fixer capacity for 8x10 film

[Mike Troxell]

Most manufacturers fixer capacity is stated in how many 35mm rolls of film can be fixed per volume. If you are developing 8x10 sheet film and the manufacturer states that 1 liter of fixer is good for 15 rolls of 35mm, how many sheets of 8x10 film could you assume the fixer is capable of fixing before nearing exhaustion? What is the film surface correlation between 35mm and 8x10?

[Conrad Hoffman]

I've never checked it, but they usually talk in terms of 1 36exp roll being 80 square inches, same as a sheet of 8x10 film!

[Gem Singer]

Hi Mike,

According to Iford's website (www.ilford.com), one roll of 36 exposure 35mm film and one roll of 120 film is, approximately, equal to, one sheet of 8X10 film or four sheets of 4X5 film, in surface area.

However, tabular grain films (T-Max, Delta,etc.) require more fixer than conventional grained films. Therefore, they exaust fixer at a rapid rate, and reach maximum capacity earlier.

[Mike Troxell]

Thanks for the replies. That should help me keep track of fixer capacity.