Pyrocat-HD concentrate, shelf life question.

What About Bob

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I have seen answers concerning solutions of Pyrocat-HD that are working solutions but not of the concentrates themselves.

What would be the life expectancy of the developer, part A, in an unopened bottle? The packaging is still sealed and has been kept in a cool and dry place since late 2019. My guess would be probably as long as Rodinal and that's a heck of a long time. The part B is a sodium carbonate solution so that will probably last forever.

Soon I will be doing comparisons between Pyrocat-HD and D23. I see similarities from these two developers when I look at my negatives. D23 developed negatives resemble Pyrocat-HD but without the chocolatey stain and less acutance. I could get some of the acutance by diluting D23 at 1:3. I still have a bag of Pan F that has been under freeze. This will be a great film to do the comparisons with.
 

koraks

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Depends. Pyrocat in glycol, or water? It's most likely fine, though. Just do a clip test before you commit film to it to verify it isn't dead. Odds are it'll either be fine, or totally dead, but not something in-between. My money's on the former.
 
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What About Bob

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Glycol

There was a post that talked about the coloring.

If it the the "HD" version and If the solution gets dark brownish then it may be bad. If it is the MC version then the brown color doesn't indicate the solution as being bad and if it's the "P" version and turns dark pinkish then that doesn't indicate that it is bad either.

Update: I found the post and corrected the text above.
 
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Anon Ymous

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I made some Pyrocat HD in glycol back in 12/2019. It was brownish then, as it is now. My catechol is brown. 4 years later, it still works.
 
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What About Bob

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I will check the color and do a clip test. Thanks koraks

About 4 years in water. So my guess under my situation I should be in good shape then. Thanks Ian.
 
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What About Bob

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Thanks Andrew

Have you ever tried Pyrocat in TEA? I remember watching one of your videos using TEA. It was a comparison of Gainer's formula and Flic's developer. That made me think about TEA and wondering if it has ever been used with Pyrocat
 

chuckroast

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I mix my own. Originally, I did so with water, and that easily lasted well over a year, though it's likely it would have lasted longer.

I now mix with glycol, and the life expectancy in a glass bottle with a polycone style cap should be more-or-less indefinite. I dunno about 50 years, but I'd expect that developer to be good for at least 10-15.

To avoid this concern, I not only mix with glycol and store in bottles, I only make it in small quantities. I typically mix it in 500ml batches which means I am making new stock every 9-12 months, well within the lifetime of a glycol based Part A.

Well, what I really do is have 500ml in use, and a separate 500ml bottling of Parts A and B in storage, ready for use. When I deplete an active bottle, I replace it with the backup bottle, and then mix a new one up.
 
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Ian Grant

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I've only mixed Pyrocat HD Part A in Glycol once at double strength while living abroad. One bottle is left it's around 15 years old and still worked fine when tested last year.

While living abroad the Purocat HD in my darkroom only got used when I was on short trips back to the UK, that's when I realised it was keeping up to 4 years made up in water.

Ian
 

Andrew O'Neill

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What About Bob said:
Thanks Andrew

Have you ever tried Pyrocat in TEA? I remember watching one of your videos using TEA. It was a comparison of Gainer's formula and Flic's developer. That made me think about TEA and wondering if it has ever been used with Pyrocat
Click to expand...

No, I haven't... but I will! Gainer's CAT-P-TEA sounds interesting.
 
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