MEANS:Light: Photo: Gum: pg1

Gum bichromate

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Recipe I

Gum:
powdered gum arabic (350 g)
hot water to make 1 liter (add powdered water color pigment, according to the image color and density required Sensitizer:

potassium dichromate crystals (50 g)
Warm water (500 ML) - store sensitizer in dark tinted container

Mix 2 parts gum to 1 part sensitizer just prior to use

Recipe II

Part A
20mL Prepared Gum Arabic Solution (14 degree Baume liquid solution from fine art or graphic arts supplier)
2-3g tube water color with high density of pigment (i.e. Winsor&Newton, MaimeriBlu)

Part B
13g Potassium dichromate or 25g ammonium or sodium dichromate
80mL distilled water at 125 degrees F Approx.
20mL distilled water at room temp to make 100mL solution.