Re: When Good Pyrocat goes Bad
I must say that I'm suspicious also. I've been using Pyrocat HD in glycol for years with great success...but the most recent batch exhibited foaming upon mixing (1:1:100 from liquid stock), which I'd never noticed before - and my negatives appeared thin and a bit mottled. I always mix from stock using distilled water and must say I have my process down pat...so I do not share this lightly and am frankly distressed.
Re: When Good Pyrocat goes Bad
I have never had a failure with Pyrocat, but I use the Pyrocat M version and mix the A and B solutions from scratch myself using distilled water and storing the solutions in wine bottles with air tight stoppers.
Re: When Good Pyrocat goes Bad
I doubt very much that pink negatives has anything to do with Pyrocat going bad. I have personally never observed any condition in which any of the Pyrocat variations produced a pink color.
On the other hand, if the developer has degraded to the point where it has very little energy one would expect that the pink color of the anti-halation backing would be even more prominent since there would be little image formation and the fixer would then remove the remaining silver.
As for the developer going bad prematurely, I have never observed that except in cases where there was cross-contamination. Pyrocat HD solution mixed in water should be good for at least 6-9 months even in partially full bottles, mixed in glycol the solution should be good for several years.
Foaming is something I have never seen and so far as I can determine there is nothing in the Pyrocat chemicals or glycol that should cause foaming. It is possible that the stock solution was mixed incorrectly, by either the user or a third party. Places like B&S and the Formulary probably keep a record of the production batch and would know that if there have been complaints about the batch.
Sandy
Re: When Good Pyrocat goes Bad
Marginally off topic, but proof how threads can be useful on related topics. Was mixing up a working solution of PMK this afternoon, and saw that the “A” stock solution was dark brown-red, clearly oxidized as mentioned earlier in this thread for Pyrocat “A.” So, back on topic, I used my good Pyrocat developer instead!
Re: When Good Pyrocat goes Bad
Quote:
Originally Posted by
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.
I always fill to about this limit, would you suggest lowering the amount we put into the SP445?
Re: When Good Pyrocat goes Bad
Quote:
Originally Posted by
IanBarber
I always fill to about this limit, would you suggest lowering the amount we put into the SP445?
Ian , You need some air in the tank for the fluids to move easily or you have to be a bit more aggressive when inverting. There is a tab that sticks out into the fill area, that is fill limit and still allows the squeeze to create vacuum. I only use one holder which creates a bit more space.
I sent a request to Bud at PF for info about batch age and his thoughts on the shelf life. Last year my February purchased batch went bad in October. So I am guessing 9 months if not refrigerated.
Re: When Good Pyrocat goes Bad
Eric - I was curious so I looked up when I ordered my 50L kit, in Glycol. I received it in early December last year. Still working fine. I am getting low, and so I am going to put the rest of the chemicals in the smaller 10L kit bottles I kept from my previous order, for less oxidation. Do you decant your larger kits into smaller bottles ever?
Re: When Good Pyrocat goes Bad
I like to decant my pyrocat into small bottles of type 1 plastic that I repurposed, usually medicine or supplement bottles. A pharmacy may sell you some and they come in various sizes. I liked the Target pharmacy bottles as they were a deep red color and some came with a insert for a syringe, which I thought was a smart idea.
Re: When Good Pyrocat goes Bad
So according to Bud at PF my batch #188 was mixed in 2013 (Purchased December 2017). They have newer batches mixed since then, but due to low demand it hangs around. Y'all need to order more!!!
Corran, I did pour some of the 500ML into a 100ML bottle that I work from to prevent the cross contamination. I use the old marbles trick to keep the original bottle close to full. That is why I was disappointed my original nearly full bottle failed too.
I estimate I used about 200mls of Part A of the 500ml. So economically I might do better to buy a 100ML bottle every 6 months since I use it very dilute for one sheet at a time.
I needed some other stuff from elsewhere so placed another order of the non glycol Pyrocat HD version. In theory, I should at least be able to see a color shift as it goes bad.
Re: When Good Pyrocat goes Bad
Quote:
Originally Posted by
IanBarber
I always fill to about this limit, would you suggest lowering the amount we put into the SP445?
Haven't used Pyrocat yet, but I fill to 450ml. I find if I go much more, it will leak out of the caps.