Pyrocat - P

[fhovie]

After years of happily preferring Pyrocat HD, I gave Pyrocat - P a try (Thanks Sandy) and here are my impressions. (Now - I did not do a detailed test with sensitometry for each increase in light level as a scientific exersize) This is merely the subjective response from developing a bunch of tri-x rolls and comparing them with p'cat hd.

I can now understand the love peple have for p-aminophenol (Rodinol) It is a little grainier that the phenidone version (HD) but what happens in the midtones is interesting, if not astonishing. It appears there is a richness of mid tone separation and detail.

Erconta 6x9 - 110 tessar handheld
neg scan
tri-x at 200ASA
8 min p'cat -P at 72F

I am not suggesting that this is not a likely result with HD but it seems the midtones just stand up and take notice with p-aminophenol. Development times and film speed are identical to the HD version. I did not try it for 8x10 contact printing yet. I am not sure if the results would be similar or not.

Now - having said this. I am not going to rush out and make it my new replacement for HD. I am guessing that maybe the HD has a slightly more linear response. I do feel a need to do some more testing though. I know Sandy was interested in the -P for use in constant aggitation environs. I gave up that mode early on when I saw the loss of accutance from the constant aggitation. I do think that this version would certainly be a Rodinal replacement though - probably an upgrade. I'll bet Rodinal is a whole lot grainier than the -P version. This brew certainly needs more exploration.

 

[gainer]

Next try Pyrocat M and especially Pyrocat MC.

 

[MMfoto]

Do you have any more negs scanned? I would love to see some more examples...

 

[sanking]

After years of happily preferring Pyrocat HD, I gave Pyrocat - P a try (Thanks Sandy) and here are my impressions. (Now - I did not do a detailed test with sensitometry for each increase in light level as a scientific exersize) This is merely the subjective response from developing a bunch of tri-x rolls and comparing them with p'cat hd.

I can now understand the love peple have for p-aminophenol (Rodinol) It is a little grainier that the phenidone version (HD) but what happens in the midtones is interesting, if not astonishing. It appears there is a richness of mid tone separation and detail.

Thanks for posting your results with Pyrocat-P. You sure have a good range of tones in that scan, from detail in the deepest shadows to the highlights. Nice job of exposure and development.

I can not see anything in the curves of Pyrocat-HD and Pyrocat-P that would explain a difference in mid-tone tonal values. But real negatives and prints often tell us things that we won't find looking at curves.

What I find very interesting about the Pyrocat variants -HD, -M and -P is that they all have a very distinctive look in terms of grain and apparent sharpness, which makes them different developers, but they all require almost identical develoment to reach a given CI. That means you can use any one of the three variants and not have to adjust your times, which should be useful for folks already familiar with Pyrocat-HD.

Pyrocat-MC is slighly more energetic and if you try it I would recommend reducing develoment times by about 5-10% compared to Pyrocat-HD and the -M and -P variants.


Sandy

 

[vet173]

That was my experience also with -P. With expanded development, the midtones didn't didn't display the coresponding stretch usually experienced. It may not be a silver bullit, but I consider it a highly polished nickel plated one. When I showed samples to my mentor, ( a brooks grad in 66 ) he was blowen away. They looked a little different to me but he was seeing a lot more than I could. His first comment was about how midtones were treated. This is from an individual who, when talking about developer modifications with Ansel Adams, Ansel was taking notes.

 

[pauldc]

What I find very interesting about the Pyrocat variants -HD, -M and -P is that they all have a very distinctive look in terms of grain and apparent sharpness, which makes them different developers

Dear Sandy, it would be very helpful to have a very brief summary of the different looks (in terms of grain and sharpness) of the -HD,-M and -P varieties as you mention in the above quote.

I currently use -HD which I love, but would be interested in the benefits and differences I might expect if trying one of the other versions.

Thank you!

 

[sanking]

Dear Sandy, it would be very helpful to have a very brief summary of the different looks (in terms of grain and sharpness) of the -HD,-M and -P varieties as you mention in the above quote.

I currently use -HD which I love, but would be interested in the benefits and differences I might expect if trying one of the other versions.

Thank you!

Paul,

I must admit to some guilt for not having already provided this type of information. Unfortunately, since I introduded the -M and -P formulas, and Gainer added to the -M to make it -MC, I have simply not had the time to carry out extensive comparison testing of the new formulas.

However, here are my observations as of this moment, and they should be seen as preliminary because they are only based on one or two tests.

1. Of the variants Pyrocat-HD and Pyrocat-MC appear to give the most speed.

2. Pyrocat-HD is the least grainy and gives very smooth gradations between tonal values.

3. Pyrocat-M and -MC also have nice tight grain and slightly higher apparent sharpness than -HD.

4. Pyrocat-P has the most pronounced grain (but still very tight) but also appears to have the greatest apparent sharpness.

These comments are based primarily on microscope inspection of in-camera negatives. This is adequate for evaluating grain, but much more needs to be done for high confidence in the question of apparent sharpness. The much more would include tests for apparent sharpness and resolution that eliminate the optical system of a camera, together with some carefully controlled field experiments. I plan to do some testing along these lines when I return in July or August from my trip to the northwest US and Canada.

Sandy

 

[donbga]

Paul,

I must admit to some guilt for not having already provided this type of information. Unfortunately, since I introduded the -M and -P formulas, and Gainer added to the -M to make it -MC, I have simply not had the time to carry out extensive comparison testing of the new formulas.
Sandy

Is there one thread that have all of the formulas listed?

Thanks,

 

[Tom Hoskinson]

Is there one thread that have all of the formulas listed?

Thanks,

Don, the various Pyrocat formulas are spread across several threads:

The current Pyrocat-HD formula is here: (warning, it’s quite a way down in this thread)

(there was a url link here which no longer exists)



Pyrocat-HD

Stock A
Distilled Water -- 750ml
Pyrocatechin -- 50g
Phenidone* -- 2.0g
Sodium metabisulfite -- 10g
Potassium bromide -- 1.0g
Water to 1000ml

*Mix first in a small amount of alcohol, then add to the stock solution.

Stock B
Distilled Water -- 750ml
Potassium carbonate -- 750g
Add slowly while stirring the potassium carbonate to the water. Should make a total of about 1000ml. There will be an exothermic reaction that will cause the solution to warm up as you mix it.

You can use a variety of dilutions. I generally recommend 1:1:100 for silver papers and 2:2:100 for alternative printing but other dilutions may be better for specific purposes, for example 1.5:1:150 for stand development, 5:3:100 for very low contrast scenes with alternative processes, etc.


The Pyrocat P and Pyrocat M formulas are here:

(there was a url link here which no longer exists)



The Pyrocat MC formula is spread out over several Apug threads, here is my summary of the Gainer/King formula and my mixing directions:

My directions for mixing Pyrocat MC
________________________________________
Pyrocat MC “A” Concentrate

Triethanolamine @38°C (100°F)------------- 7-8ml

Distilled or Deionized water @38°C (100°F)--- 5-6ml

Metol ----------------------------------2.5 gram
Ascorbic Acid --------------------------4.0 gram

Pyrocatechol ---------------------------50.0 grams

Propylene Glycol @38°C (100°F) ---------600ml




1. Place a 250ml or 300ml Pyrex beaker (or equivalent) in a water bath (water about 115° F - 46°C) Pour the warm (38°C) Triethanolamine and Water into the beaker and mix them together (I use a magnetic stirring hotplate – but a stirring rod or paddle will also work ok).

2. Stir the Metol and Ascorbic Acid into the mixture of Triethanolamine and Water, after the mixture has become fluid and uniform, allow it to sit for about 10 or 15 minutes, and then mix in about 200ml of the warm Propylene Glycol. Stir until the solution is uniform in color and viscosity.

3. Transfer the 200ml + solution obtained in Step 2 to a 1 liter container (I use a Pyrex Beaker). Rinse the small beaker from Step 2 with warm Propylene Glycol, then pour the glycol rinse into the 1 liter container (while stirring).

4. Stir the remaining warm glycol into the mixture in the 1 liter container. Keep the 1 liter container in a warm water bath or on a hot plate such that the glycol mixture temperature is maintained between 120°F and 130° F (49°C - 55°C) When the mixture is uniform, stir in the 50 grams of Pyrocatechol. Continue stirring until the mixture is again uniform, then add sufficient Propylene Glycol (with stirring) to make a total volume of 1.0 liter.

5. You are finished making the Pyrocat MC concentrated “A” solution. I divided mine into 2 500ml bottles for storage.

6. Use this Pyrocat MC “A” concentrate with the Pyrocat – HD “B” concentrate to make the working developer.

 

[donbga]

Don, the various Pyrocat formulas are spread across several threads:

Thank you very much Tom!

 

[sanking]

The Pyrocat P and Pyrocat M formulas are here:

(there was a url link here which no longer exists)

Tom

Thanks for putting all of the together. Just one more note. When I originally introduced the Pyrocat-P and Pyrocat-M formulas they contained a small amount of potassium iodide as a restrainer, which was described as optional. I have since decided there is no advantage at all in the restrainer and my current version of these formulas eliminates it. So, the most current version of the -M and -P formulas are as follow.

Pyrocat-P
Stock A
Distilled Water at 120ºF 750ml
Sodium Metabisulfite 10.0g
p-Aminophenol 5.0g
Pyrocatechin 50g
Distlled Water to 1000ml

Pyrocat-M
Stock A
Distilled Water at 120º F 750 ml
Metol 2.5g
Sodium Metabisulfite 10g
Pyrocatechin 50g
Water to 1000ml


Mix the chemicals in the order given.

Pyrocat-P can be mixed in glycol if that is desired. Just heat the glycol to about 150º F and mix the same way as water. Pyrocat-M must be mixed water unless you first change the metol to base, which is not all that complicated. Or, try the Pyrocat-MC formula.

Stock B solution is the regular Pyrocat-HD solution, a 75% solution of potassium carbonate.

If you have good development times for Pyrocat-HD for your favorite films the same times used with Pyrocat-P and Pyrocat-M should give almost identical results. Pyrocat-MC is slightly more energetic and you should reduce times by about 5-10% compared to those of Pyrocat-HD.

Sandy

 

[fhovie]

I store pcat hd in glass = even with air in the bottle, shelf life is over a year with no problems. I have yet to see a benefit for messing with glycol or TEA for shelf life concerns of HD. I do use TEA for ascorbic acid or sodium ascorbate mixtures though, for the antioxidation qualities. I think there is not nearly enough time to work on both art and every iteration of these formulas. I find p-aninophenol interesting enough to explore it further. How many developers can really be useful? I have PC-TEA and 510 Pyro for full film speed applications (med format) with good sharpness. (they seem to give very similar results - medium size sharp grains one with stain and one without) I have pcat hd for sheet film and larger roll film formats. Semi stand HD is very similar to what the -P version does normally including increased grain size. There is Microphen for pushing and XTOL for smaller formats. Jeepers. Although it is wonderful to have so many great choices, and that they all effect the outcome of an image, like lighting, lenses or film choice, it sometimes seems there would be no time for image making for the sake of chemistry and science - which, on its own, doesn't hang on the wall.

Having said that, I spent yesteday hiking around silver creek south falls (Near Portland OR) with my Tachihara and a box of FP4. I think I might be working on some real keepers this week. They will most likely get souped in semi-stand p'cat HD and compared with some done in -P I really think I will see nearly identical results. If that is the case, I'll likely finish this with HD being the developer I continue to keep on hand. If -P still has this magic midrange - I may have to migrate to it. I will need to see what it does to the sky in terms of smoothness when enlarged (4x5 or 6x6 to 11x14 or 16x20) I know HD will give me wonderful skys with TRI-X or FP4.

 

[sanking]

Although it is wonderful to have so many great choices, and that they all effect the outcome of an image, like lighting, lenses or film choice, it sometimes seems there would be no time for image making for the sake of chemistry and science - which, on its own, doesn't hang on the wall.

In the end the same thing could be said about films, cameras, lenses, methods of development, etc. The amount of choice can be at times overwhelming. Many of would probably do better work if we stuck to just one of everything, but the temptation of excess is great.

I am accutely aware of this temptation right now as I am packing for a long trip out west. So am I taking one camera and one lens? Nope, taking three different outfits (6X7cm, 5X7 and 7X17) with multple lenses for each camera.

One film, you ask? No, I have TRI-X 320, TMAX-400, Efke PL100, and HP5+ in LF and ULF, and several different B&W and color emulsions for the 6X7.

One tripod, then? No, have two of them packed already, and am thinking of taking a third.

But at least I won't have to think about different developers for a while!!

Sandy

 

[donbga]

In the end the same thing could be said about films, cameras, lenses, methods of development, etc. The amount of choice can be at times overwhelming. Many of would probably do better work if we stuck to just one of everything, but the temptation of excess is great.

I am accutely aware of this temptation right now as I am packing for a long trip out west. So am I taking one camera and one lens? Nope, taking three different outfits (6X7cm, 5X7 and 7X17) with multple lenses for each camera.

One film, you ask? No, I have TRI-X 320, TMAX-400, Efke PL100, and HP5+ in LF and ULF, and several different B&W and color emulsions for the 6X7.

One tripod, then? No, have two of them packed already, and am thinking of taking a third.

But at least I won't have to think about different developers for a while!!

Sandy

Under the seat or checked baggage?

Have a great trip!

 

[sanking]

Under the seat or checked baggage?

Have a great trip!

Don,

Fortunately some excess is possible since I will be traveling on the road in my old but very dependable Pathfinder.

Sandy

 

[fhovie]

For me it is checked baggage. So - much simpler. One field 4x5, 2 lenses, 8 holders, 2 boxes of film - FP4 and TRI-X, one tripod and all under 20# with filters, spot meter, loupe, dark cloth etc. Most of my subjects require at least a mile hike. Another good day of shooting - mostly Mt Hood today. Multnoma seems a little low on water this trip. Didn't even shoot a frame this time there. Had ice cream instead.