Fixers residue?

Hello,
I usally use Photographers Formulary TF4 fixer for my film but I switched over to Ilford's Rapid fix because I had noticed that my film was drying with gritty scum on it. The Ilford fixer I never had a problem with and I don't now.
I processed two rolls and fixed them in the different fixers and washed them together and still the TF4 roll had this grit.
Has any of you experienced this from TF4 or is it just me?
Just wondering?

this looks more like a washing issue than a fixer issue.
How are you washing after fixing?
Have you considered using a last rinse using distilled water?

Both rolls were washed together in a roll film washer. The Ilford came clean and the TF4 didn't? I used a heavy filter system for washing.

Maybe save the T4 for street stuff, where you want that gritty look?

I've had liquid-concentrate fixer that came out of solution and had tiny crystals in it after being exposed to very cold temps. As the crystals didn't seem to want to re-dissolve, I just filtered them out. Is it possible that something like this is occurring with your T4, Robert?

I guess that could be. Its not too cold in the darkoom. But I'll do the filtering of the fixer to see any difference.
Thanks
R

Are you mixing your Photoflow ahead of time or when you use it? I have found when Photoflow is mixed ahead of time is sometimes leaves residue on the film. This may be what you are experiencing. I usual just add about 1 teaspoon of unmixed Photoflow to my 16 oz tank filled with filtered or distilled water right when I want to photoflow the film.

Robert8x10 said:

I processed two rolls and fixed them in the different
fixers and washed them together and still the TF4
roll had this grit. Has any of you experienced
this from TF4 or is it just me?

Click to expand...

There is one BIG difference twixt TF-4 and Ilford's
Rapid Fix; ph, PH! Ilford's runs 5.5 and TF-4's perhaps
as high as 10.5. I don't use TF-4 and no one has yet
answered my question; what is TF-4's ph?? Whatever
it's exact ph it is surely very alkaline.

It may be just your problem. How is your water?
Prepare a TF-4 with distilled water and be sure your
FIRST wash is with distilled water. Better, use only
distilled, with fixer and all washes.

Although the sodium and ammonium salts of
the silver thiosulfate complex are soluble there is
evidence that other elements, impurities, in water
can form insoluble complexes which can precipitate
on or with in the emulsion. If there is any question
of the water's purity, at a minimum, the FIRST
wash should be distilled water.

If that's not your problem, you're guess is as
good as mine. At least for now. Dan

dancqu said:

..............and no one has yet
answered my question; what is TF-4's ph?? Whatever
it's exact ph it is surely very alkaline................

Click to expand...

In The Darkroom Cookbook, 2nd edition, it is stated that TF-4 is slightly less alkaline than TF-3, for which the formula is given. TF-3 has ammonium thiosulphate, sodium sulphite and a little sodium metaborate. It doesn't look like a formula that would give very high pH.

The instructions for TF-4 say "shake before dilution" which I suppose suggests that there is some indissolved material in there. They also specify distilled water, I think. Maybe something has happened to make Robert's diluted TF-4 not dissolve properly, and particles are settling on the film.

I use inversion agitation, but I agitate constantly while fixing. I found that it cured a problem that I had with particles on the negs. I surmised that keeping whatever particles that there might be in constant motion would stop them sticking on the emulsion. I don't know if it's true, but I've been doing it like this for a long time.