Cyanotype / ZnSO4 development

REF #85

Potassium Ferricyanid K3[Fe(CN)6] sol. 8%

Ferric Ammonium Citrate [NH4]{y}[Fe{x}(C6H4O7)] sol. 20%

Zinc sulfate ZnSO4.7H2O sol. 0.2%

1. Make a basic cyanotype (6 mins), but do not wash with water.
2. ZnSO₄ bath for 30 seconds.
3. Wash three times for 30 seconds each time.