About the PMK Pyro developing process

[younghoon Kil]

I am developing with PMK Pyro for a month ago.
Here is the my developing process.

● Develop: Usually 10 ~ 11 mins, continuous agitation first 30 seconds, then 1 inversion every 15 seconds.
● Stop: Tap water 2.5 mins
● Fix: TF-5 for 4mins, continuous agitation first 30 seconds, then 30 seconds agitation every 1 mins.
● After Bath: PMK Pyro developer 4 mins, continuous agitation first 30 seconds, then 2 inversion every 30 seconds.
● Rinse: Tap water 30 mins.
● Edwal LFN: 1 mins, continuous agitation.

The results of the development meet my expectations.
However, I am not sure whether this process is correct or general.
Regarding the PMK Pyro, it is difficult to find out more about the developing process even with Google search.
I would be glad if you could give me some more advice.

p.s. I am sorry that my english is poor.

[Peter Lewin]

Gordon Hutchins, the developer of PMK, changed the directions to eliminate the after bath in used PMK; he discovered that all it did was add to base fog. I have also read that a 5-minute pre-soak increases the staining effect. Since I always pre-soak anyway (most of my developing is sheet film, but I also pre-soak 120 roll film, and I don’t use PMK on 35mm) I can’t vouch for that effect.

[Drew Wiley]

I use it for all formats, and presoak even roll film in inversion tanks.

[younghoon Kil]

I heard about After Bath.
But I do not know yet if it is better or not.
Thank you.

p.s. If I do a pre-soak, can I add 20~30 seconds to the development time?
p.s.2. I use 4x5 and 120 film.
p.s.3. And I develop with an SP-445 tank.

[RJ-]

Hi Young Hoon,


Are you making it from the powder: http://jeffreysoper.com/node/124

as a Stock A:B:Water in the ratio of 1:2:100.

The Stock B is Sodium Metaborate (alkaline) which controls the rate of the process. This is the simplest version [Stock A: Metol, Bisulphite, Pyrogallol Stock B: Sodium Metaborate]. If yours is pre-packed liquid, there isn't much you can do, other than follow the instructions and mix 1:2:100.

In powder form, Stock A composition can be varied with buffer or substituted; you can add 1% Benztriazole (I tend to do this, partly because all of my film stock is now so expired since it was all discontinued over 10 years ago); you can do many things to the developer, including division and subtraction. You can take away the Sodium Metaborate of Part B and use Potassium Hydroxide etc.

However before doing anything off the basic recipe, perhaps you could start:

1. Which film are you using
2. Which ISO have you standardised for your film to achieve 11 minutes of development.
3. How are you measuring 'the results meeting your expectations'. Have you decided which printing technique (cold cathode or VC light?) and paper yet?

You've mentioned there isn't a lot about the developing process with Google? I'm guessing, that the humans amongst us who are alive, still haven't been replaced by googlebots, and if you ask us humans directly, and not google about the specific developing process issue you wish to clarify, the googlebot will pick it up afterwards for ever

I tend to use PMK Pyrogallol for Kodak Technical Pan - ISO 16 in roll & 5x4" sheets using the Kodak 'cocktail' shake method (you will need a hanger for sheet film) thrusting the film vertically and rotationally in energetic shaking for 8-9 minutes (rather shorter) with a 30% surplus of developer. We write 'cocktail' to mimic the action of mixing an alcoholic drink by a bar tender, in a certain way (but this is a metaphor, and not very accurate as well). The pyrogallol content exhausts rapidly, and so fast shaking [of the film: but not of the whole tank, or you form bubbles, which cause unevenness], stops streaks, lumpy tones or drag of spent byproducts in the chemistry.

The aura green stain effect of PMK Pyro has been described here. You can improve it, choose it, deselect it, by switching composition of your Part A:B. You choose which accelerator (e.g. Potassium Hydroxide instead of Sodium Metaborate) for contrast control, and restrainer for extreme densities:

https://www.youtube.com/watch?v=r_zK-yWKa4M

I think this is a great youtube clip. Someone explains here in a few minutes, what took us humans years to work out. Google is great after all.



Going back - your original starting PMK Pyro workflow is ok. Read all the other posts with recommended changes to your basic idea. You're moving it towards consistency now.

Enjoy developing!

Kind regards,
RJ

[younghoon Kil]

I use PMK Pyro in liquid form.

-- http://www.largeformatphotography.in...-4x5-negatives

I started the black and white film developing a year ago, but I could not develop it properly because of the dark slide problem in the Toyo-View film holders.



Only a month ago I realized that it was a dark slide problem.
There were 12 dark slide problems.
(I sent an e-mail to the MAC Group a month ago and they said they would send me new dark slides. But I have not received e-mail yet.)

Anyway, I wanted the highlights and shadows detail to be rich, and I got to know PMK Pyro about a month ago.
I found a rough ISO setting using Stouffer's TP4x5-31C film.
And I got satisfactory results that I did not experience with XTOL. (Of course, I know I had little experience with XTOL.)
I do not print in darkroom, scan with an Hasselblad X1 scanner, and print using an Epson large format printer.

Thank you for your valuable advice.

[RJ-]

I use PMK Pyro in liquid form.

-- http://www.largeformatphotography.in...-4x5-negatives

I started the black and white film developing a year ago, but I could not develop it properly because of the dark slide problem in the Toyo-View film holders.

Hi,

Is this image intended for demonstration of the Toyo darkslide problem?

I can see an uneven mottling pattern, however this does not fit classically with problems at the imaging stage. But I'm not seeing a Toyo darkslide problem (i.e. mechanical failure) in your image since I don't use or understand Toyo. I think you have diagnosed this DDS problem separately on your other thread - the batch from Toyo seem problematic - another problem on top of your development struggles!

To me, from the (limited) internet view, the mottling pattern appears like a film development stage where operator error. has crept in. Perhaps if you have more examples from the other 12 images using these slides, the pattern of imaging or development defect might become clearer. If your image is an example from your PMK Pyro development, it may need you to reflect on whether the mottling has happened due to an inadequate grasp of the specific agitation method needed for for PMK Pyro. Chemically, this kind of result can happen if there is localised exhaustion of the developer, forming pockets of depletion of active Pyrogallol and build up of byproducts which become visible on the negative.

The PMK Pyro is a reasonable choice for giving an expanded contrast range (i.e. highlights and shadow detail). Stepwedges and X1s are fine if you are into that kind of technological alchemy with a 19th century developer.

Stop bath issue - 30seconds in Ilfostop is fine, however your fixer may deplete faster than you wish at this brevity, or on reuse of Ilfostop. You achieve a cleaner wash during the stop cycle for times around a minute, before transfer to the fixer. If you use the fixer for anything other than PMK Pyro, you will need to be careful with cross contaminating your workflow. If you only use PMK Pyro, then this is fine, since all of your workflow is then contaminated anyway.

Perhaps I am wondering if a solid grasp of film development basics helps, before leaping into PMK Pyro. Otherwise, deficiences in the basics become superimposed on the specific PMK Pyro developer issues resulting in all kinds of frustration and repetition of new kinds of troubleshoot.

Kind regards,

RJ

[Drew Wiley]

Just standardize your presoak. I like 2 min.

[younghoon Kil]

Just standardize your presoak. I like 2 min.

I'm sorry I do not understand.
Does it mean I do not need to change the development time?

[bob carnie]

I split the development into two distinct times with fresh.. also I stain ..