Quote Originally Posted by bobwysiwyg View Post
This would double the film surface area to 240 sq. in. Is the 40 oz. capacity of the Combi tank sufficient for this?
Bob, of course it depends on your choice of developer

ID11/D76 & XTOL which I use are both fine.

I use my dev at 1+1 and so use 500ccs of developer per batch - which for ID11 gives me the capacity of 400 sq inches of film surface (10 sheets of 10x8 = 800sq inches x 0.5L)

8 sheets of 5x4 have 160sq inches of film surface.

Even if you managed to do 12 sheets in a tank you only have 240sq inches of film surface.

1L of XTOL has the capacity to develop 15 sheets of 10x8 film

However, if I were using Ilford Perceptol - which has a much more limited development capacity at 4 sheets of 10x8 per Litre of neat stock - I would have to limit myself to 8 sheets.

If you look at your developer manufactures data sheets they have the surface area of film each 1L of neat stock can process.

Note:- 1 off 135-36 film has the same surface area as 1 off 120 roll of film and 1 off 10x8 sheet (or 4 off 5x4 sheets) - they all come out at 80 square inches of film surface.

Hope this makes some sense

Martin