I second the recommendation to read Fred Picker's "Zone VI Workshop."
I also recommend Carson Graves' "The Zone System for 35mm Photographers." (Be careful - the edition I have has a misprint where it's listing f/stop - shutter speed combinations. I can't remember where the error is, though)
As for exposing for Zone III shadows, not all shadows are that dark. And also, you can expose for half or 1/3 zones too - Zone IV-1/2 for example.
Last edited by Kisatchie; 05-08-2011 at 01:21 PM. Click to view previous post history.