Go look at some youtube videos, that will make it clearer. In simple terms though, they are:
- a recirculating heated water bath, temperature-controlled,
- some bottles for holding chemicals (in the water bath),
- a means of spinning a drum semi-submersed in the water (continuous agitation!), and
- (lift option) a means a getting fluids into/out of the drum neatly.
You can do whatever chemical process/sequence you like in them, as long as all steps can be at the same temperature and the temperature is between your tap-water temp and about 45C. They're compatible with all film and print processes. They're made mostly of ABS plastic.
A CPP2+ (mine) is a bit more than 1m long, 35cm deep and about 40cm high including lift. With the lift raised (emptying the drum), it's about 1m high. Higher if you use a longer drum. A CPE is smaller.
Price: maybe $200 for a CPE (won't take 3xxx Expert drums), $500-$1500 for a CPP2 with drums and $3000? for a brand new CPP3. Drums range from $30 to $700 depending on what and how (un)common they are.
35mm, 120 and 220 all run in the standard 2502 spirals (they work like Paterson spirals but are slightly larger diameter) and drums. 4x5 requires either 2509 inserts (4 to 6 sheets) to go in 2xxx drums, or an Expert drum (e.g. 3010, often $500ish, does 10 sheets at a time). Drums have extension modules, so you can chain a couple together to make a longer drum out of a shorter one and put more film in it. I do 6 rolls of 120 on 3 spirals in a 2553 tank and find that my limiting factor is drying space (even with a powered drying cabinet!) not Jobo time.
Tank Capacities is an informative read since it tells you basically all the tank options that are available.
You load the tanks in a dark bag, same as a Paterson. They're light-tight once closed, so you process in daylight. A film tank will fit in your typical dark bag, but a 3010 is an annoyingly tight fit for a normal bag. The bigger drums (for big prints) will not fit in your average dark bag.
Last edited by polyglot; 10-13-2013 at 08:19 PM. Click to view previous post history.