really light in zone 6. (Still fromReverie. ©2009 Vincent Laforet. Used with permission.)
By keeping the dynamic range within six stops and exposing the brightest part of the face at 6, Laforet is able to shape the rest of the scene around the blacks, letting the exposure of the man's body fall down to 0; blacks dominate the scene (stressing the nighttime feel of the shot). He allows the Caucasian skin tone to shine the brightest with the face and feet, with part of the arm and hand to hit zone 5, with shadows falling off into the blacks.
Tip: Zone Scale in Practice A typical Caucasian face has a reflectivity of 36%; a brown face, about 16%; a black face, 10%. Green leaves have a 14% reflectance, while black velvet is at 2%. Light grays reflect 70% of light, while off-whites reflect 80% (see Viera, D., & Viera, M. (2005). Lighting for Film and Digital Cinematography, (p.54). Wadsworth). If you want to expose for zone 5 (the “correct” exposure for an 18% mid-range gray card), set your lights and/or place your subject, angle the 18% gray card so that it reflects the same light as your subject, and take your reading. The 18% gray card refers to the reflection and absorption of light (18% of the light is reflected, while 82% is absorbed). If you get an exposure reading of f/5.6 on your light meter for your particular ISO setting, then that's your f-stop setting, and the rest of the tonal range will fall off or increase depending on the amount of light in other areas of the shot. If you're trying to control the amount of detail in the shadows and/or highlights, you can adjust your lights accordingly. Most independent filmmakers and video journalists will usually just eyeball the exposure so that the image on the LCD screen looks right. But if you're really trying to control the image and know that you want the audience to see details in the background, you could plan for it to be two stops dimmer than your main subject in the foreground (which you've exposed at f/5.6 on zone 6), for example. You would light the background for zone 4, and you would know you're in zone 4 when you get a metered reading of f/2.8 at the same speed (ISO setting). At the same time, if you want your audience to see details in the highlights, you could keep the exposure of your highlights in zone 7 (one stop above your main subject of 6, setting your lights and scrims so your meter would not go above f/8).
Tip: Lighting and the Zone Scale A fast way to set your lights so as to brighten or dim your subject is to remember the inverse square law as a main property of light. Doubling the distance of the light from your subject (by either moving the light or your subject) drops off the brightness four times. If you halve the distance, the brightness