THREE-POINT LIGHTING
How to combine a camera light, modeling light
and back light for easy indoor filming
CHARLES H. COLES, ACL
from the Movie Makers – The Magazine for 8mm & 16mm Filmers Jan 1950 p.58
THE-, first and most obvious purpose of any lighting unit in interior filming is to throw enough light on the subject to create adequate exposure. This is not, these days, a difficult operation. We find, for example, that only two RFL-2 lamps (the built-in reflector type) placed six feet from the subject create an exposure of f/2.8 with indoor color film. Two regular No. 2 flood bulbs in efficient metal reflectors at the same distance return
an exposure of f/3.5.
EFFECTS ARE IMPORTANT
However, obtaining adequate illumination of one’s subject should not be regarded as the only purpose of an interior lighting setup. There is the equally important matter of the effect created by one’s light placements. Using only a single lamp for clarity, we examined in December (see How to Place Lights) some of the basic effects at the cameraman’s command—front lighting, three-quarter lighting, top lighting, etc. It will be the purpose of this discussion to show how these effects may be combined through the use of two or more lighting units on a single scene.
CAMERA LIGHT FOR EXPOSURE
To begin at the beginning, let’s double back briefly to single-unit, full front lighting (see Fig. 1). The simplest setup here is to place your lamp in a reflector and to position it close to the camera and preferably slightly above it. This is lighting for exposure only. For, such shadows as are cast by this light placement will fall behind the subject, are unseen by the camera and therefore create no sense of depth and modeling. Adding more units in the same front position will, of course, raise the exposure level—but it will in no way change the lighting.
MODELING LIGHT FOR DEPTH
Thus, adequate as full front lighting may be for exposure, it soon becomes uninteresting. It creates no effect. A second light source is needed off to one side to create an illusion of depth. This second, or modeling, light is placed several feet to the right or left of the subject and is raised high so that it may be directed downward at an angle of about 45 degrees. We have now illuminated the subject with what is commonly called portrait lighting.
In Fig. 2, for example, the modeling light is coming in high and from the right. Its effects are the following: ( 1 ) it highlights pleasingly the left side of the girl’s face and hair; (2) in so doing, it casts shadows on the right side of the face, and (3) it helps to illuminate for exposure the little girl’s doll. The front (or camera) light source, in the meantime, still carries on its primary function
of illumination for exposure—and also serves to lighten the shadows purposely cast on the face. (The relative positions of these two units, by the way, are graphically revealed in the two tiny hotspots on the telephone mouthpiece.)
TWO UNITS SHOULD MATCH
Here, then, is a basic and quite effective two-light setup. As illustrated, it actually has employed only two No. 2 photofloods in metal reflectors. But there is no reason why it should not employ, in the same arrangement, twice or three times as many lamps if they are needed for exposure. There is, however, one thing to remember. For the best balanced results, the lamps used at one position (camera light) and the lamps used at the other (modeling light) should be of equal number and strength. It is in their unequal distances from the subject that one group out-illuminates the other.
LIGHT ON BACKGROUND
So far so good. But let us see now if we can improve our effects still further. We note, for example, that the background in Fig. 2 is dark and unnatural in comparison to the warmly lighted figure. A third light source is needed to raise the entire exposure level and in so doing bring the background into better balance (see Fig. 3).
We will not want this setting to be of equal strength with the subject, but rather at a contrast range of around 1:2 or 1:3. Exposure meter readings on subject and setting soon will determine the correct level.
BACK LIGHT FOR BRILLIANCE
If still another light source is available, it may be used profitably to provide back lighting on the subject (see Fig. 4). This back light is an effect light only, contributing nothing to the overall exposure. It does contribute to the picture, however, in three important ways: (1) it outlines the subject, pulling it away from the background and heightening the sense of depth; (2) it rounds out the lighting on the hair, and (3) it adds sparkle and brilliance to the entire picture. Positioning your back light behind the subject requires some ingenuity. First off, neither it nor its support may be seen by the camera. One method is to use an RSP-2 lamp (or the less powerful 375 watt medium beam) in a clamp-on holder. This in turn is clamped to the picture molding near the ceiling or to a handy Venetian blind, an open door or a high bookshelf. A light boom, of course, is the ideal support for your back light, since it is readily maneuverable and specifically designed to position lamps high and out of camera range. Although not yet widely used by amateurs, these booms will gain increasing favor as their handiness is appreciated. (For data on commercial light booms, see Equipment Survey: 8, December, 1949; for a homemade unit, see Build Your Own Boom, January, 1950.)
PROTECT FROM FLARE
Secondly, not only must your back light be unseen by the camera, it also must be placed so that it cannot throw light directly on the camera lens. Ordinary flood lamps of either type—and even the built-in spot lamps—tend to spill enough light onto the lens to cause flare, especially if the lens glass is uncoated. They should, therefore, be mounted in a deep and narrow reflector (see Fig. 5), and the lens should be further protected by an efficient lens hood. Still safer (and more effective in back lighting) is the use of the Fresnel-type spotlight. Highly controllable, such a unit puts the light beam exactly where you want it—and nowhere else.
Finally, if you are short on lighting units, or if you have only a single 15 ampere circuit (on which it is unsafe to burn four No. 2 lamps), a very pleasant lighting effect can be maintained by foregoing the modeling light. The other three units are kept as outlined— with the effect as seen in Fig. 6. There are other ways to use lights, of course. But the arrangements described here are basic light positions for most movie making. They’re simple to set up, and you’ll notice that they work equally well for color or black and white.