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I screwed up... pyrocat HD first time

Mammoth_research

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Hello!
I am frustrated today because I had two rolls of 120 TMAX100 (same tank) come out COMPLETELY blank (No numbers or edging visible)! This means that there was no development at all. I have my pyrocat HD in glycol 1:1:100 stored in a large "carboy" container with spout from ULINE. It is WHITE CLEAR-ISH plastic and is not too far away from a window. Did I ruin my developer with light? Air?

Help me out please! Thanks very much
 
I may have solved my own problem... the developer should not have been diluted and stored for as long as it had been.

A follow up question then: Do folks tend to simply mix what developer they will need for an evening of processing films and store away the rest of the concentrate? I was dumb to mix it all up at once it seems...
 

I always mix Pyrocat just before using it. It's a developer that oxidizes quickly. Come to think of it i've never had a film developer that i diluted and stored...... always mixed from concentrate.
 

Yes, mix it as a concentrate and store. When you are ready to develop a roll or whatever you then mix it 1 part A, 1 part B and 100 parts water. The stored concentrate will have a very long shelf life. Even longer (years) if Part A is mixed with propylene glycol instead of H2O.
 

Hi,

I just mix new pyrocat concentrate / stock solution when little is left or the solution gets too old - say two years in brown glass bottles in water not glycol. Never store the working solution.
 
Thanks all for the replies! That is definitely the issue here and I will fix this next time. Live and ya learn
 
Store stock solutions A and B in separate containers to combine at time of use. Use separate measuring syringes and avoid cross contamination at all costs.
 
Rick A said:
Store stock solutions A and B in separate containers to combine at time of use. Use separate measuring syringes and avoid cross contamination at all costs.
Click to expand...

Yes, I label my syringes A and B. If you cross contaminate, you're in big trouble.
 

That seems to be the problem. I've had stock P/Cat for many years and only mix up what I will use in the day. As once I went to a Pyro developer (510 Pyro, PMK, or P/Cat HD) I have trouble going back to regular developers as it's extremely inexpensive and works VERY well.
 
juan said:
IIRC Sandy King said in his first articles on Pyrocat that the mixed developer lasts only an hour or two.
Click to expand...

Yes, that sounds about right. It's certainly still active after 45-60 minutes, at least without too much agitation. Beyond that point, it'll start to taper off.

Mammoth_research said:
Do folks tend to simply mix what developer they will need for an evening of processing films and store away the rest of the concentrate?
Click to expand...

That's the way it works for many developers, yes, although not all. For instance, developers like XTOL and D76 are packaged with the intent that you mix it all up, and then either use full strength, or dilute only a little further before use, and possibly being reused and/or replenished. On the other hand, developers like Rodinal, Pyrocat and to a lesser extent also HC110 are designed to be diluted down quite far to working strength immediately before use, and then discarded.

In general, if you need to dilute a lot (ratios of 1+25 and higher), it's safe to assume you have to dilute immediately before use and discard after use. With developers you mix from powder or that are used at low dilutions (less than 1+10), there's a good chance that they'll keep in liquid form fairly well and might be reused.

Pyrocat with its typical dilutions of 1+50 ~1+100 clearly falls in the former category. Since it essentially lacks antioxidants, nothing protects it from oxidizing under the influence of the oxygen dissolved in the water and thus, it has a very short life once diluted to working strength. Developers like D76 and XTOL on the other hand are positively loaded with antioxidants (mostly sulfite) and thus, they tend to survive much longer. Paper developers also generally fall in this category, which is necessary because they're used in trays (large surfaces that will promote oxidization) with frequent agitation and for hours on end.
 
I have mixed Pyrocat-HD in glycol a little over a year ago. The concentrate is as if freshly mixed. I make a working solution immediately before use. It oxidizes very quickly - should not be stored or reused.
 
Storing A and B solutions separately and free of air is a good start. Measuring the dilution correctly is important. Always test the developer before developing rolls of film. Fortunately one only makes one mistake like that.
 
Sidd said:
Why not use fresh disposal syringes everytime?
Click to expand...

Because it's super easy to rinse them when done and it keeps trash to a minimum. The reason for two marked syringes is to not cross contaminate the solutions which causes them to die.
 
Sidd said:
Why not use fresh disposal syringes everytime?
Click to expand...

Cuz I'm a Hollander! I'd rather take the time to rinse after every use than throw away a perfectly good syringe. Besides, our landfills are filling up far too fast as it is.
 
Rick A said:
Because it's super easy to rinse them when done and it keeps trash to a minimum. The reason for two marked syringes is to not cross contaminate the solutions which causes them to die.
Click to expand...

My question here is, if you cleanse the syringes properly, would the cross contamination still happen?

Kudos to both of you for your concern. I myself use a 10 ml. measuring tube (graduate) and measure 5 ml. of A and B solutions and add to 500 ml water required in my developing tank. Later clean it up thoroughly. Till now my solutions are doing well.
 

I also use 10 ml graduated cylinders.... @ marked A & B. It's an easy and inexpensive way to prevent cross contamination.
 

I did that for a while. I used the little plastic cups with caps that you use to clean your eye contact lenses in. They held exactly 12ml when filled to the top. I would fill ten at a time with A and B solutions, each mark A&B on the cap. When I was ready to develop, I would just grab two off the shelf and mix a batch. I wouldn't reuse them and eventually ran out, but it was a slick and easy method.
 

Mark each syringe for one solution and don't use for the other.
 
Sidd said:
Why not use fresh disposal syringes everytime?
Click to expand...

Because generating waste "just because" is, like, bad practice? Dunno about you, but I personally hate throwing stuff away just like that. It's not about saving $0.001 either.

It's super easy to use pipettes or syringes and simply rinse them and/or label them clearly.
 
Clean glass pipettes properly and you don't have to label them for Part_A and Part_B. I don't subscribe to separate kitchen utensils, like cutting boards, colour coded for different food types. Just clean them.

I have preferred to add the parts of Pyrocat to the water, not mixing the two parts together then pouring them into the water. I assumed that mixing the concentrates might accelerate reactions leading to faster deterioration, but I don't remember if I read that or just imagined it.
 
If you are going to use this developer for a while, it would be a good idea to uses pipettes or other measuring tools that are or are marked in a way that is clearly different from each other, so that inadvertent switching becomes less likely.
 

Yes, that's my method also. I don't know if it makes a difference which one, A or B, you add to the water first, but I always add A last and have never seen any ill effects.
 
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