Light Source: Controlling Light

The other day, I presented some footage to my class to see if it could identify the lighting techniques used during the production. At one point, an on-screen character moved a lamp and the small circular glow above the lamp and the light shining on the wall faded as the lamp moved away. While looking perfectly natural to the eye, the resulting light changes were the result of careful planning and coordination between the actor, a lighting grip holding a flag and the person in charge of lighting the set. What actually happened was quite simple and incorporated the use of two basic lighting designer tools the flag and a snoot. The light designer created the effect by hanging a small lighting instrument with a snoot attached, above the scene.

The lamp actually contained a small 15-watt bulb so that the fixture would not glow too brightly in the scene. A supplemental, soft-gelled snooted light created a small round glow above the lamp. As the actor moved the light away, the lighting grip moved a flag in front of the hanging light. The result was a slow dimming of the light as if it was the lamp moved away. This lighting effect is just one way you can control light. In this column, we will take a look at the various tools you can use to manipulate and control light.

Flags, Barndoors and Snoots

Controlling the lighting on a set often means creating shadows. Keep in mind, when setting up your lighting, that shadows make your scene three-dimensional. Because television and film is a two-dimensional medium, it is up to you to create a three-dimensional world. Three tools that help create this shadowy world are flags, barndoors and snoots.

A flag is typically a square piece of opaque cloth or cardboard, usually black, which is attached to a sturdy, lightweight frame. This tool is usually about three-foot square, but may come in a variety of sizes and shapes. You place the flag in front of a light so that it casts its shadow on the object or set piece you are shooting. You can also use a flag to shade the lens of the camera to prevent lens flare caused by a light shining into the camera lens.

Barndoors are four overlapping metal doors attached to the front of a lighting instrument. As you open or close the doors, you change the size of the light. You also control the spill of the light. When adjusting the barndoors, watch the set or object you are taping. Open the doors so that the light falls precisely where you want. With barndoors, you can adjust the spill of light from the top and bottom as well as the two sides of the light source.

A snoot is a long cylinder that you attach to your lighting instrument. The snoot controls the spill of the light by turning it into a more focused round light source.

Techniques for Controlling Light

I once took some students to a commercial shoot to give them a chance to see professionals work together to accomplish a common goal. The students in the class, especially those who were leaning towards the performance side of the business, were amazed at the tight space in which the actor worked. Although the commercial was shot in a large sound stage, the actor was hemmed in by a variety of C-stands holding reflectors, flags and, of course, lights. As I walked them through the setup, they realized that each of the flags and reflectors had a distinct job.

In front of and slightly above the camera lens, a flag shaded the lens from the back light, preventing lens flare. A small flag placed in front of the key light cast a shadow on a glass that the director lit from behind with a special light. The key light still did its job providing light for the talent, but without the flag, there would have been an unwanted bright spot on the glass. The director placed another flag between the back light and the glass to prevent its light from falling on the glass and another diffused light was used to illuminate the glass and its contents. To highlight the glass and give it a bit more sparkle, he placed a small golden gelled light with a snoot slightly behind and above the glass to add a sparkle to its rim and its contents. The lighting designer kept this golden light off the talent by using the snoot and focusing the light on the glass. As the sparkling champagne rose in the glass, the golden light made each bubble sparkle.

In addition to flags, the light designer further controlled the spill from the key and fill lights by placing them 45 degrees above the talent and using barndoors. The doors were opened so the edge of each door’s shadow was directly above and below the camera’s shot of the talent, but were closed enough to match the edge of the background. The angle of light allowed the shadow of the light to fall below the talent, thus keeping its light off the backdrop.

The background lights created a series of colored diagonal streaks across the mid-gray backdrop. Because the spill from the key and fill light was controlled so it wouldn’t hit the backdrop, the mid-gray drop turned to a dark gray, almost black color. Keeping the light off the backdrop eliminated the problem of washing out the backdrop light colors. The results were a very rich blue and gold streak splashing across the drop, directly behind the talent. The lighting director created the streak by closing the top and bottom barn doors as tight as possible and angling the doors so that they made a diagonal streak across the drop. (See Lighting Backdrops with Color sidebar.)


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Shadows Are the Key

Flags, barndoors and snoots all work to create shadows and prevent light spill. And shadows give dimension to a video picture. Light designers always work with shadows and light and have to know how to manipulate both. By using these three lighting accessories, you can create shadows that will help turn your scenes into three-dimensional images.

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