TONING 



455 



papers may not all work the same, the difference in result will not be very great. 

 With a few experiments in exposure and developing time, it is possible to arrive at the 

 tone desired. 



Adurol Formula 



Adurol 6 . 8 g. 97 gr. 



Hydroquinone 6 . 8 g. 97 gr. 



Sodium sulphite (anhydrous) 62 . 4 g. 2 oz., 85 gr. 



Sodium carbonate (monohydrated) 54.4 g. l^i oz., 60 gr. 



Potassium bromide . 7 g. 11 gr. 



Water 1000 cc. 32 oz. 



Table I. — Dilution, Exposure Time, Etc., for the Adurol Formula 



If the Adurol in the above formula is replaced by glycine and the amount of 

 sodium carbonate increased, we get a similar range of tones. 



Glycine Formula 



Glycine 6.8 g. 97 gr. 



Hydroquinone 6 . 8 g. 97 gr. 



Sodium sulphite (anhydrous) 62 . 4 g. 2 oz. 85 gr. 



Sodium carbonate (monohydrated) 88.4 g. 3 oz. 50 gr. 



Potassium bromide . 7 g. 1 1 gr. 



Water 1000 cc. 32 oz. 



Table II. — Dilution, Exposure Time, Etc., for the Glycine Formula 



As tones produced by direct development are not always those that may be desired 

 and because the results are not always easily reproduced, except through very strict 

 attention to small details, methods which convert the silver image to some other com- 

 pound possessing the color desired are used. The simplest of these methods are 

 those known as sulphide toners. 



Sulphide Toning Processes. — The sulphide processes produce sepia tones by con- 

 verting the silver image into insoluble silver sulphide. Prints toned by these methods 



