Actually Phil, I consider pt/pd the first VC process ever. You can vary the contrast, and now with with Sodium platinate even to a greater degree than before. IMO is best to shoot for a perfect negative and then use the alternatives to fine tune. The problem with the BTZS is that it is a very simple method that requires to read a book that can be boring to read and follow. In my case, since I have stated using the BTZS I have done far less testing than I did with the ZS. Also the testing is far easier than the one for the ZS.
Originally Posted by DrPhil