Quote Originally Posted by Stuggi View Post
Are you talking Ilford Rapid Fix? That trick
would save me a lot of money... ^^
I used PF's 60% ammonium thiosulfate concentrate
with nothing added. A liter bottle was split to 1/4 liters
then a 1/4 liter to 1/16 liters. One of those was then split
to 1/64s and later, after some aging, to 1/48s liter.
I shoot only a few rolls a year so do more splits
than some would do.

Any off the shelf rapid concentrate should run 60%
give or take some little. Test a roll with 20ml. Constant
agitation the first minute and each minute there after a
few inversions. Allow 5 or 6 minutes then check for clear.
You'll fine tune the time after a few rolls.

Be sure the film is clear + prior to dumping the fix. There is
no checking the fixer for twice clearing time. Although the
fixer is very little loaded with silver on a volumetric basis
it should be NEARLY exhausted. Tests used unexposed
rolls. Unexposed places the entire silver load in the
fixer. So some excess fixer. I've not tested with
iodized films.

Low volume or high, fresh fix, no testing needed, no
rebottling. Dan