Meaning of sodium thiosulphate in English:

sodium thiosulphate


(also sodium thiosulfate)
mass noun
  • A white soluble compound used in photography as a fixer to dissolve unchanged silver halides.

    Also called hypo

    Chemical formula: Na₂S₂O₃

    ‘Excess silver is removed by sodium thiosulfate.’
    • ‘One fixative used commonly is sodium thiosulfate.’
    • ‘The process involves adding a 10% solution of sodium thiosulfate to the second developer.’
    • ‘Salted paper is usually fixed in a 10% solution of hypo (100 grams of sodium thiosulfate in 1 liter of water) for 10 minutes.’
    • ‘I should note that the traditional method of fixing prints in a sodium thiosulfate solution for 5 to 10 minutes is perfectly acceptable, so long as fixing and washing times are adequate.’