This developer originated in a discussion with Jorge G. some months ago. Jorge indicated that he thought a good paper developer could be based on pyro. He gave me some idea of what to try and I took
the formulation from that point. It arose out of the realization that while Amidol was an excellent developer the cost was excessive.
I have found that, in this formulation, the developer is quite active, with emergence times on the order of 14 seconds, compared to 45 seconds in Dektol on Seagull VCFB. The emergence time when
compared to Amidol (Michael A. Smith formula) is very nearly the same and possibly slightly less with the pyro formulation. The papers I have tested this developer with (Seagull VCFB, Azo, and J&C
Polywarmtone Classic) have all shown about a one stop gain in paper speed compared to development in Dektol.
The formula provides flexibility in the ratio of pyrogallol to catechol, which may be of some importance for those who work with graded materials such as Azo. For instance I have mixed it with
11 gm of pyrogallol and no catechol and observed an increase in dmax as measured by my Xrite 310 TR. With the straight pyrogallol formulation the paper takes more of a set (probably due to hardening of the emulsion
caused by pyro tanning). By going to catechol at 16 gm and no pyrogallol the formulation becomes very soft. The formulation I have provided here gives nice convincing blacks, overall good tonal separation, and very
clean highlights. Additionally, the formula as published allows for good toning with Seagull VCFB. I will attach three images that I have developed in this formula which at this time I am naming Pyro Plus Paper