Yup. It looks similar. I use bicarbonate because it's extremely cheap and it's available in very pure form from any supermarket (it's so cheap and clean, that I also use it as a source of sodium carbonate for developers ). I guess any mild base, like sodium metaborate, or borax, would work just as well, but I just find bicarbonate more convenient.Here's a formula for TF-2 Alkaline Fixer from The Film Developing Cookbook. It looks a lot like Vlad's formula.
Water 750ml
Sodium Thiosulfate 250 g
Sodium Sulfite anhydrous 15 g
Sodium Metaborate 10 g
Water to make 1 L
The thread is two years old, and at that time I was just starting to mix my own fixer and wasn't yet sure about the formula. I used 240g of crystallized thiosulfate because I had found that amount recommended in books and on the internet. The formula called for 160g anhydrous or 240g pentahydrate. So I took the 240 for granted. However, the pentahydrate equivalent of 160g anhydrous is not 240g, but 250g. One mole of thiosulfate is 158g anhydrous or 248g pentahydrate.
So I'm now using 250g of thiosulfate, not 240g as I said two years ago.
In practice there's probably no difference, anyway.
Whether 15g of sulfite would be enough, I don't know. 30g seems to work for me, but who knows, maybe I could get away with less. I don't know how to calculate the minimum amount of sulfite required to preserve a liter of fixer for a long enough time. We need a chemist's help. Ole?
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