What is fully controlled lighting?
If you are working in the studio, or some other area where you have complete control, try to build up your subject lighting one source at a time – each unit should have a role to play. It is useful to keep the camera on a tripod so you can keep returning to it to check results from this viewpoint every time you alter the light.
Starting from darkness, switch on your main light (soft or hard) and seek out its best position. If you are just showing a single textured surface – such as a fabric sample, or weathered boarding – try a hard light source from an oblique direction. By ‘skimming’ the surface it will emphasize all the texture and undulations. But take care if this means that one end receives much more light than the other – move your light source farther away.
A single hard light will probably exaggerate dips in the surface into featureless cavities. Also, if the picture includes other surface planes at different angles, some of these may be totally lost or confused in shadows. One solution is to introduce a second or ‘fill’ light, but if this creates a second set of hard shadows the scene will tend to look ‘staged’ and theatrical, because we are rather conditioned by seeing the world lit by one sun, not two. To avoid this try adding very diffused light – perhaps just ‘spill light’ from the first source bounced off a white card reflector – sufficient to reveal detail in what still remain shadows.
The reflector will have to be quite large, and probably set up near the camera to ensure it redirects some light into all shadows seen by the lens. If you cannot produce enough fill-in in this way, try illuminating your reflector card with a separate lighting unit. Another approach is to change your harsh main light to something of softer quality, perhaps by diffusing it.
If your picture contains a more distant background, you can light this independently with
a third source (maybe limited by barn doors) so that the surface separates out from the main subject in front. Again, be careful not to spread direct light into other areas, if this creates confusing criss-cross shadows. In fact, when you have a great mixture of objects and separate planes to deal with in the same picture, there is a lot to be said for using one large, soft, directional light source (i.e. from one side and/or above). This can produce modelling without excessive contrast or complicated cast shadow lines, giving a natural effect like overcast daylight from a large window or doorway.
Much the same kind of build-up can be applied to formal studio portraiture. Decide viewpoint and pose, then pick the direction of your main light, watching particularly for its effect on nose shadow and eyes. With a ‘three-quarter’ head shot think carefully whether the larger or the smaller area of face should be the lighter part. Consider how much, if any, detail needs restoring in shadows by means of a reflector. If you want to stress an interesting outline you could light the background unevenly, so that darker parts of the sitter appear against the lightest area of background, and vice versa. It is often a good idea to light backgrounds completely independently as it allows you much greater control.
You could even add a farther low-powered or distant spot to rim-light hair, shoulders or hands from high at the rear. However, there is a danger of so-called overlighting which puts your sitter in a straitjacket. He or she cannot be allowed to move more than a few inches for fear of destroying your over-organised set-up, and this can result in wooden, self-conscious portraits. The more generalised and simple your lighting, too, the more freely you can concentrate on expressions and poses.