AGFA 304 Fixer: Substitution for potassium metabisulfite?

[Barnstable]

I know I'm years late on the topic of Agfa304 fixer but what are the recommended fixing times for its use with 1. resin coated paper and 2. fibre based paper? Thanks in advance.

 

[ags2mikon]

Here let me assist you with cpr on an old thread. I have found that the clearing time with film is about halfway between rapid fix and plain old hypo fix. I have not used it with fiber base papers. It is easy to mix and in dry form keeps forever. I always use a stop bath before and I reduce the sodium metabisulfite by 50%. You can source all the chemicals from pool and spa suppliers and farm suppliers. The Ammonium chloride is used in goat farming.

 

[Rudeofus]

Based in Agfa 304's formula and a few tweaks mostly inspired by PE I crafted a new formula for a neutral quick fixer. I recommend you use that instead of Agfa 304, which has a pretty low shelf life.

 

[ags2mikon]

@Rudeofus, That looks very good. I use the Agfa 304 in my motorhome darkroom because I do not carry liquid chemicals when moving. To many things to go wrong. I mix it when I park and dump it when I leave. I carry it pre measured in small vials / bottles so it takes just a few minutes to mix a batch. But I like your idea and will reformulate before my next trip out. The smell can be obnoxious in a small space.

 

[Rudeofus]

Regarding fixer speed, since this was the original question from @Barnstable :
This will depend on fixer exhaustion and the exact paper you use. I do know, that my neutral quick fixer needs about one minute to clear Tri-X, so I would not expect paper to need longer fixation than two minutes. There are allegedly papers out there with Silver Iodide in their emulsions, so the old adage "paper is much easier to fix than film" may no longer hold. If you want to be sure, make a quick test with selenium toner in some clear spot.