a. It is worth noting that the background light is positioned on the same
side of the subject as the key light.
This is because the lighting should
appear to be coming from the same direction, as if the scene were being
illuminated by the sun. You will remember that in three-point lighting, the
key light is the primary light source; therefore, in order to maintain
directional continuity in our lighting, it stands to reason that any background
lighting should come from the same direction as the key light.
b. Figure 3-5 also shows an alternative to using three lights to
accomplish three-point lighting. If, because of electrical power restrictions
or lack of enough lighting instruments, you cannot use three instruments, a
reflector can be used in place of the fill light. The reflector will bounce
enough light back on our subject to adequately fill in the shadow areas cast by
the key light.
Three-point lighting in the field
5. There are many times when three- or four-point lighting is just not
practical to use.
A two-person interview is certainly one of those times.
When lighting for this type of production, whether in the studio or on remote,
it just is not practical to set up three-point lighting for each subject.
Lighting this scene, using the three-point lighting setup would take six
lighting instruments and a great deal of electrical power.
Even if the
lighting instruments and the electrical power are available, the intensity of
the light from so many instruments would be extremely high causing "hot spots"
on your subject.