Combined Lighting for Digital Films
When you no longer are bound to a single light source, you can use a few to create the proper lightscape for your DSLR film, but there’s a vast difference between creating a symphony of illumination and using a bunch of lights. One radiates light in all the right places, whereas the other makes you want to cringe.
Getting in touch with the former and avoiding the latter require a fundamental understanding of using light effectively. That task revolves around controlling the shadows and creating a sense of depth between the subject and the background.
Three-point film lighting
The most common technique for effectively lighting a subject relies on a three-light setup. Working together, the subject is lit from one side, the shadows filled on the other, and a third light provides depth by separating the subject from the background.
Rooted in still photography, this method works just as well with your movie. When you place the lights in a stationary position, you can capture an on-camera interview, descriptive action and b-roll, and even many situations with a live-action film. So this method is a keeper. For moving subjects, you can use a modified light array to produce the same effect.
The film’s main light
A main light is, uh, the main light in the scene. The most well-known main light is the sun. On the pro-active side of the fence, consider a main light to be the main artificial light used to illuminate the subject.
This light works best when it’s positioned near the camera at about a 45º angle from the subject so it broadly covers one side of the subject’s face. The other side renders in shadow, either appearing quite dramatic or as half of a face.
Film with a fill light
The naming convention for the role of this light is spot-on because that aforementioned shadow on the opposite side needs a little exposure to show some detail. Just a little — any more and the fill light no longer lives up to its moniker. Like the main light, you also position it at a 45º angle from the subject, only on the opposite side of the camera from the main light.
Depending on the subject, you can position the fill light at either a higher or lower angle than the subject to effectively fill in the shadow areas. The fill can also be a reflector that redirects illumination from the main light. When you're shooting outdoors, this comes down to being a large white reflector bouncing sunlight back on the subject.
When you're using an artificial light for fill, be sure it doesn’t overpower the main light. You can do this several ways:
Use a bulb with less wattage.
Adjust the dimmer to output less light.
Place a neutral density filter over the light.
Move the light further from the subject.
Film with a backlight
After the front of the subject is adequately covered, put some light behind them to add depth and separate the subject from the background. Position this light high and off to the side behind the subject at a 45º angle. Also called the hair light, a backlight illuminates the subject from the side and provides separation from the background, exaggerating the feeling of depth.
Four-point film lighting
Using a background light, not to be confused with a backlight, illuminates the background and not the subject. This serves several functions, including creating an interesting visual effect and a means for further reducing background shadows.
Even more lights
Sometimes, the more the merrier, but other times, less is more. Here are some of the lights you can use to enhance a scene:
Dedicated hair light: The back part of three-point lighting serves many functions, including as a hair light, but having a light specifically for hair is the real deal. That’s because its only purpose is to highlight the locks. Unlike the generic backlight, which uses a broad swath of light, this light either has the barn doors narrowing the beam, or it uses a snoot.
Accent lighting: Accent lighting is similar to a hair light. Its sole purpose is to bring attention to a detail in the scene. You can use a single accent light or a group to bring attention to details in the scene.
Using background patterns: You can effectively use light as a background element. Shining a beam to create form from the light or using a gobo in front of the light produces an interesting effect. (A gobo is a perforated metal slide that comes in a variety of patterns. Some resemble venetian blinds; others form geometric shapes.)