Processing large format film by hand is difficult, and there are many pitfalls, or many opportunities to improve in the craft. Don’t get me wrong, processing large film is not really much different from processing 35mm or medium format, but the larger size creates problems. When I first started 4×5 film processsing I used 5×7 trays in total darkness. I started off using trays since I had everything that I needed all ready in the darkroom. Developing in Trays in total darkness sucks. You can’t see anything (obviously), but it is also hard to keep track of individual sheets if you are developing more than one. I had some problems with scratches showing up on the negatives as they would rub together. The only positive, is that it is the cheapest way to start developing black and white ( no color developing here since you have no way to control temperature reliably).
Pros: Cheap entry, Loading film in to the tray is easy.
Cons: Large amount of chemistry required, scratch’s negatives, no temperature control, total darkness required
After a while I upgraded to a Yankee tank. These are also terrible. They are not light proof, so you still need to be in the dark. The tank had slot s that would hold the film for processing and only moderately scratched up the negative ( which was an improvement over tray developing for me). The tank itself was incredibly tedious to load, and you had to be very careful not to put 2 sheets in one slot. Putting 2 sheets in one slot will cause one of the sheets to not develop properly as the chemistry could not freely flow along the negative.
Pros: Kept the negatives separated while developing
Cons: Loading was difficult, Developing was difficult , the tanks required a large amount of chemistry.
After the yankee tank, I picked up a HP Combi Plan 4×5 tank next. I stuck with the combi plan for a couple years, it is not a terrible daylight tank and they are not being made or sold any longer, so you will need to find them on the used market. The company marketed the combi plan as:
“HP’s Combi-Plan 4×5 Film Developing Tank will hold both sheet film from 6.5 cm to 4″x5″. Its adjustable carrier will hold up to six sheets, and can be used with wet and dry films. A locking retainer clip secures the film within the carrier, and the leak-proof lid allows for inverse agitation, like in 35mm tanks. It also comes with a loader for easy, foolproof loading in the dark.”
Believe me when I say that is all dirty lies. This thing leaks like crazy. You do not want to do inverse agitation. Aside from the problems with leaking during agitation, this is not a bad option for developing black and white film and color film. The film carrier can be finicky to load, and there is a risk of loading more than one sheet per slot, but it was much improved over the Yankee tank. Also I never had any problems with scratches.
Pros: Light tight tank. Can accommodate multiple sizes of films.
Cons: expensive system, Loading was difficult, Leaks during inversion agitation , the tanks required a large amount of chemistry.
I purchased a SP-445 Daylight tank recently. This was a kickstarter project that was successful, and I have seen the tank for sale for a while now. I was developing a batch of 4x5s a while ago and mis-loaded 2 sheets in the Combi-Plan tank, and both sheets were ruined because of uneven developing. That was pretty much the last draw for me, and I ordered the new tank that promised to solve all of my problems.
The tank itself was $87, so not really expensive but not cheap, either. The SP-445 uses about 1/2 of the chemistry to develop than my older method, so that will save quite a bit as time goes on. The film holders load very similar to normal 4×5 film holders, so loading the SP-445 is already a familiar process. The tank is light tight, and does a good not not leaking if properly sealed. I have never used a tank that is perfectly sealed (all the tanks that I have ever used leak a little, and the SP-445 is similar to the best of them).
Pros: Smaller chemistry requirement, tank does not leak when processing, relatively easy to load in complete darkness,
Cons: Can only develop 4 4×5 sheets of film at one time
I would Recommend this new film tank over any of the tanks that I have tried, it is the best option I have used to date.