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Questions on pyrocat-hd

1kgcoffee

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I have some liquid pyrocat-hd, enough to make 10L. I've tried googling but no luck on the answers.

Question #1- It say to mix 1a:1b:100 parts water. Is it good practice to mix a concentrated solution for convenience, ie 1a:1b:10 water and then dilute 1:10 water when developing? This is much easier as I don't yet own a graduated cylinder

Question #2- How long will the solution keep?

Question #3- Can you use regular stop and fixer (I use ilford rapid fixer)

-thanks,
1kgcoffee
 
Last edited:
No. 1 - Well, I never heard of anyone doing a serial dilution such as you suggest. What you need is a syringe that can measure up to 10 mL (commonly found here in drug stores for administiring baby medicine) and something that can measure up to 500 mL like in a typical measuring cup you might use in baking.

No. 2 - I use it up to 16 months in well sealed bottles, using marbles to eliminate air space. The B solution should keep almost indefinitely.
 
Thanks for the response, one more question. Can I use regular stop and fix (ilford) or do I lose the benefit of pyro by doing so?
 
I use water stop and regular Ilford fix. Just mix up what you need per session. The stuff will last almost forever a concentrate.
 
Keep the stock solutions separate. I have used solutions that were a year old. They were kept in accordion bottles (not the thin light ones), in a dark, cool cupboard. For most films I dilute 1+1+100. I use a stronger solution to get more stain when I develop HP5. I use a very mild stop consisting of citric acid or vinegar, followed by Ilford Rapid Fix.
 
Water or dilute stop is recommended for P-HD. Too much acid reduces stain.

Ditto on NO to #1. Syringes are usually available at feed stores, and I'm pretty sure you have a few of those in Calgary. But you probably should have a couple graduates before anything else, they are essential! A nested set of 3 is nice.
 
i would recommend the use of an alkaline or at least neutral fixer. if im not wrong sandy king mentioned that a neutral fix is just as good. i prefer alkaline fixer.
water as a stop is all you need.
mix dev. just before use.
chris
 
I use a vinegar stop, highly dilute and an alkaline fixer for my Pyrocat-HDC negatives. I have two syringes labeled A and B with permanent black marker. You do not want any and I do mean any cross-contamination of your A and B solutions or you'll be sorry. I also have two little clear plastic containers marked A and B with their little lids that were used for "eye contact lenses" that hold 1.5ml each. I'll use those if I want a slightly more stiff dilution. I will repeat this once more............DO NOT GET ANY SOLUTION "B" INTO YOUR STOCK SOLUTION "A" CONTAINER!
 
Don't mix the two stock solutions together until just before you develop. Working solution life is very short due to oxidation. As others have said, find a way to measure the small amounts you need to be able to mix and use this developer one-shot. I use syringes that I got (for free) at the local pharmacy. Graduated pipettes work too. I keep dedicated syringes; one for Sol. A and a separate one for Sol. B to ensure there is no cross-contamination (which will kill Sol. A quickly).

I use a half-strength stop bath with no problems. A full-strength stop should also work; I don't think the acid environment can remove the stain... Maybe Sandy will chime in here.

Best,

Doremus
 
I purchased two children's medicine dosing syringes and labeled them A and B so no risk of cross contamination. Mix the amount of developer needed just before use.You cannot premix and store this developer. Best to use two 30 second water rinses instead of stop, or use stop at half strength, followed by a neutral or alkaline fixer such as Formulary TF-4 or TF-5. I use Eco Pro Neutral.
http://www.pyrocat-hd.com/
 
I agree with the above. I draw up 20ml from A in one syringe and dilute to 1000ml in a bottle, draw up 20ml B separate labelled syringe and dilute in a second bottle. The when ready to pour in the developer pour both 1000mls into a 2litre jug at the same time so thoroughly mixed and then add to the tank. Minimum time from mixing to working solution getting to the films. I use water stop then Ilford Rapid Fixer.
 
go to any pharmacy and ask for a 10ml syringe. get 2 as mentioned above, 1 for A and 1 for B. keep the solutions separate until you are ready to develop. measure out your, say, 500ml water, then 5ml A, then 5ml B and off you go. as also mentioned above the stock solutions will last a very long time if they stay separate, especially if you got the glycol version.

just use a simple water stop. I use TF-4 or TF-5 fixer and it keeps the stain perfect.
 
Developers of this type are sensitive to oxidation so never dilute the original concentrate until you are ready to use it. In other words do not make an intermediate stock solution.
 
Thanks for the responses. To be on the safe side I'm getting TF-4.
 
I used TF-4 because someone said it's what I should use when using a staining developer. When comparing negatives that were fixed in TF-4 and Ilford Rapid fix, I could see no difference in stain. I saw no reason to use TF-4. Pretty expensive to bring it up here, too.
 

I did the same when I first started using staining developers, not that expensive here, but even mixed with distilled water the ammonia smell put me off. I found (at the time Silvergrain brand) Legacy Pro, EcoPro Neutral fixer. I much prefer it to other brands, slightly higher in price, but no smell, longer lasting, more prints and films per liter, can be mixed 1+4 or 1+7, fast wash times.
 
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