I spent some time chasing this minimal agitation, semi-stand to max out sharpness routine, and for me it has been a flop.

This is a test with FP4 and Pyrocat, with semi-stand development for 16 minutes, agitating 5s every FOUR minutes.
The image is an 8x10 print cropped from a 16" projection. Look for the white speckles in the smooth tone areas. Totally unacceptable!

Then I tried agitation 5s every TWO minutes. I can still faintly see the speckles on a 16" print.

So I went back and pulled out some 11x14 crops from 20"(!) projections I did last year. FP4 was developed in Pyrocat-HD, plain vanilla 1:1:100, 25°C for 10 minutes, agitating 5s every 1 minute. Absolutely no speckles, unbelievably smooth and crisp, beautiful highlights and shadows, just everything you could want from a developer.

If you are running stand development, you may want to check some larger print sizes to see if it's really giving you smooth tones, like in sky areas. You would never see this at 11" and the two minute agitation cycle was passable at 16", but couldn't hold up to close inspection.

I'm going to stick with regular agitation cycles.
 
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esearing

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Note you improve acutance the longer the local exhaustion takes place. Part B determines the stain but don't go below 30% less than part A.
You can find my times and processing experiments over the last couple of years using HD and now M for FP4+ on my website.
 
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ParkerSmithPhoto

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esearing said:
You can find my times and processing experiments over the last couple of years using HD and now M for FP4+ on my website.
Click to expand...
Eric, I did see this post but based on the samples shown (mostly organic matter) I can't really see how the edge effects would make much difference compared to, for example, a building. And they would also tend to mask any irregularities in development compared to smooth areas like sky and solid fabric. Have you ever experimented with large prints, 16" and up?
 

Tumbles

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For FP4+ and Pyrocat HDC, I've always processed it for 20 minutes at 20C, with the standard 1:1:100 dilution. For agitation, I do 2 minutes initial, and then 10 second of agitation at the 15, 10, 5 minute marks.

I found that the fixer along with the stop bath can make a big difference with stain. When I first started with Pyrocat I was using an acid stop bath and Ilford rapid fixer because it was what I had on hand, and it's what I used with everything else. After I used it up, I switched to TF-4 fixer and a water stop bath, and the stain increased by quite a bit.

I think Pyrocat and FP4+ is a magical combination.

 
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