The placement of lighting units determines the angle of illumination and the angle at which shadows fall. Pictured are five standard angles along the same horizontal plane: (a) frontal, (b) ¾ front, (c) side, (d) ¾ back, and (e) back. ( Go to the Voice & Vision companion website to see this figure in high resolution.)A specular surface, like a mirror or a polished reflector (a) maintains the directionality of the light rays it reflects. A diffused surface (b), like foam core or a matte reflector, scatters the light rays, changing the quality of the light from hard to soft.The inverse square law. Doubling the distance from the light source to our subject means that the illumination is spread over four times the area and is therefore only one fourth the intensity.Hard light creates sharp shadows (left) because the light beams maintain their parallel direction. Soft light (right) creates diffused shadows because the scattered light beams reach the subject from many directions.Hard light can be softened (diffused) by applying diffusion material in front of it (left) or by bouncing it off a white surface, like foam core (right).This chart shows the color temperatures of various common light sources measured in degrees Kelvin. See the color insert.The placement of lighting units determines the angle of illumination and the angle at which shadows fall. Pictured are five standard angles along the same horizontal plane: (a) frontal, (b) ¾ front, (c) side, (d) ¾ back, and (e) back. ( Go to the Voice & Vision companion website to see this figure in high resolution.)The vertical angle of a lighting unit can dramatically change the look of a subject. Pictured are a high-angle frontal (top) and a low-angle frontal (bottom).The individual elements used in the lighting setup for this scene (a) include the key light (b), fill light (c), backlight (d), and a set light focused on the shelves (e). There are two other lights as well: a small special light on the books and a lamp practical (e). Notice that the lamp is not powerful enough to serve as a backlight, but it provides the motivation for it (d). ( Go to the companion website to see this figure in high resolution and color.)Lighting ratios are expressed as key + fill : fill. To determine this ratio you first measure the intensity of both the key and fill lights falling on your subject (right meter). Then you measure the intensity of only the fill light (left meter) by turning off or shielding your meter from the key light.A cloudy day can present a difficult exposure challenge, because available light can change from second to second, and the difference between sunny and cloudy areas can be as much as 4 or 5 f-stops!Dusk-for-night shooting. Both images were shot at dusk, when some daylight remained but headlights and streetlights had turned on. The left frame was shot with the correct exposure, and the right image was taken 2 stops underexposed, giving the impression of night.Gels come in hundreds of colors and intensities, including color correcting, neutral density, and diffusion media. See the color insert.CTO and CTB gels are used to correct the color temperature of a light source. CTBs are placed on movie lights to make them “daylight” (a), and CTOs are placed on windows to make them “tungsten” (b). See the color insert.With your white balance set for daylight (5,600 K) the sunlight coming through the window will be correct, but the tungsten light (3,200 K) will appear excessively orange (top). Placing a CTB gel over the tungsten unit changes it to daylight (center), matching the color temperature of all sources (bottom). See the color insert.Neutral density gels work like their glass filter counterparts, cutting the intensity of light without changing its quality or color. Pictured are ND 0.6 (left) and ND 0.3 (right).Neutral density gels help control the extreme dynamic range caused by shooting against windows. This subject was shot in a relatively dark interior location with sunny streets visible through the window behind her. Taping ND9 gel on the window brings exterior and interior exposures closer (left half); the right half of the window was intentionally left uncovered.Matte boxes sit in front of a camera lens and block unwanted light from hitting the lens. They can also have filter holders for rectangular glass or plastic filters. This matte box accommodates three filters.Neutral density filters cut the amount of light entering the lens without changing its color. ND 0.3 (left) reduces light by 1 stop and ND 0.6 (right) cuts the light by 2 stops. These are 3 x 3 filters that fit into a matte box filter holder.Diffusion filters are used to soften the image while maintaining sharp focus. Notice in this shot, from Sluser’s Path Lights, the glow on the metal highlights and hair and the softness added to Bobby’s (John Hawkes) face. See the color insert.When shooting shiny or transparent surfaces, the reflected and direct light travel together toward the lens (a). To “catch” reflected light, the pola is rotated until it blocks the off-axis light rays, so that only direct light (b) passes through.The pola filter at work. Glare on the window makes it difficult to see through it (left). Turning the polarizing filter shows the gradual reduction of the light glancing off the window’s surface (center). At its most effective angle, the pola can almost completely eliminate glare (right).Grad filters gradually introduce a filter effect into a portion of the frame. Shown are (from left to right) ND 0.9 grad., ND 0.6 grad., and ND 0.3 grad.Fresnels have a lens (3) that focuses the beam more effectively than open-faced lights. In the spot position (a), the bulb (2) and the reflector (1) are farther from the lens, creating a sharp beam. When flooded (b), the bulb and reflector are brought closer to the lens, creating a wider throw.“Chinese lantern” globes provide a source of soft light, especially for close-ups on faces.Many LED lights designed for film production can be controlled via Bluetooth with a smartphone app like Sidus Link, allowing filmmakers to adjust a light’s color temperature, saturation, intensity, and a variety of lighting effects that can simulate anything from fireworks to a police car’s lights. See the color insert.
