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View Full Version : Pyrocat HD or other developer for drum processing



jonathan smith
24-Sep-2004, 03:26
What are the favorite developers for drum processing, that would minimize any edge variation? I've been using D-76 (easy to find) but have heard about Pyrocat HD giving better uniformity. Any other favorites?

And, where do you get Pyrocat HD?

Thanks,

Michael Jones
24-Sep-2004, 07:54
Jonathan:

You could start here:

http://www.michaelandpaula.com/mp/index_skip.html

for a discussion of various developers and other's experiences. BTW, I use Pyro and D-76 depending upon my circumstances. D-76 is very hard to top. Good luck.

Mike

Bruce Watson
24-Sep-2004, 08:09
I doubt that Micheal and Paula can shed much light on your question as they develop by inspection, about as far from drum processing as you can get.

Edge variation in my experience is more of a drum thing than a developer thing. If the film isn't getting proper developer flow edge to edge, changing developer isn't going to have a great effect.

I've found that the Jobo expert drums are excellent in this regard. Edge to edge consistency is outstanding. I've used several developers, but find that XTOL 1:3 performs quite well with the 4x5 Tri-X I use and the continuous agitation of the drum. Clearly, YMMV.

Ken Lee
24-Sep-2004, 10:22
PyroCat HD is available at Photographer's Forumlary (http://www.photoformulary.com" target="_blank) and at Bostick and Sullivan (http://www.bostick-sullivan.com/main/Index.htm" target="_blank).



An excellent discussion of the subject you ask about, can be found at Unblinking Eye (http://unblinkingeye.com/Articles/PCat/pcat.html" target="_blank)



I use it sucessfully in a Jobo drum, and the trip is to rotate as slowly as possible, since oxidation spoils Pyro, and rotation, by introducing air, promotes oxidation.

Diane Maher
27-Sep-2004, 11:23
I use a Jobo tank with a Unicolor base and have no way of controlling the speed of rotation. Besides trying it, how do you know what is too fast for rotation?

Ken Lee
27-Sep-2004, 14:40
Read Sandy King's article,as mentioned above. See page 2 (http://unblinkingeye.com/Articles/PCat/PCat2/pcat2.html" target="_blank), where he says the following concerning "ROTARY DEVELOPMENT OF SHEET AND ROLL FILM":



"...However, when we develop film with rotary processing at high rotation rates the amount of sulfite is insufficient and general stain can result.. To counter this I recommend one of the following solutions: add 30% more of stock solution A when making up the working solution, or (but not also) add about 0.3 g/L of sodium sulfite to each liter of working solution. Both solutions have the practical effect of bumping the amount of sodium sulfite preservative in the working solution and this will slow down the rate of oxidation."</a>