Tube and PMK

Hi,

I'm reading pyro book by Gordon Hutchings, and he says that tube processing don't work with this developer. I used to developing with PyroHC but I have PMK developer in my stock so I would like to use it, and I would like to try it with my tube. I developed a negative and I added to working solution EDTA 1%, and I think it's work, but I would like to know also your experience of this developer.

Thanks

Stefano

Pyrogallol developers, like PMK, are quite sensitive to aerial oxidation. You can't add more antioxidant (the usual ones are sulfite or ascorbic acid), because that will destroy the stain. Pyrocat-HD and Rollo-Pyro were designed to minimize these problems. Actually, some people have had good luck with PMK in tube processors. I guess it depends on your individual technique and maybe on the age of the solution.

I don't seem to have any trouble with it. I'm not really worried about what happens to the stain, though. I only use it because it's so cheap. I use the stuff from Artcraft Chemical, with the buffer, restrainer or what ever it is added. Works fine. Just be sure you use enough developer so it doesn't poop out on you.

The main problem is that the very small amount of developer people typically use with tube development, combined with the long exposure of the surface of the film to air, tends to cause more B+F than one might otherwise want.

To compensate for this I would recommend adding a small amount of ascorbic acid, as you find in Rollo Pyro. With pyrogallol developers you can add a failry large amount of ascorbic without killing the stain. What I would do is mix up a 1% solution of ascorbic acid in TEA or glycol and add about 10-20ml of this solution per liter of PMK. This will cut back a lot on B+F.

Sandy

glennfromwy said:

I don't seem to have any trouble with it. I'm not really worried about what happens to the stain, though. I only use it because it's so cheap. I use the stuff from Artcraft Chemical, with the buffer, restrainer or what ever it is added. Works fine. Just be sure you use enough developer so it doesn't poop out on you.

Click to expand...

photo8x10 said:

Hi,

I would like to know also your experience of this developer.

Thanks

Stefano

Click to expand...

I've had good results using PMK in a Jobo system by splitting the development time in half and using fresh developer for each half.

I mix the first developer and pour into the tank. While it's rolling, I mix the second batch.

I spoke with Gordon Hutchings about developing in a rolling tank and he added that one should use plenty of developer for better results. So, I make sure I don't scrimp on the fluid.

It worked. Sky areas are fully developed without the blemishes.

I also noticed that the first developer isn't as dark when dumped from the tank.

This method doesn't save on developer but it does let me develop without having to handle the tank so much.

Just some of my experiences....

Bill Riley