Fixer longevity : how many rolls/prints?

[PhotoJim]

Also worth stressing that if you do put your fixer down the sink, the more 'used' it is the worse it definitely is for the environment. Another reason, apart from archival reasons, I don't use it to exhaustion. Although one of my NY res's might be to dispose of all my chems (apart from developer) via the Council hazardous waste route...

I'm going to fight with your logic. I am of the opinion that 1 unit of fixer with .1 units of silver in it is better for the environment than 100 units of fixer with .1 units of silver. The total silver exposure to the environment is the same (you are shooting the same amount of film or processing the same number of prints whether you reuse your fixer or not), but you are discarding more fixer which is itself a pollutant.

Certainly fixer with strong amounts of silver in it will be bad for the environment, but diluting the silver with fixer isn't exactly helping. You're just discarding more pollutants.

 

[Lee Shively]

I'm no expert on any of this. Both Ilford and Kodak give similar exhaustion rates for their fixers and these are undoubtedly conservative figures due to many unknown factors once the product is in the hands of the consumer. Other brands probably have similar exhaustion rates but I would consider dumping them a little more often than either Ilford or Kodak unless there are manufacturer's recommendations available that state otherwise.

Personally, I use film strength, non-hardening rapid fixer as a two-bath solution for prints. With the initial chemicals, I dump the first bath a little more often than is recommended and move the second bath up to number one. This rotation keeps the second bath fresh and the first bath used to near exhaustion. With film fixer, I test the chemical with a film leader or dump the fixer after six months or so. The amount of film I shoot and process can vary considerably over time. Sometimes I shoot dozens of rolls in a month and sometimes I shoot nothing for several months.

As for the one-shot fixer idea, I make no sense of the notion for dumping out perfectly good chemicals, especially when based on an environmental/conservationist argument. It's wasteful and it simply means the consumption of more chemicals and more chemicals being dumped into the environment in the long run.

 

[Phillip P. Dimor]

I use naaco fixer test or whatever it's called. One drop into a bit of fixer will tell you if it's good to go. I had developed about 40 sheets of 4x5 tri-x no problem but went to develop a roll of 120 tmax and it didn't clear.

 

[catem]

As for the one-shot fixer idea, I make no sense of the notion for dumping out perfectly good chemicals, especially when based on an environmental/conservationist argument. It's wasteful and it simply means the consumption of more chemicals and more chemicals being dumped into the environment in the long run.

I don't dump 'perfectly good chemicals' - only chemicals I can no longer rely on to do the job I want

I don't want to overplay the environmental issue overmuch as most sewer systems are able to cope with the amounts of silver dumped from home darkrooms- when you think of household chemicals some of those are worse. HOWEVER with fixer it is the sludge that forms that though unlikely to cause harm may potentially cause a degree of harm in larger quantities. As I understand it, this is lessened if you release less exhausted fixer in greater dilution (achievable by using more running water as you dispose). It may be small difference in the larger scheme of things but on the other hand every little helps and it makes me feel better.

 

[Paul Howell]

I use naaco fixer test or whatever it's called. One drop into a bit of fixer will tell you if it's good to go. I had developed about 40 sheets of 4x5 tri-x no problem but went to develop a roll of 120 tmax and it didn't clear.

I use Edwal Hypo check at the start and at the finish of large batch processing such as 4x5 in tanks. With Edwal I can tell when the fix is about finished, the check with start to cloud up then clear after a second or two, thats when I dump and fix fresh.

 

[stillsilver]

hello,
I use fresh fixer for my film because that is the one thing I can't redo. I also use fresh fixer for my 2nd fix bath when archival printing. I use used fixer for my 1st bath or when only fixing proof or work prints. I use the exating scince of 'guesstimation' to determine when the fix is exhausted. My methods may not be the best, but I don't like cutting corners when it comes to long term things (negatives, hanging prints).

 

[dancqu]

Dan
Please take a look at the link below;
http://www.uos.harvard.edu/ehs/silver_recovery.shtml

Now, as this is an article on silver recovery from darkroom fixers,
and it also warns of the dangers of discharging used fixer in to
the enviroment, I can only assume that there is a silver
content in used fixer.
At what point a fixer reaches a point where as it becomes
a hazard does not concern me. The fact is that used fixer will
have silver particles, or what ever word you wish to use, in it.
As this silver is capable of attaching itself to surfaces, in
this instance it would be the soft emulsion of my film,
I have chosen that during my own development
routine I do not wish to subject my film to
such a risk, however small.

Yes, as this post proves there are many APUGers re-using
fixer with no complaint, and they are very happy with their
results, as I am with mine. So there is no reason for any of
us to change our development routines. Regards Stoo

That article has to do with the specific means by which the
silver may be extracted from a used fixer solution. The means
detailed uses an active metal to reduce the silver thereby
plating the silver out of solution. Electrolytic means are
also used.

Again; off hand I can think of nothing we might have around
the darkroom which would cause the precipitation of metallic
silver from within a fixer solution. Dan