I have the results of my first test roll. As I said before I shoot a roll of 35 mm HP5+, rated 125 asa, developed 11:30 m in D76 1+1. The net densities are:
zone I 0.125; zone V 0.575; zone VIII 0.930. Taking as reference the information from the book "The Negative" of Ansel Adams give for what he deliberately put in quotation marks as "normal" to print in a difusion enlarger, the results are ok for zone I and V, but low for zone VIII, that most be between 1.25 and 1.35.
My conclusion is that I'm exposing correctly but I need to increase the developing time.
So I have to make another test.