Digital BW, The Print

I think that you have your zones reversed. In photosensitometry (and 
Adams' application of it), zone 1 represents mostly film base fog 
(nearly no exposure) thus, deepest shadow, or in your "12 bit" example, 
1 level of gray.

Thanks for sharing your analysis. It's what I have read, too other than 
the above.

Hal Gage