We begin today's discussion with a verse from St. Ansel:

"The incident meter does not, however, give any indication of the difference between a light subject and a dark on, since these qualities can be evaluated only by measuring the light actually reflected from the subject, rather than the light falling on it". Page 166, Chapter 11, "The Camera" .

"Go forth with thine one-degree spot meter, splendidly calibrated, and thou shalt record the truest of exposures". (Satirical paraphrasing)

Now, back to reality. Its well-known that the BTZS methods have debunked one of St. Ansel's Canons. However, I'm perplexed on how this is done. How are the incident readings taken to come up with the bright and dark readings? Can I point my old Gossen Pilot at the dark and bright areas and come up with a Subject Brightness Range (SBR)? Needing some enlightenment here.