Mixing of VD solutions to alter contrast

[Sandy King <sanking@CLEMSON.EDU>]

As I noted in an earlier post, a VD sensitizing solution that I 
recently mixed (according to the classic formula), gives images with 
a very long tonal scale (8+ stops, or log 2.4), and this on several 
papers. This tonal scale is really too long for most of my negatives, 
which are developed to a DR of approximately 1.6 for carbon printing.


My question is this. How can I alter the mixture of the original 
sensitizer to reduce the tonal range of the process to 5-6 stops? I 
am assuming that the primary contrast control is the amount of 
tartaric acid in the solution. Is this indeed the case? And if so, 
should I increase or decrease the amount of tartaric acid in the 
sensitizer get more contrast from the process?

Sandy King


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