The Zone System is really fairly simple to understand. The difficulty is the comprehensiveness the approach requires. Like everyone else, I would recommend Ansel Adams' "The Negative" as a great way to start. Tim
This is going to read long-ish, but I'll do it.
Tim, I do agree! A studious and enquiring mind is a valuable addition to the approach described by Adams in Ch.4,
The Zone System (50 pages of juicy reading) in
The Negative. Adams is at pains to explain the process carefully, but it can still come across as a bit confounding, and that's where practice, practice, comes in. Study it in a quiet place free from distractions (no dogs, kids, wife, computers, etc.!!
Now, I am expecting a few raised eyebrows with this little revelation: I actually dabble in a compacted Zone System with a brute-force Canon EOS 1N (set to fine spot meter), Fuji Velvia 100F and my 'magic wand': a Sekonic L758 1 deg. spot/incident. And what has
that achieved? In addition to some perplexing errors, there have been numerous very revealing tid-bits about how the camera's meter (spot, fine spot mostly or CWA, but
NOT evaluative) observes the scene as opposed to employing the Sekonic and a smaller-range Zone System. Incident readings in difficult light are most educational. With trannnies, the ZS is definitely narrower (necessarily so; tranny film doesn't have the generous latitude of B&W print film). I will point out that it is a bold leap for analogous photographers to stridently ignore the camera (it still is for me) and go by the Sekonic! I am not afraid to assert authority over a well-credentialled camera!
Most of my experiments to this time have taken place in diffuse light with some doubtful scenes (bright hazy to bright point light with highlights and shadows and spectral highs necessitating a "pull-the-scene-apart-bit-by-bit" approach with the Sekonic. As Adams himself points out, point light (i.e. bright sunny day, no clouds) brings up more complications and that is where individual development of negatives, as in LF, can helpto a point.
The Negative is a beaut book (I bought it from Amazon.com, ex USA saving $29.00 of RRP in Australia!!). I read chapter and verse over and over and there are tags on pages, additional scribbled notes, warnings, etc., etc. It joins me on camping and field trips, sitting on the front seat where I can refer to a section quickly.