Thiourea Toners

Name Thiourea Thio-Carb
Bleaching Solution
Potassium Ferricynide 22 g 50 g 6 g 50 g 50 g
Potassium Bromide   --- 10 g   --- 25 g 50 g
Sodium Carbonate   --- 20 g   ---   ---   ---
Sodium Chloride 35 g   ---   ---   ---   ---
Nitric acid 15 ml   ---   ---   ---   ---
Ammonia (10% solution)   ---   --- 15 ml   ---   ---
Water to make 1000 ml 1000 ml 1000 ml 1000 ml 1000 ml
Toning Solution
General Tone Deep-Brown Purple-Brown Cold-Brown Brown Warm Brown Yellow-Brown Cold-Brown Dark-Brown Brown
Thiourea 3 g 1 g 2 g 3 g 4 g 5 g 2 g 2 g 2 g
Sodium Hydroxide 6 g 10 g 8 g 6 g 4 g 2 g   ---   ---   ---
Sodium Carbonate   ---   ---   ---   ---   ---   --- 100 g 100 g 100 g
Water to make 1000 ml 1000 ml 1000 ml 1000 ml 1000 ml 1000 ml 1000 ml 1000 ml 1000 ml

NOTE:
The ratio of potassium ferricyanide to potassium bromide also has an affect on the final image tone. Increasing the amount of potassium bromide will warm the resulting on most print emulsions. Split-toning is possible with short immersion times in the reducing bath.

REFERENCE:
Thiourea Toner, Kit No. 06-0045,
Thiourea Print Toner, Kit No. 06-0065, Photographers' Formulary (800-922-5255),
Darkroom Techiques for Landscape Photography, Eddie Ephraums, p.159,
Classic Toning Methods, Peter Hughes (Reichelt), Mastering Black-and-White Photography, p.49,
Photo-Lab Index, Supplement No. 193, p.123,
The Photographer's Toning Book, Tim Rudman, p. 32.

Return to Jack's Photographic and Chemistry Site

Revised: Apr. 30, 2003