When Good Pyrocat goes Bad

[Andrew Tymon]

It does look like something is wrong with it. Have you thought about buying the dry chemicals and mixing your own?You would definitely know how old your stock solution is and you could make it in smaller batches and not waste as much if and when it goes bad.

[Drew Wiley]

Alkaline fixer like TF4 works best for removing the residual pink. But FP4 nevers clears completely of it like TMax, at least until there's either a period of years or strong UV fading due to enlargement. No big deal unless you're trying to factor in exact color printing parameters. I've often used FP4 for unsharp masking of color images, so am quite aware of the .02 to .04 remaining pink magenta density. It's almost undetectable on briefly washed TMax after an alkaline fix.

[Corran]

Eric, I haven't had Pyrocat go bad on me, in Glycol. The foaminess though, I get all the time, with mixed solution. I don't think that's an issue. Hoping some of those images came out - I see the old mill and stump in the river there from Sweetwater .

[domaz]

Pyrocat can go bad with very little warning in my experience. One subtle clue seems to be the solution color when mixed with water. If it's clearish it should be fine. Very light brown is ok, as it gets darker it can still work but caution should be taken. I could be totally off, but this seems to be the pattern for me at least.

[esearing]

The foaminess is an issue with the SP445 tank if you fill it to about 480mls. The foam seems to limit the agitation flow of the developer, at least I don't get the feeling of the fluid moving inside the tank.

The images are thin and "scanable" with my iphone app but I can tell they are underdeveloped as shadow detail is missing in the zone 3 and possibly zone 4 areas. IE the bricks in the mill on the darkest sides.

I have had a couple of folks email and confirm that the Pyrocat HD in Glycol goes bad suddenly rather than aging to a dark brown.

[Ray Van Nes]

I have had similar issues and it has shaken my confidence in this developer. When it works, it is brilliant but it very upsetting when you lose negatives that are important.

[Jim Noel]

I have been mixing my own Pyrocat in glycol since Sandy's first article about it. Sometimes the "A" solution lasts well over a year prior to use. No problems result. I have had the "B" solution get weak, but I haven't worried about it enough to test. I just throw it out and make more. Foaming is not a problem for me because I don't use any tanks other than JObo Expert occasionally. FP4+ clears well for me in Ryuji's fixer.

[Steve Goldstein]

The A solution of standard Pyrocat-HD has a little bit of water in it, and I understand that this can limit the shelf life. Because I'm not a huge-volume user I've started using the Pyrocat-HDC, which contains no water at all in A (B is the same).

[koraks]

The A solution does not necessarily contain water. The ingredients can directly be mixed in glycol, which is not extremely hygroscopic either. However, both the phenidone and the catechol will oxidize due to the traces of oxygen in the solution, which are added every time you stick a pipette into it or shake/stir the bottle. It is also possible that a manufacturer uses a stock solution of phenidone in alcohol to make the comcentrate; however, in any appreciable volume operation (anything from a liter or more) this would be in my mind unnecessary, and in practice unlikely, and thus hypothetical. Even then, the small amount of alcohol and the water that will invariably be part of it (4% of the alcohol volume) would be quite minimal. A stock solution that is light coloured has not oxidized appreciably, as a significantly oxidized stock solution will be extremely dark.
The B solution going bad is virtually impossible; this is potassium carbonate in an aqaeous solution, which is about as stable as it gets. It'll last years without any change, won't grow mold, etc.

[Andrew O'Neill]

Been using Pyrocat-HD for 16 years. Never had a problem. I just developed a couple of sheets from solutions mixed back in January. Both A and B are mixed from scratch using distilled water. Stored in brown bellows bottles, in a cupboard that is never higher than 20C.