PyrocatHD 1+1+100 Question

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Ian-Barber

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Just need some clarification...

My development tank uses 500ml of solution.
If using PyrocatHD at 1+1+100 this means that I will use 5ml of A and 5ml of B and 490ml of water.

With this amount of A+B is there enough to develop 4 sheets of 5x4 film
 
Yes, 500ml at that dilution is more than enough to process 1 10x8 sheet, 4 5x4 or 1 120 film.

Technically 1+1+100 should be 510ml, however I've always worked as you suggest 5+5 to 500 as measuring jugs that allow 500ml to 2 litres don't have small increments like 10ml.

Ian
 
https://www.photrio.com/forum/threads/pyrocat-hd-capacity-w-semi-stand-agitation.23396/

"One roll" of either 35mm or 120 is more or less equivalent to one sheet of 10x8 and one sheet of 10x8 is equivalent to four 5x4 sheets, so this might be a useful guide. Nobody seems to have exact figures for the precise instant of exhaustion.
In extreme conditions of near exhaustion, (which I presume is not the case here) the density of the neg might be a factor. A black cat in a coal cellar would consume less active agent than a white cat on a snowdrift.
 
David, I have exhaustion figures, they are quite complex because they relate to the exhaustion of replenished developers and the amount of various components needed to replenish to maintain the stock solution at a constant working strength.

The work was done by Ilford in the mid 1950's when they were working on Axford & Kendall's PQ fine grain version of D76/ID-11 which became Autophen a photo finishing machine developer for the B&W D&P trade. This was unique because it used a topping up replenisher rather than bleed so was extremely economic.

Ian
 
Thank you Ian,
I think the information would be well beyond my needs, but it's comforting to know that it exists. I hadn't realised that the different components expire at different rates, but it does explain why replenisher is not the same as developer.
 
The common form of replenishemnt is Bleed, here you discard some developer and add the replenisher to replace it, this is useful in keeping Bromide and Iodide levels lowish in developers like D76/ID-11 where to higher a level of Bromide suppresses the activity of the Metol. It's slightly wasteful because you're discarding developer that's still usable.

Unlike Metol Phenidone can withstand much higher levels of Bromide with no drop in activity, this lead Ilford to experiment with PQ versions of ID-11 (D76) and they measured the exhaustion of the main components Phenidone, Hydroquinone and Sulphite, they already knew how to maintain the pH through years of ID-11 use.

In the US the formula for Autophen was mistakenly claimed to be for Microphen by the Photo Lab Index and this was perpetuated in various publications over the decades.

Somewhere I have a spreadsheet comparing the actual levels of various components in dilute developers like Pyrocat and Rodinal, I can't remember the others offhand but I was looking at exhaustion and the minimum levels require for effective development (it was about 8-10 years ago but I have it somewhere..

Ian
 
The question here is will approx. 500mls of Pyrocat HD at the 1+1+100 diution develop 4 sheets of 5x4 film ? (Or one roll of 120 film or one roll of 36 exp. 35mm film, all of which have about the same area)
From my experience of using it I will say "yes, easily" When I used to use Pyrocat HD I regularly tray developed 4 sheets of 5x4 film in only 300mls. I also regularly developed single rolls of 35mm film in a 300ml tank.
I should say that I always used metol, rather than phenidone. Not sure if this makes any difference.
I gave up on Pyrocat in the end. It gave very nice results but in comparative tests I found I could get almost identical results with dilute Perceptol, and Perceptol negatives were easier to print in the darkroom. Yes, I know that the stain you get with Pyrocat is supposed to be an all round good thing, but I found it only made it harder to estimate the correct paper grade. And as for the stain limiting highlight density and therefore controlling contrast in a high contrast lighting situation. I found Perceptol at 1+3, or ID11 at 1+3 works just as well.

Alan
 
My experience with Perceptol or ID-11 at 1+3 is the results are quite bland, yes highlights are controlled and don't block up but at the expense of compressing the tnality.

A better dilution is 1+2 while not listed but easy to extrapolate from Ilford's datasheets times. It gives superb results comparable to replenished developer. Some of the best 35mm negatives I've processed and printed were shot on FP4 with an Exacta VX1000 and CZJ lenses and processed in ID-11 1+2 At the rquest of the photographer).

I know Bill Spears found the same with FP4 and Preceptol which he uses 1+2.

Ian
 
Ian, I have to say that my experience with Perceptol and ID11 is quite different from what you describe. A few years ago I did a whole series of tests with various developers. I used 35mm FP4 and HP5. I chose 35mm because differences would show up more readily in the final prints. The tests consisted of exposing several rolls of film on the same subject in constant light, then clipping off short lengths of film and developing them in various dilutions of Rodinal, Xtol, ID11, Perceptol and Pyrocat HD.
I won't describe all the results, but one thing I did find was that there was no difference in the finished prints between ID11 at 1+2 and ID11 at 1+3. Ditto Perceptol.
I found that FP4 looked great in Perceptol. And for 35mm FP4 my standard practice is to use Perceptol at 1+2. Or 1+3 for film exposed in contrasty sunlight. Pyrocat HD gave results very like Perceptol. Equal sharpness. Equal fine grain. And equal lack of compression in mid-tones. The latter is very important as it gives a sort of "peaches and cream" look. Definitely not bland.
I preferred 35mm HP5 in dilute ID11, as it gives the grain a bit more bite than you get with dilute Perceptol. And my standard practice with HP5, in all formats, is to develop it in ID11 at 1+2, or 1+3 if exposed in very contrasty light.
I had previously used Rodinal quite bit. It is supposed to be very sharp. But my tests showed me that, in fact, it isn't as sharp as ID11 1+2. Dilute Rodinal is also supposed to work well as a compensating developer, i.e. it holds the highlights back whilst allowing the shadows and mid-tones to develop fully. My tests showed that dilute Perceptol, dilute ID11, and Pyrocat HD all outperformed it in this respect. Rodinal mid-tones were compressed, and shadow detail wasn't there. But it was grainy! I even tried Rodinal semi-stand, i.e. 4 initial inversions then one inversion every five minutes. This was claimed to increase the compensating effect, and keep up the film speed by bringing detail out in the shadows. But this turned out to be another internet myth.

Doing these tests was hard work, but worth it. I now develop everything in ID11 at 1+2 or 1+3, except 35mm FP4 which I develop in Perceptol 1+2 or 1+3.

Alan
 
Alan, I've done the same tests, so have others, and it's what suits your work.

I'll just disagree, having spent many years working as a Photo-chemist and knowing that others think the same including people who produced FP4, Perceptol and ID-11 :D

Ian
 
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