Film area size

[MattKing]

In case people haven't noticed, this thread is in the sub-forum titled: "

B&W: Film, Paper, Chemistry​

So it isn't surprising that many/most of the answers aren't referencing the Kodak "Z" documents for colour film processing.
It wasn't until the 6th post that we even had an inkling that the OP was asking about colour film, and even then the question wasn't asked in a way that made it clear that the question at issue was in respect to capacity of un-replenished colour film developer - and certainly we never knew for certain whether or not the OP was asking specifically about Kodak Flexicolor developer, or any particular Kodak film.

The correct answer about the undoubtedly important question of how much film my litre of developer can develop is to ask the questions: "Which developer, which films and which processing regime? With answers to those questions, we can refence the available manufacturer's information to find the capacity answer.

 

[DREW WILEY]

High volume film processors do need to take into account volumes in relation to cumulative film surface area and replenishment rates. Much of that is automated. For most of us, however, it's more just a matter of having enough solution in a drum to get the film evenly developed. So you use the solution volume the drum or tank specifies. It's that simple.
Don't reuse the chemistry, and never mix up more at a time than a daily session demands; that will help with consistency.

 

[Vaughn]

@Vaughn Not your call. What is insignificant for one is unusable trash for another. ..

I should pay more attention to the dates -- ten years old! I did check the original Post and the first few posts before mention of color. My posts were about B&W material -- thanks Matt for the heads up.

PS -- Steven...I never recommended ignoring manufacturers recommendations -- only your particular interpretation relative to B&W work. But even with color, if you base the amount of chemistry needed for the area of an sheet of 8x10, using it for a 36 exp roll of 35mm or a roll of 120 will only cause one to use a very small fraction too much...no prob.

 

[ic-racer]

I base my capacities on a nominal 80 in square per roll of film, or four 4x5 sheets or a single 8x10 sheet.

According to the chart posted in #16, it appears the four 4x5" sheets are indeed about 80 in square, but the 35mm roll is more like 85 in square. That is actually more surface area than I expected. I probably won't change anything because, at least for B&W capacities, most all products I have been using since the 1970s are basing capacity on a nominal 80 in square per roll of 35mm film.

[80 square inches of film]...is equivalent to one 8 by 10 inch or four 4 by 5 inch sheet films, one 620 roll film or one 36-exposure roll of 35mm film. Kodak Darkroom Dataguide for Black and White, 1974