The Changing Colors of Pyrocat

Here is my interesting if not unimportant observation on PyrocatHD:

When it is fresh and you make working solution it barely turns amber - BARELY. Enough to wonder if it is working. After two months, making a working solution makes an odd blue green color - at least I know a reaction occured. Then after 6 months when I am at the bottom of the stock solution bottle - It turns a majestic purple when I mix working solution. AFAICT it works the same in the begining as it does at the end. Also - I have been keeping the stock solution stored in brown plastic accordian bottles. I noticed the edges of the bottle darkening on the Part A Solution (only) Kinda makes me thing this stuff creeps through plastic. Humph - I guess it will be 5 bags of marbles and dark glass for the part A next time around. Anyway - I wonder if any of you other Pyrocat Users have seen the same thing??

Also - I am completely satisfied with what Pyrocat does for contact prints for 8x10 negs. I did up a bunch of 4x5 negs the other day and started to realize that the fine grain results I get with Pyrocat might be too fine ... The images do not (in some ways) appear as sharp as I recall many of my older PMK negatives looking. - Especially on larger blow-ups. I like the look of the mid tones and smooth gradations acheived with Pyrocat and am thinking of making several negs of several different types of images and using the cat on one and PMK on the other and seeing just how different the accutance is and see if it is an acceptable trade off for grainieness. When I first started using Pyrocat it was to have a developer for all my negs. Although it does work well on MF, I like using PC-TEA on MF negs now. SHEEESH - I may wind up with the cat for 8x10 and PMK for 4x5 and PC-TEA for MF? sounds wierd. Maybe?

I'm with Sandy on this one - the only color I've ever seen my Pyrocat-HD is a light amber color. I have noticed it darken slightly over time, but not very much.

Perhaps there was some residue left over in the bottle from a previous concoction? I would suggest using a different bottle for your next batch to eliminate that variable.

I am with Sandy and Ken on this one as well. Very light amber only, even with old A solution (9 - 10 months old, partially filled bottle, no marbles).

Maybe it is your water - or a contaminated storage bottle? Accordian bottles are very hard to clean, in my experience. I don't use them any more for that reason.

If you want to keep the A solution for years, use propylene glycol as the solvent instead of water.

KenM said:

I'm with Sandy on this one - the only color I've ever seen my Pyrocat-HD is a light amber color. I have noticed it darken slightly over time, but not very much.

Perhaps there was some residue left over in the bottle from a previous concoction? I would suggest using a different bottle for your next batch to eliminate that variable.

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My experience wouldbe the same as Ken,Sandy and Tom. My A solution gets darker brownish but no hint of blue

Phill

Hi,

The only useful comment I can make is that the color changes you are getting are what I routinely get when I dilute the stock solutions of PMK. They are associated with correct and normal PMK behavior. Maybe something is going on (like the above mentioned contamination) which is making your Pyrocat mimic the PMK color changes.

Jay