Undeveloped 4x5 Edges?
I am relatively new to 4x5 development....a "veteran" of the darkroom, however. I am using a Jobo CPE2Plus and the 2509 reels in the 2553 tank.
I use Tmax RS mostly and periodically I have little purple or blue "undeveloped" edges on my film. The image is beautifully developed and the edge markings are nice and dark, but on the long edges of the sheets the emulsion hasn't completely cleared.
What should I do to avoid this?
Sounds to me like fixer isn't getting to those "undeveloped" edges. You can get rid of them by re-fixing the negatives - in room light and small trays should be fine.
It may be that developer isn't getting there either, but given their location, it probably doesn't matter.
You sometimes get that with roll film, too. It happens when the film presses hard up against the guides in the tank, and the processing chemicals can't get to it. Sheet film is thicker, so it may be more likely with the 2509 tank, although I haven't seen it so far. It shouldn't extend into the image area. (If it does, it's some other problem.) I should be harmless, but you can refix in a tray, as recommended above, if it bothers you.
Do you load the 2509 reels with the emulsion out, by any chance?
This is probably 'it'. The sheet springs outwards in the track, so load it with the emulsion side concave.
Originally Posted by grahamp
You can put the dry-but-imperfect sheets back in the tank, emulsion side inwards, and refix/rewash as you will probably find it more convenient (and with less risk of damage when you haven't done this before) than using trays.