Odd fixer questions

I saved the diluted Arista Oderless Fixer from my last print session of a few days ago. Planning on another session tomorrow, I just did a clip w/ some ends off my 35mm rolls of film. The diluted fixer from the last session clears the film in 20-30 seconds, but the left over, undiluted stock solution in the bottle takes 2 to 3 times that long to clear the same film.

I'm wondering if I may have accidentally mixed the fixer solution at 1:4 for film instead of 1:7 for paper the other day, and it's still very active? And maybe the 1/2 of a bottle of fixer I just opened a few days ago went a little off because of the air space in the bottle? Lot of maybes here, but it looks like the saved fixer is more than good for tomorrow.

momus said:

... but the left over, undiluted stock solution in the bottle takes 2 to 3 times that long to clear the same film.

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Hi, I'm not exactly sure if you're asking a question, but FYI if you did a clearing test on the original concentrate this doesn't really mean anything. You have to dilute it down a little for it to work.

Air isn’t a problem for fixer, so it’s more likely that you made a dilution mistake, or confused the bottles, or possibly contaminated the slow bottle.

Mr Bill said:

Hi, I'm not exactly sure if you're asking a question, but FYI if you did a clearing test on the original concentrate this doesn't really mean anything. You have to dilute it down a little for it to work.

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What he said.
The water in working fixer is important to the process.

momus said:

I saved the diluted Arista Oderless Fixer from my last print session of a few days ago. Planning on another session tomorrow, I just did a clip w/ some ends off my 35mm rolls of film. The diluted fixer from the last session clears the film in 20-30 seconds, but the left over, undiluted stock solution in the bottle takes 2 to 3 times that long to clear the same film.

I'm wondering if I may have accidentally mixed the fixer solution at 1:4 for film instead of 1:7 for paper the other day, and it's still very active? And maybe the 1/2 of a bottle of fixer I just opened a few days ago went a little off because of the air space in the bottle? Lot of maybes here, but it looks like the saved fixer is more than good for tomorrow.

Click to expand...

A few facts for you to consider before tossing your fix and mixing new:

First, "print-strength" fixer (1+7 or 1+9 depending on the manufacturer) takes longer to clear film (or anything) than "film-strength" fixer. If you're comparing a clip test in film strength fixer with one in print strength fixer later, you're comparing apples and oranges.

Fixer for fiber-base prints (you don't say what kind of paper you use) tolerates much less dissolved silver before fixer capacity is reached than fixer for film or RC paper.

Fixer capacity for prints is best determined by throughput. The manufacturers give recommendations; follow those for the "general" or "commercial" level of print permanence. If you are after optimum permanence for fiber-base paper, you need to either reduce capacity to about 10 8x10s per liter or go to two-bath fixation.

The guideline for clip tests for fixing film is to discard the fixer when the clearing time is 2x that in fresh fix. If you did test the same dilution (the same exact fixer) and the clearing time has more than doubled, I'd certainly not be using it for anything (the reason the clip test is bad for paper fix is that it is not sensitive enough; if your times are 2x, the fix is already past its useful life for prints of any kind).

Bottom line, when in doubt, mix new fix.

Best,

Doremus