View Full Version : Simple Fixer question

David Aimone
2-Feb-2011, 12:30
This is a simple question, but I can't seem to find a direct answer here or in any of the books that I have.

Can/should I use the same fixer for developing film and developing prints? I'd like to start using a 2-bath fixer for both, and I'd prefer to keep just two bottles of fixer going instead of four.



Robert Hughes
2-Feb-2011, 12:39
The fixer for film is typically twice as strong as paper fixer. For instance, Ilford Rapid Fixer is mixed 1:4 for film, 1:10 for paper.

I have re-used film fixer as paper fixer without obvious problem.

Bruce Barlow
2-Feb-2011, 14:50
I use Sprint Rapid Fix 1:4 for both film and paper. 5 min for film, 30 sec for paper. I could dilute more for paper, but I like the short time, so for me, it's worth it.

2-Feb-2011, 14:53
It's commonly suggested to not use the same exact specific bottle of working solution for both film and prints, regardless of dilution. You should have a bottle mixed for film, and one for paper.

I forget why or where I read this, but I believe it may have been from Photo Engineer over at APUG.

(Plus it would be more difficult to figure capacity...)

David Aimone
2-Feb-2011, 15:34
Well I'm definitely looking for a non-hardening fixer for paper, so I may just go separate.

Do most of us use one or two bath fixers. If one bath, which method do you use for determining that the fixer is used enough but not too much? For paper, I've been logging the 8x10 equivalent sheets fixed. The sprint fixer says it can do at least 90 8x10 sheets. My fixer test drops showed cloudiness around half that.

I'm trying to be conservative with fixer, as it's not environmentally sound to dump and hard to dispose of, but I'm also trying to make sure the prints are fixed well enough. That's why I'm considering the two-fixer bath approach.


Mark Sampson
2-Feb-2011, 17:05
To dispose of your used fixer, find a photo lab. There must be one in your home town. They all recover the silver from their fixer and will be happy to take yours. It's possible to recover your own but the small amounts home users generate means that it's usually not cost-effective to do so- and it's kinda smelly to boot.

Sascha Welter
3-Feb-2011, 06:13
I use two fixing baths for film development. Unfortunately I don't have a darkroom for prints now.

As for determining how much to use the fixer, I just go with the rule of thumb for my fixer (Tetenal Vario Fix), that says ~ 10 films per liter (8x10 or 120 or 135 films, so 40 films 4x5"), then I remove Fix A / use Fix B as the new Fix A / use fresh solution for Fix B. I check the "clearing" time of the negatives to make sure I'm not totally out and also to know how long to fix.

The best information about fixing I have found on a German site from a Mr. Wollstein, unfortunately it's only in German:
How much to utilize fix solutions: http://www.schwarzweiss-magazin.de/swmag_wollstein_09.htm
Fixing and clearing: http://www.schwarzweiss-magazin.de/swmag_wollstein_02.htm
(original frameset with all articles: http://www.schwarzweiss-magazin.de/swmag_frame_wollstein.htm )

Both articles suggest two-bath fixing, on a very logical basis.

There's also something about not using the same fix baths for paper and films, mainly having to do with the amount of silver being much different (more in paper) and films containing something called Jodid.

Doremus Scudder
3-Feb-2011, 09:38

No question about fixers is simple :-)

I'll try to give you a concise answer to your questions.

First, it is common practice not to use the same fixer for film and paper. Modern films contain a lot of silver iodide (the Jodid from the German site), which exhausts the fixer faster and can build up a lot of by-products not good for paper. Plus, it is a pain to calculate capacity when using the same fix for both. I would recommend against it.

As for storing a lot of fixer: I try to mix only what I can use in a short time, which eliminates having a lot of bottles of partly-used fixer around. Save up your film to do in batches and then mix just what you need for the two-bath method once through, i.e., to the point where you would discard bath 1 and replace it with bath 2. Then, discard bath one and save bath 2. Next time you fix, you can use the stored fixer as bath 1 and mix a fresh bath 2. When in doubt, discard the fix; it's better be sure than to underfix. This technique works for both film and paper.

By the way, you can use the more dilute "paper strength" fixer for film, it just takes longer and has a smaller capacity.

A word about capacity testing: For film it is easy. Do a clip test to find the clearing time for your film in fresh fix. I use double that time plus 10-20% in each fixing bath for film. Some will chime in that this is overkill, but I think not, plus with film, one can overfix a bit with no ill effects. Clip-test your first bath after each batch run through it; discard it when the clearing time is double that for the same film in fresh fix.

For prints, things are a bit more complicated. You should try to keep fixing times to the minimum needed to ensure adequate fixing. Keeping your fixer fresh and not overusing it is the key here. I use the manufacturers' recommendations and two-bath fixing. When the recommended number of prints have been through the fix, discard bath one and replace it with bath two. If there is any question, underuse your fixer; it's relatively cheap and the prints are important. Keep to the recommended time as well, with a 15 second drain between fixing baths as well (you get even better fixing if you rinse between baths). If you tone, you can use a work-flow like mine. Fix the prints in fix one, wash and dry. Choose the prints you want to tone, and tone them later in a toning session. Soak the prints, give them fix 2 and then tone. Run only the same recommended number of prints through this bath, and only prints that have had the first fix. You can then save this fix to serve as bath one at a later printing session if you like (though I always toss mine).

The only way to really know how well your fixing is going with paper is to do testing on fixed prints. There are both residual silver and residual thiosulfate (fixer) tests easily available. The former tests your fixing, the latter your washing. It is worth it to get the solutions, mix them up and test your process. I run a blank sheet of paper through the first and second fix as the last print, wash it and test it. If it passes, I know the prints ahead of it are fixed and washed adequately. This only needs to be done to test an unknown process and then occasionally to check it. You can get solutions from the Photographer's Formulary and other places.

As far as discarding fixer goes: I like to take mine to a photo lab if possible. In my area, however, their are no longer any good possibilities to do this, so I collect it in 5-gallon containers and run them to the hazmat collection point once a year. Usually I just have a couple of containers; ten gallons of fixer does a lot.

Hope this helps,

Doremus Scudder