Quoted By:
DIY fixer actual useful post.
Ingredients:
250g Sodium Thiosulfate (also spelled Thiosulphate) Na2S2O3 (pentahydrate) (Na2S2O3•5H2O)
45g Sodium Sulfite
Distilled (don’t skimp out on this) water up to 1l
Instructions:
Fill desired container with ~800ml distilled water.
Add 250g of Sodium Thiosulfate. Be surprised the bottle gets colder. Unlike NaOH, dissolving hypo in water requires energy and lowers the solution’s temperature. Mix till it all dissolves and warm it up to room temperature.
Add 45g of Sodium Sulfite. Mix till it dissolves, top off the solution up to 1l with remaining distilled water.
Bravo, you’ve just done did what makes up 70% of the price of store-bought hypo fixer.
So now some stats. The stuff’s HIGHLY reuseable, at least 10 rolls on one batch (with, obviously, increasing fixing time, eventually) unless you fix underexposed rolls of black people at night /w no flash. It’s a slow-working fixer, none of that ammonia-boosted rapid fixer stuff. 7 minutes at 20C with constant agitation is a nice safety margin overkill. It keeps at least 8 months (experiment pending) and you can just make a batch as big as you need for the time. That’s the beauty. Stuff’s immortal in raw ingredient form until you mix it.
