The Usage of Hardening Fixer

[RoboRepublic]

Hi folks,
I picked up some hardening fixer to try and fix up my soft negatives and I was curious- if I am to mix a gallon of this stuff- can I continue to use it as a regular fixer for my negatives? I've only used illford rapid fix for the past three years and I don't have any experience with hardening fixative!
Thanks!

 

[MattKing]

Yes.
You need to be sure you wash the film well - hardening fixer will result in washing being less efficient.
I'd extend my temperature controlled wash longer and probably use a wash aid like HCA as well.

 

[RoboRepublic]

Thanks Matt, what can I expect from poor washing after the usage of a hardening fixer?

 

[Doremus Scudder]

The Legacy Pro product that you have is likely the same, or very similar to, the Kodak F-6 formula (or maybe F-5 or F-7). In any case it is the alum (usually potassium aluminum sulfate) in the mix that does the hardening. This was industry "standard" for decades before rapid fixers became common and emulsions were pre-hardened.

This is also a "conventional" sodium thiosulfate fixer, so fixing times will be in the 5-10 minute range. Since it's hardening, washing times will be slightly longer. For fiber-base papers, I'd try to use a non-hardening fixer, but you can use this too, just make sure you use a wash aid and wash extra long.

Doremus

 

[MattKing]

Thanks Matt, what can I expect from poor washing after the usage of a hardening fixer?

It isn't that the washing is poor.
It is that hardened emulsion gelatin holds on to fixer more tenaciously, so you need to wash longer and/or use a wash aid to get that fixer out afterwards.
I still would like to know though what is happening to cause your films to require hardening fixer though. The films listed in your other thread describing your problems with soft emulsion are all or mostly well pre-hardened, and would normally not require additional hardening, unless they have been subjected to something unusual.
The only reason I use hardener now is with materials that I have toned, which tends to soften emulsion.

 

[Bronson Dugnutt]

It isn't that the washing is poor.
It is that hardened emulsion gelatin holds on to fixer more tenaciously, so you need to wash longer and/or use a wash aid to get that fixer out afterwards.
I still would like to know though what is happening to cause your films to require hardening fixer though. The films listed in your other thread describing your problems with soft emulsion are all or mostly well pre-hardened, and would normally not require additional hardening, unless they have been subjected to something unusual.
The only reason I use hardener now is with materials that I have toned, which tends to soften emulsion.

This, +1000. The speed you gain in rapid fixing is balanced out by longer wash times. TNP did a good presentation on the topic.