Cinematography-Theory-And-Practice

ABCDEFFigure 10.20. Exposure on film. (A) is normal exposure — good contrast, a full range of tones, and minimal grain.(B) is the negative of the normal exposure. Notice that it also has a full range of tones from near total black (whichwill print as white) to almost clear negative (which will print as black). (C) is a severely underexposed frame — threestops under. It's dark but also very grainy and doesn't have a full range of tones, hardly anything above middle grays.(D) is the negative of the badly underexposed shot; it's what we call a "thin" negative. (E) is three stops overexposedand (F) is the negative of this shot, it's what is called a "thick" negative, difficult to get a good print from.“Correct” Exposure“Correct” exposure, then, is essentially the aperture setting that willbest suit the scene brightness range of the scene (the horizontal axis: log E)to the characteristic curve of the imaging medium. What is neededis to slip the scene values comfortably in between the toe and theshoulder. A typical scene with a seven stop range of light values fitsnicely on the curve if we place the exposure exactly in the middle. Itis important to remember, however, that correct exposure is a purelytechnical thing; there are occasions where you will want to deviatefrom ideal exposure for pictorial or technical reasons. The relation-exposure197