Got the Linhof 4x5 out and did some testing with Tri-x. I want to try some zone portrait photography over the next while. I used a standard reflected meter set at a ASA of 100 this last trip for the Khon Thai portraits. I found most exposures ok but at times they were also off a bit. I want to try to zone the tri-x and use a spot meter over the next while to see if I can improve my exposure and the tonality of my negs. I am unsure of where to place Thai skin on a zone system scale but I guess that will come with experience.
Will do the tests over the next few days (hate testing!) and see if it improves the quality of the negs.
Next trip I also want to try using a reflector in the portraits as Sturges recommended, especially to bring up the light a bit in the faces of people wearing hats.