The Theory of Light

Most of what we know about lighting comes from a single period of art history.

In the early 1600s, a painter named Caravaggio developed a style of painting that used shadows to express depth on a two-dimensional canvas. An admirer of his went on to perfect this style and become one of the most famous painters in history: Rembrandt van Rijn (1606_ 1669). This painter, commonly known simply as Rembrandt, created a way of working with light and shadow that transcended his own time and medium and survived well into modern times. The technique is called chiaroscuro, an Italian word meaning "light-dark." Rembrandt's paintings have very clear—but not necessarily visible—sources of light that only illuminate selected parts of the frame. Even his outdoor scenes made use of clouds and their shadows to provide areas of light and dark within the picture. Rembrandt's style depicted light sources as being natural. Light in his paintings—as in life—could only come from a naturally occurring source. No one has ever found a better way of lighting since. There are three main characteristics of chiaroscuro lighting, as discussed next.

The Source and Intensity of Light There is only one apparent light source that selectively lights only parts of the scene. The overall illumination is low—called low-key lighting—and the overallLightingTriangleThis is the basic lighting triangle formula that will give a chiaroscuro look. This idea can be applied to almost any situation. background is darker than the subject of the shot.

Shadow Direction and Fall-off Dense, attached shadows make the direction of the light readily apparent. The quick fall-off, or diminishing of the light's intensity before reaching the background, allows darker areas of the frame to dominate, thus directing the viewer's eye to the lighter areas, that is, the subject.

Object Texture This highly directional light source accentuates the texture and form of objects in the frame. Faces, clothing, furniture, walls, and even dust in the air take on a three-dimensional quality. 

Chiaroscuro lighting can convey both high and low emotional intensity. The quantity of dark and light areas helps determine what the perception will be. This type of lighting uses a low-key technique, usually a Fresnel spot with barndoors, and very little fill. The background is usually lit with other very directional, narrow-beam lights to control the amount of the scene receiving light.

Chiaroscuro lighting intensifies the three-dimensional properties of the subjects, clarifies the space around them, and gives an emotional quality to the scene. The particular emotional quality should be selected based on the subject you are photographing in ENG work and on what the script calls for in EFP. Each lighting setup should have a predetermined goal beyond making a good exposure for the camera. Chiaroscuro lighting is the basis for almost all the motivational lighting you will do. (See example right)

The Rembrandt Way
Chiaroscuro lighting is now more popularly known as Rembrandt lighting. Try these five points as a guideline to Rembrandt lighting:
 • Place the key light, or angle the subject, so the shadowed side of the subject is closest to the camera (so it appears the subject is looking into the direction of the light but not at it).
• Move the subject away from the background.
• Look for a dark background.
• Make the subject the brightest and/or biggest area of the shot.
• Have the darkest area of the background directly behind the subject.

The Rembrandt style can work for everything—not just for setting up lights but in simply positioning subjects in any shot. Our plane-crash witness mentioned earlier can have a chiaroscuro feel by positioning his head in the shot against the dark foliage of a tree and having him face in the direction of the flashing fire truck lights. The red lights become the subliminal key light source giving texture to his face, even though they do not overpower the diffused daylight. The dark tree makes his face the brightest area of the picture. This is simple and quick, yet it meets the artistic standards of Rembrandt on a very basic level. (See example below.)

LightingRembrandt(A) A simple example of Rembrandt lighting: dark shadows and background, with a single motivating light source opposing the direction of the subject. (B) The lighting setup used to create the Rembrandt scene

Zone Lighting
Along the same lines as chiaroscuro lighting, zone lighting selectively lights only certain areas of the picture, which are divided into zones by distance from the camera. This is usually the foreground, midground, and background. The subject is usually in the midground. Each of these areas is lit separately, with dark or shadow areas separating them. This technique helps to create a three-dimensional look and to draw the eye to whatever you wish to emphasize in the frame.