I've just bought an HP Combi-plan T' tank to replace a stainless Nikor spiral tank which was scratching the 4x5 negs with occasional other problems.
I need to use inversion and have to use it in daylight mode, since I do not have a proper darkroom. I am only using it for B+W and currently am using DiXactol developer with Agfa APX100 film.
I have found a number of problems on first use, which hopefully experienced users will be able to offer advice, dodges or techniques to alleviate. Research led me to believe that the Combi--tank is the preferred dev tank for 4x5 and so either these problems are not significant, or more likely, I'm missing a few tricks and need more procatise!
1. Whilst loading film and placing film retaining clip on, I managed to get two sheets in one of the vee's preventing process fluids reaching top portion of one sheet. Also managed to get two sheets in one slot, despite trying to be careful and using fingers to locate sheet along loading guide.
2. Top valve is very stiff to rotate especially with wet fingers. If not closed fully, dev etc leaks out of vent.
3. It takes an inordinate amount of time to pour fluid in, 30 s or so I think. Clearly there is risk of uneven development and stop washes not being so effective. By applying breath pressure to funnel I was able to speed up drain process, but clearly have reservations about doing this on regular basis!
4. After the fix am I right that I can lift off lid to speed up wash water changes? If so, can I also do this for the staining stage of DiXactol developer?
Additional query, have just processed a 120 roll of APX400 which seems to have a much greater base fog. Or have I messed up on this too?!!!