Which volum PMK Pyro for 8x10` film

[Juergen Cullmann]

I want to develop my Efke 25 8x10 film in PMK Pyro. I use 24x30 cm trays.

Is 515 ml solution (5+10+500) enough for one sheet or is it possible to develop more than one sheet in 500 ml.

What would be a good developing time to start with?

Tank you

[Eric Woodbury]

I'm using 600cc of the standard dilution (although your dilution doesn't have any more developer and I think you would be developer limited first) to develop 6 sheets of 5x7. It is plenty. So that would be 6cc of part A to develop 210 square inches of HP5+. That is almost 3 sheets of 8x10. I should think a liter of PMK would do 4 sheets of 8x10 film. ...But is that enough liquid in that tray size for 4 sheets?, I don't know.

[David A. Goldfarb]

One sheet of 8x10" (or 1 roll 35mm or 120 or 4 sheets 4x5", etc.) per 500ml is the recommended capacity of PMK, but I find that I get more even results when I develop at least two sheets at a time using the tray method, with at least 1 litre of solution in 11x14" trays. I also prefer ABC pyro to PMK for negatives to be contact printed.

[Mark Sampson]

You are risking uneven development with only 515ml of developer in a 24x30cm tray. I can develop up to 8 4x5 sheets with 2L of PMK in an 8"x10" tray.

[Chauncey Walden]

I have always used (successfully!) 300ml in a tray for a sheet of 8x10 mainly because it took that much to give good coverage of the film and to promote agitation . In view of the discussions above, I went back to The Book of Pyro to see what Gordon says about capacity. In talking about developing roll film in tubes, he says that 7 35mm reels can be developed in 1100cc's. That works out to only 157ml per 8x10 equivalent.