C-41 in the Combiplan
I've been frustrated during my temporary living in China (hah - approaching 3 years now, but this summer we finally return home to the USA) to find a quality provider of C-41 development services for my sheet film (4x5). I have no problem with getting quality medium or small format, but the only provider that could do quality C-41 of sheet film stopped doing it. All the others give me poor results (wavy skies usually - clear problems with inconsistent flow, or bad agitation, or something).
I've shied away from doing it myself because in my temporary home here I don't have my old Jobo, which used to give me great results. Lenny Eiger talked me into diving into development in my sink, which I've begun to do.
I have a Jobo tank with the sheet film spiral holder, but have been very unsatisfied with it. I have found it to be extremely difficult to pour the fluids into the top without going too fast, having some of the fluid spatter over the edge of the funnel, and drip onto the film, rather than filling consistently from the bottom as it is supposed to. The result is spatter patterns in the finished sheet that ruin the image, even worse than what I get from the commercial developers.
I have a Combiplan tank, and it has a filling system that assures the fluid rises smoothly from bottom to top without splatter. Unfortunately, it takes a good 30 seconds to fill.
I'm using the Tetenal 3 bath kit, the only kit I can find in Beijing.
I decided to try the Combiplan, but to use the reduced temperature development times so that I could better accommodate the slow filling time of the Combiplan.
The sheets came out wonderfully consistent, no splash marks, no waviness at all - just spectacular. Except that at the lower temperature, they had a color cast that I can't seem to correct using my unmentionable post processing tools. I've of course read PE's posts on this, and expect this is due to the temperature.
So, long story short, my question is this (before I blow through more test sheets): Do I really need to worry about the fact that the Combiplan takes 30 seconds to fill and drain, in a 3 minute 15 second development cycle? It seems the top part of the sheet will get on the order of a minute less time in the soup. When using the longer process (8 minutes as I recall), I didn't notice any difference in the density of the sheet from top to bottom, so the fill/drain time doesn't seem to be an issue with longer times.
I have other alternatives (using a funnel when filling the Jobo tank, for example), but I'd really like to focus on the above question in this thread. Have others used the Combiplan for the 3:15 cycle successfully with its slow fill/drain times?
I believe Nova did a dip'n'dunk system based around the Combiplan tanks - If you have a real dark space, maybe this would be an option. As the tanks are no longer available new, a few rectangular food containers could be pressed in to service.
I'm sure I could do this with dip and dunk in darkness, but before I go there, I'm hoping someone has an answer to the question of the effect of the long fill/drain time and short development time.
If no one has any experience with it, I guess I'll just have to bite the bullet and give it a try. What's one sheet of C-41, after all...
C-41 in the Combiplan
Just to close off this thread... I was able to successfully develop c-41 in the slow draining and filling combo plan, and the results were fine. However, I did end up creating a true darkroom environment so that I could take the lights out dip and dunk approach instead. I find it easier, actually. And the negs come out great that way.
I use the combi plan tank for the initial water presoak, and some 1.5 liter juice jugs for the other tanks. They happen to be almost identical dimensionally to the combi plan, so the rack fits well without requiring a lot more fluid to cover the film.
The juice jugs are nice for other reasons. I can cover the chemistry while the tank is not in use, so that I don't accidentally drip liquid from one tank to the other. They also pour well, so it makes chem handling easy after I finish.