CHAPTER 5 HOW DIGITAL EXPOSURE SIFTS, MEASURES, AND SLICES LIGHT 77
How Photographers Get in the Zone
How does even an experienced photographer know how much exposure
compensation to use? Next to seat-of-the-pants guesses, the most popular
method is the Zone System. It divides the grayscalerange into 11 zones
from 100% white to 100% black. Each of the zones corresponds to a one-
stop difference from the zones preceding and following it. The Zone System
was developed by Ansel Adams as a way, combined with careful, custom
developing and printing, to give his landscapes the full range of tones possi-
ble in black and white. Is it possible for Adams’s technique to be relevant for
photographers working in color, with no film developing, and in entirely dif-
ferent ways of printing? The answer is yes.Of course, it takes an experienced eye to gauge zones correctly in
the real world, where things are in colors rather than shades of gray.
It’s not necessary, however, to assign a zone value to every color in
a scene. What works is to correctly identify one color that translates
into a Zone V or 18% gray, the middle gray that a digital camera’s
exposure system sees as the proper shade for all things. Take a spot
reading of that color to set exposure, and the entire scene is exposed
correctly. Grass will usually translate as a Zone V; Caucasian skin is
usually a VI; and a shadow from sunlight is often a IV.