Hypo as BW fixer

Hypo (sodium thiosulfate) is cheap and easily available. It costs around Rs.100 per half kg. Hypo comes in crystalline form; it looks like large transclucent grains of rice.

I use a film roll canister to measure out the crystals. A little over one measure added to 300ml of warm water is the mixing ratio I use. It takes around 5mins to fix using this solution. This solution can be reused.

There is a simple way to find out the time required for fixing. Drop a small piece of film leader (which you cut out when loading the film reel) into the hypo solution. Start the stopwatch. Check the film at the end of every minute. Note down the number of minutes required to make the film transparent. Double this time. This is the number of minutes required to fix your film.