Another fixer related question

[colrehogan]

I was reading the fact sheet for Ilford's Rapid Fixer and it lists the capacity for the fixer when using with film only for 35 mm. What is it for sheet film usage? I'm shooting 8x10 mostly. Can we use the numbers given for 8x10 paper as a guide? Thanks.

Diane

 

[Paul Sorensen]

I was reading the fact sheet for Ilford's Rapid Fixer and it lists the capacity for the fixer when using with film only for 35 mm. What is it for sheet film usage? I'm shooting 8x10 mostly. Can we use the numbers given for 8x10 paper as a guide? Thanks.

Diane

I wouldn't necessarily use 8X10 paper numbers. For one thing, they may be at different dilutions, for another, you don't know that the density of silver on the paper is the same as the film.

Generally, the rule of thumb I hear is that 1 roll 35mm = 1 roll 120 = 4 sheets 4X5 = 1 sheet 8X10. If you think about it, that makes sense since they all take roughly one 8X10 sheet of negative sleeves to store.

 

[Ryuji]

I was reading the fact sheet for Ilford's Rapid Fixer and it lists the capacity for the fixer when using with film only for 35 mm. What is it for sheet film usage? I'm shooting 8x10 mostly. Can we use the numbers given for 8x10 paper as a guide? Thanks.

You should use the figures for film and use equivalent square inch to convert the number. In case of 35mm and 8x10, both are about 80 square inches, so you can fix the same number of 8x10 sheet films as the number specified for 35mm films.

Don't take the paper capacity and apply it to film emulsions. Emulsions used in paper and film are different, and also other factors in fixing and washing are different.

 

[Gerald Koch]

For calculation of capacity, 1 sheet of 8x10 film is considered to be equal to 1 roll of 36 exp 35mm which is equal to 1 roll of 120. Not completely accurate but close enough considering the uncertainties in other factors.

 

[colrehogan]

Oh, ok. That's pretty much what I had been doing. Thanks.

Diane