Solution A

Water - 1 fl. oz. - 30mL - 1 1/4 fl. oz.
Potassium Ferricyanide - 15 grains - x g - 18 grains


Solution B

Water - 32 U.S. fl. oz. - 1 L - 40 Imp. fl. oz.
Sodium Thiosulphate (Hypo) - 1 oz. avdp. - 30g - 1 3/16 oz. avdp.

Use within 5 min. of mixing, or use the longer-keeping two solution version:



[Solution A

Potassium Ferricyanide - 1/4 oz. avdp. - 7.5g - 5/8 oz. avdp.
Water to make - 32 U.S. fl. oz. - 1L - 40 Imp. fl. oz.

Treat neg.'s in soln. A with uniform agitation 1-4 min. at 65-70 deg. F (17-20 deg. C) depending on the desired amount of reduction.

Solution B

Sodium Thiosulphate (Hypo) - 6 3/4 oz. avdp. - 202.25g - 8 1/8 oz. avdp.
Water to make - 32 U.S. fl. oz. - 1L - 40 Imp. fl. oz.

Immerse negatives in soln. B for five minutes after treatment in soln. A; then wash thoroughly.]

Formula given in U.S. measurements. Metrics accurate to within 250mg. Imperial measurements accurate to within 1/16 (fl.) oz. avdp., or 1 grain with smaller quantities of mass. Liquid measurements rounded proportionally, weights rounded based on 1.2 Imp. Qt. to 1 U.S. Qt. in terms of mass.