Color fixer dilution for B&W

I recently bought 10l tetenal color fixer conc. I know it's perfectly ok for BW and it was way cheaper then any other fixer I can get here.

Label says its to be used diluted 1+5 (or 1+4) for c41, e6 and ra4. I suppose its also right dilution for BW. But I know that BW fixers often have two dilutions - lower for higher speed and higher for economy.

Does it apply to color fixer used for BW? Is testing higher with a piece of fogged film enough to make sure diluted fixer is ok?

I use agfa FX Universal which is also a colour fixer. Its an akaline fixer but only slightly and therefore to kill development quickly you should always use a stop bath. For film I use 1+3 and for prints 1+7 to 1+9.

I think all colour fixers are alkaline because acid fixer would destroy the colour dyes.

I always use stop bath anyway.

What is dilution for color processes of your fixer?

Actually tetenal RA4 kit recommends acid stop bath. The acidity issue might be more complicated.

Use the same dilution for B&W film as suggested for color film.

The difference is in capacity due to silver coated in color films. So, the fixer will act at the same rate but have about 2x the capacity all other things being equal.

PE

I've been using Kodak's Flexicolor C-41 fixer at the recommended dilution rate for film and it seems to go on almost forever. I double the dilution for paper, and have tested that dilution with film. It's action is slower and the capacity is less, but it still works as it should. The dilution ratio and timing isn't all that critical for fixers as long as there is fixing capacity enough to do the job and the process is allowed to run to completion. Two to three times the clearing time is sufficiently accurate timing.

Domin said:

I always use stop bath anyway.

What is dilution for color processes of your fixer?

Actually tetenal RA4 kit recommends acid stop bath. The acidity issue might be more complicated.

Click to expand...

I don't know what the dilution for colour is. FX Universal is used by mini labs for machine processing. But Agfa long ago said it could be used for B+W but recommended their specialist B+W fixers instead ( a lot more expensive ).