Re: Pyro Processing Errors
use trays..never have these problems again
I would gladly answer your questions but I don't use drums
Re: Pyro Processing Errors
Quote:
Originally Posted by
peter schrager
use trays..never have these problems again
I would gladly answer your questions but I don't use drums
Well my darkroom is currently my bathroom, and sealing it up whenever I want to develop film kind of blows. From my understanding, Pyrocat-HD was created specifically to work better in drums/tanks than other staining developers, so it must be possible to get this to work. I appreciate the suggestion though.
Re: Pyro Processing Errors
it should work well in the drums...must be something to do with the drum itself..pyrocat is a pretty flawless developer
Re: Pyro Processing Errors
Usually, this kind of problem has to do with either incorrect mounting of the negative in the drum (emulsion facing out instead of in), contamination of the drum with a surfactant (eg. Photoflo), or insufficient developer volume/non-level placement of the drum. Furthermore, presoaking sometimes seems to create more problems than it solves (although some people experience the opposite) and speed of agitation influences development evenness, with particularly higher speeds (>40rpm) causing problems. I would hesitate to connect the latter two potential causes to the bubble pattern however and look in the direction of the other issues first.
Re: Pyro Processing Errors
I see this as insufficient developer and its foaming and adhering..
Re: Pyro Processing Errors
Looks like photo-flo residue to me...likely acquired by using too much concentrate in the final rinse. Does not look possible as pre-soak residue, as you seem have decent density otherwise.
I process my FP4's in trays - with the first step being a three minute presoak with just a few drops of photo-flo added before going into Pyrocat HD (in glycol).
My experience with Photo-flo is that its generally better to use less than more, to help mitigate residue problems. This goes for both pre-soak and final rinse procedures.
Not sure if switching to Pyrocat MC would make a difference here.
I'd also pay attention to Korak's suggestion about correct drum placement.
OR...perhaps you have foaming issues with your TF-4? Hmmm...
Re: Pyro Processing Errors
I've processed 1,000s of sheets of 4x5 (not 8x10 as you are doing) FP-4 in a JOBO and have never seen anything like this. I'm thinking that it is either insufficient developer, or a Photoflo problem as Bob and John have suggested. I found that the best way to use Photoflo is to use Edwal LFN instead. I always use it in its own separate tray so as not to have residue where you don't want it.
Re: Pyro Processing Errors
Thanks for all of the replies guys! I've never had photoflo in this tank, always in a separate tray, so that shouldn't be the cause. I thought 500ml would be plenty of developer, but I can try with more. Maybe I'll try without a presoak as well, and see if I can reduce the RPMs on the motor base. And maybe I'll try refixing some of these negatives in a tray... if the markings are caused by the fix, a refix should correct it, right?
Re: Pyro Processing Errors
Yes, if it's insufficient fixing, you could just fix them again. Fixer does have the tendency to flow a little less evenly in my experience, but on the other hand, the bubble pattern that you show here I've never seen linked to fixing but always to development.