Quote Originally Posted by Photo Engineer View Post
'ello mate. You are using British or Canadian spelling of COLOR Mark.
So, there is an unknown variable in these tests that cause a problem! Before you go on, you must identify that variable. Find out if it affects all films or just this one batch etc.... PE
First, Kirk: Thanks for the suggestion about a two-bath method of fixing. For me, fixer costs almost nothing compared to rolls of film, so I'll probably simply replace my fixer much more often.

@PE: Does my personality have color or colour? The apug spell-checker red-marks American spellings as wrong, and since British English is the international standard, I figured I should spell things that way.

There's another variable I neglected to mention: The plastic lid for the SS tanks had a orange-brownish residue on them which I noticed after the bad TMY rolls, and which I cleaned off. My beaker dedicated solely to fixer also has a slight orange colour-cast, so the TF-4 fixer leaves a bit of insoluble residue. But the amount is so small, and the prewash removed some magenta dye (unlike later steps) that I doubt this residue was the cause of failures. Note that I wash film with the lid on, so this residue survived all that washing.

I discarded the old fixer, so I can't reverse that change.

Today, I tried a roll of TMY2 with cool liquids for everything but developer. It made no difference (everything worked fine).

Listing the changes:
* Insoluble residue - exceedingly unlikely to affect anything.
* Temperature - had no effect.
* Old TF-4 fixer - that must be the cause!

I suspect that well-used TF-4 accumulates a chemical that prevents dissolution of the magenta dye. In addition, it seems to do some bleaching. "Well-used" meant 51 rolls in 1.5 litres, including about 20 test-strips which would dilute it a little.

Your opinions about this? I wish I'd kept the old fixer.

Mark Overton