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This formula was invented by russian photo-chemist and engineer V.Y. Mikhailov (Emulsion Laboratory, NIKFI) and published in 1938. It was derived and improoved from Steigmann formulas the same years.
High contrast silver chloride emulsion (Mikhailov, 1938).
Solution A:
Water - 3000 ml
Sodium chloride - 64.2 g
Cadmium chloride (hydrate?) - 3 g
Gelatin - 80 g
Blood albumin (2% solution) - 12 ml
Solution B:
Water - 750 ml
Silver nitrate - 100 g
Heat both solutions to 70C, mix rapidly and cool to 60C immediately. Ripen at this temperature for 20 min. Add 330 g gelatin and 50 ml 2% albumin and ripen more for 10 min. Add 800 ml water (60C) and finally ripen for 10 min. Cool to the coating temperature and coat it on baritaged paper ASAP.
Coating finals - common ones.
Loading - 150 ml per 1 m2 (ca. 1.9 g silver metal per 1 m2).
Paper properties:
Speed - 180 - 300*
Gamma (1 min developing) - 3.2 - 4.0
Fog density (1 min developing) - 0.01 - 0.03
* speed was calculated from exposure H(g) for minimal gradient g=0.2 as S = 10000/H.
Emulsion can be stabilized by conc. hydrochloric acid (5 ml per 1 L) addition - added after 30 min of ripening.
High contrast silver chloride emulsion (Mikhailov, 1938).
Solution A:
Water - 3000 ml
Sodium chloride - 64.2 g
Cadmium chloride (hydrate?) - 3 g
Gelatin - 80 g
Blood albumin (2% solution) - 12 ml
Solution B:
Water - 750 ml
Silver nitrate - 100 g
Heat both solutions to 70C, mix rapidly and cool to 60C immediately. Ripen at this temperature for 20 min. Add 330 g gelatin and 50 ml 2% albumin and ripen more for 10 min. Add 800 ml water (60C) and finally ripen for 10 min. Cool to the coating temperature and coat it on baritaged paper ASAP.
Coating finals - common ones.
Loading - 150 ml per 1 m2 (ca. 1.9 g silver metal per 1 m2).
Paper properties:
Speed - 180 - 300*
Gamma (1 min developing) - 3.2 - 4.0
Fog density (1 min developing) - 0.01 - 0.03
* speed was calculated from exposure H(g) for minimal gradient g=0.2 as S = 10000/H.
Emulsion can be stabilized by conc. hydrochloric acid (5 ml per 1 L) addition - added after 30 min of ripening.