Yet another Pyrocat-HD question

Alan9940 · May 1, 2022

Need a bit of input from you experienced Pyrocat-HD users...

I've mixed this formula for many years in both p-glycol and distilled water. And, over those years I've had issues with the developer dying suddenly and doing other odd things. Today was one of those "odd things." I have a batch that's not quite a year old with the A part mixed in p-glycol. When I mixed it at 1:1:100 this morning, it revealed the usual color change when adding B. I mixed the working solution about 2 mins before use and by the time I was ready to start development the solution was CLEAR? Has anybody else seen this? I was expecting it to be that straw color that it takes on as oxidation sets in. I'm very careful about contamination so I don't think that was any issue.

Thank you for any insight shared.

John Wiegerink · May 1, 2022

Alan9940 said:
Need a bit of input from you experienced Pyrocat-HD users...

I've mixed this formula for many years in both p-glycol and distilled water. And, over those years I've had issues with the developer dying suddenly and doing other odd things. Today was one of those "odd things." I have a batch that's not quite a year old with the A part mixed in p-glycol. When I mixed it at 1:1:100 this morning, it revealed the usual color change when adding B. I mixed the working solution about 2 mins before use and by the time I was ready to start development the solution was CLEAR? Has anybody else seen this? I was expecting it to be that straw color that it takes on as oxidation sets in. I'm very careful about contamination so I don't think that was any issue.

Thank you for any insight shared.

No, never have, but I don't mix 2 minutes either. I usually gave it a couple of swirls with my stirrer and used it. JohnW

Sirius Glass · May 1, 2022

Did you test the developer on a leader of film. I always do with all developers, especially if I have not used them for a while.

Andrew O'Neill · May 1, 2022

I don't bother with glycol as it's too expensive up here. Just distilled water. Part A has been could for a year. I've even used stock that was almost two years old with no issues. When mixing up A and B just before use, it always has that very light peachy colour. Hey, as long as your negatives developed fine, I wouldn't worry about it.

Alan9940 · May 1, 2022

@Sirius Glass - That's what smart people do!

@Andrew O'Neill - Yeah, I've always read about the "extended" life of all the pyro developer formulas, but my personal experience doesn't exactly jive with that. When I mix Pyrocat-HD with distilled water, I keep it only for 6 months, then toss it; just don't trust it after that. The negatives were a little on the thin side, but certainly usable. I think I'll mix some fresh stock tomorrow.

Sirius Glass · May 1, 2022

Andrew O'Neill said:
I don't bother with glycol as it's too expensive up here. Just distilled water. Part A has been could for a year. I've even used stock that was almost two years old with no issues. When mixing up A and B just before use, it always has that very light peachy colour. Hey, as long as your negatives developed fine, I wouldn't worry about it.

But you do not throw out the stock chemicals after six months.

Dennis S · May 1, 2022

Alan9940 said:
@Sirius Glass - That's what smart people do!

@Andrew O'Neill - Yeah, I've always read about the "extended" life of all the pyro developer formulas, but my personal experience doesn't exactly jive with that. When I mix Pyrocat-HD with distilled water, I keep it only for 6 months, then toss it; just don't trust it after that. The negatives were a little on the thin side, but certainly usable. I think I'll mix some fresh stock tomorrow.

Thats been my experience also. I mix up a 250-500ml batch and then I know it will be good developing anything until I see thin negs then fresh Pyrocat HD. Once you use a Pyro developer it is very hard to switch back to the regular developers. One of the reasons why Propylene Glycol is hard to find is people use it for their Vap smoking so when I see that they obviously don't know the ingredients.

GregY · May 1, 2022

I've been using Photo Formulary Pyrocat for years...first the original and then the glycol. I've never had issues & use the (50 litre capacity) bottles until they run out.

Andrew O'Neill · May 1, 2022

If I have a bottle of stock A that's a year old, I always check it first... That's what the box of film rejects is for. I've got a lifetime supply of reject shots...
I've never had to "dump" old Pyrocat-HD down the drain, and I've been using Pyrocat-HD for almost 20 years.

Dennis S · May 1, 2022

Andrew O'Neill said:
If I have a bottle of stock A that's a year old, I always check it first... That's what the box of film rejects is for. I've got a lifetime supply of reject shots...
I've never had to "dump" old Pyrocat-HD down the drain, and I've been using Pyrocat-HD for almost 20 years.

I never had to dump anything as that is why I do the smaller mixtures.

Andrew O'Neill · May 1, 2022

Dennis S said:
I never had to dump anything as that is why I do the smaller mixtures.

Yup. Small batches are a good way to go!

greg zinselmeier · May 1, 2022

If you are mixing your own. Make sure your phenidone is fresh. If it’s old like 10 years old, it will die. I only use distilled water. I make a bottle of A @ 1000 ml. Or 500 ml if you use less in a year. I do not mix up B in a bottle. I start with 7.5 g of potassium carbonate in 100 ml of warm water. Add cold water to make 68 degrees. Then add 10ml of A then add 68 degree water to 1 liter.

Raghu Kuvempunagar · May 1, 2022

Alan9940 said:
When I mixed it at 1:1:100 this morning, it revealed the usual color change when adding B. I mixed the working solution about 2 mins before use and by the time I was ready to start development the solution was CLEAR? Has anybody else seen this? I was expecting it to be that straw color that it takes on as oxidation sets in.

The color change after 2 minutes is indeed odd. It can happen if sulphite was added to Part B which doesn't seem to be the case here. You might want to mix the working solution again from Parts A and B and check if this phenomenon occurs again.

greg zinselmeier · May 2, 2022

Alan9940 said:
Need a bit of input from you experienced Pyrocat-HD users...

I've mixed this formula for many years in both p-glycol and distilled water. And, over those years I've had issues with the developer dying suddenly and doing other odd things. Today was one of those "odd things." I have a batch that's not quite a year old with the A part mixed in p-glycol. When I mixed it at 1:1:100 this morning, it revealed the usual color change when adding B. I mixed the working solution about 2 mins before use and by the time I was ready to start development the solution was CLEAR? Has anybody else seen this? I was expecting it to be that straw color that it takes on as oxidation sets in. I'm very careful about contamination so I don't think that was any issue.

Thank you for any insight shared.

Has your water changed? Has your municipality changed it levels of chems. They put in the water?

greg zinselmeier · May 2, 2022

Alan9940 · May 2, 2022

greg zinselmeier said:
Has your water changed? Has your municipality changed it levels of chems. They put in the water?

Actually, not sure how old my Phenidone is...thanks for the tip. I'll buy some fresh and try, again.

I use distilled water for all my film developers. I suppose something about the water could have changed, but I doubt it.

Ian Grant · May 2, 2022

I've seen the colour change many times, and then it clears. It's the only developer I use now, as it’s so reliable I mix with water, it lasts 3 to 4 years even part used.

It collapses when the Sodium Metabisulphite has completely broken down to form Sulphite. It's important that you mix with relatively fresh Sodium Metabisulphite, it does go off.

Ian

Alan9940 · May 2, 2022

Ian Grant said:
I've seen the colour change many times, and then it clears. It's the only developer I use now, as it’s so reliable I mix with water, it lasts 3 to 4 years even part used.

It collapses when the Sodium Metabisulphite has completely broken down to form Sulphite. It's important that you mix with relatively fresh Sodium Metabisulphite, it does go off.

Ian

Thanks, Ian. I'm pretty sure my Sodium Metabisulphite is pretty fresh, but I'll check to be sure.

Alan9940 · May 2, 2022

greg zinselmeier said:
If you are mixing your own. Make sure your phenidone is fresh. If it’s old like 10 years old, it will die. I only use distilled water. I make a bottle of A @ 1000 ml. Or 500 ml if you use less in a year. I do not mix up B in a bottle. I start with 7.5 g of potassium carbonate in 100 ml of warm water. Add cold water to make 68 degrees. Then add 10ml of A then add 68 degree water to 1 liter.

I like this idea of mixing B when I need it. Reminds me of long ago when I used ABC Pyro, I would mix B just before development. It always seemed to me that the sulphite solution was the culprit of many issues with this formula.

juan · May 2, 2022

I have seen the B solution go off Even though everyone says it should not. I find it easier to just mix the carbonate directly into the working solution.

Ian Grant · May 2, 2022

greg zinselmeier said:
If you are mixing your own. Make sure your phenidone is fresh. If it’s old like 10 years old, it will die. I only use distilled water. I make a bottle of A @ 1000 ml. Or 500 ml if you use less in a year. I do not mix up B in a bottle. I start with 7.5 g of potassium carbonate in 100 ml of warm water. Add cold water to make 68 degrees. Then add 10ml of A then add 68 degree water to 1 liter.

I have some Phenidone manufactured by Ilford in 1961, it's as good as the fresh Phenidone I'm using, (well it was last year)

Ian

greg zinselmeier · May 2, 2022

in 2010 I bought from a company “A” 10g of phenidone. I mixed in 2020 pyro/hd.wasn’t getting the results I was expecting. I bought from company “B”. I used all the exact chemicals with the exception of the new phenidone. I shot two rolls of film of the same- no texture white wall in open shade on A very sunny day. Exposing each frame at a different e.v. Going through the entire gambit. Developed one in “a” pyro. Developed another in “b”. Same time/temp/agitation for both. Compared under x-rite densitometer. Significant difference. I now only buy from “B”.

john_s · May 2, 2022

juan said:
I have seen the B solution go off Even though everyone says it should not. I find it easier to just mix the carbonate directly into the working solution.

I recently mixed a batch of Pyrocat-HD and now that I have used almost all of my Neopan400 I tried the new batch of Pyrocat-HD with HP5+ which I'll probably settle on from now on. The test roll was disappointing, being quite low in contrast and the speed was not as good as my Neopan400. To cut a long story short, I suspected my part_B. I bought a large bag of potassium carbonate some years ago. Stored it in plastic bags inside plastic kitchen canisters, not perfect storage but probably good enough (maybe not?)

I tested the density of my Part_B and found it to be about 1.439. I used the data on the engineering toolbox web site to calculate that the Part_B should have a density of about 1.532. Using the same data, I concluded that my Part_B is only about 597g/L instead of 750g/L. Now I use more (x1.26) which is helping.

I measured correctly in making it up in the first place. Could my potassium carbonate have absorbed that much water from the atmosphere? It doesn't look lumpy.

Raghu Kuvempunagar · May 3, 2022

Even if Phenidone fails completely, Pyrocat-HD should still work reasonably well like Obsidian Aqua.

greg zinselmeier · May 3, 2022

Raghu Kuvempunagar said:
Even if Phenidone fails completely, Pyrocat-HD should still work reasonably well like Obsidian Aqua.

Quite right!!! However your shadow detail is less than optimal compared to reg. Pyrocathd ! Better synergy!!!

Yet another Pyrocat-HD question

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Yet another Pyrocat-HD question

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