Godefroy's Process 1858


Float the paper upon the following solution for three minutes and hang it

up to dry:



Uranium nitrate 30 to 60 parts

Silver nitrate 8 parts

Water 100 parts



(39)



The sensitiveness increases in proportion to the quantity of uranium

nitrate. With the above formula the paper can be exposed in the camera,

or, for printing, under a negative cliche.



In printing an exposure of five seconds in diffused light gives an image

perfectly visible, and a grayish black tone; ten seconds gives a vigorous

image almost of a black color; in from fifteen to twenty seconds the image

is very strong, with the color of an engraving. In sunshine the action is

necessarily much more rapid.



The impression is developed by immersion in



Ferrous sulphate 8 parts

Tartaric acid 4 parts

Sulphuric acid 1 part

Water 100 parts



The image is rapidly developed. It is fixed by washing in water.



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