Lighting designers know how to make the best use of the subtle and powerful medium of light, creating effects that can be changed at will to match the mood of the action.

At its most basic, stage lighting functions to make the actors and their environs visible to the audience. But it can also be used to:

• Evoke the appropriate mood

• Indicate time of day and location

• Shift emphasis from one stage area to another

• Reinforce the style of the production

• Make objects on stage appear flat or three dimensional

• Blend the visual elements on stage into a unified whole

The Designer's work
The lighting designer begins by reading the script to be produced noting the type of light it calls for in each scene. Designer and director share their ideas about how light could be used to enhance the production concept at their first meeting. Early meetings with the set designer are also important because the set and lighting designers must collaborate on how to achieve the desired "look" for the play. The plan for the set may influence the placement and direction of the necessary lighting instruments, so flagging any potential problems in this area as early as possible makes sense.

Lighting designers attend rehearsals to get a feel for the lighting cues and to plan how to light the actors as they move from place to place on stage. When the blocking is set, the lighting designer can start to work out which lighting instruments will be used and where each one will be located.

Planning tools
The planning tools lighting designers use include:

• Paintings and photos showing the mood and style of specific lighting techniques and are gathered through research

• A lighting plot: a scale drawing of the stage and set as seen from above showing the planned layout of each lighting fixture to be used

• A vertical section plot: a cross-section of the stage and set drawn to scale showing the vertical sightlines and the height and position of each instrument

• An instrument schedule: a chart that lists each lighting instrument separately along with the details of its type, wattage, purpose, filter color, the dimmer it will be plugged into and the ciruit that will control it

• A cue sheet: a complete list of the various lighting effects the designer has planned for the show and when they occur

Light control
Lighting designers usually combine both direct and indirect light to illuminate the actors and objects on stage. Direct lighting comes from a definite location and illuminates specific areas; indirect lighting washes over the entire area to be lit and doesn't appear to come from any one specific location.

The amount of light needed to clearly illuminate an object on stage depends on the object's:

• Reflective properties

• Color

• Contrast with its surroundings

• Size

• Distance from the person looking at it.

There are four properties lighting designers can control to create a vast array of effects:

• Intensity. The brightness of light. Everything in the range from the faintest dim glow to the most blinding glare can be created with stage lighting. Contrast has a great impact on how bright a light will appear to be to the audience, with a single flashlight on an otherwise dark stage appearing to be bright, while a strong spotlight shining on an already brightly lit stage may appear dim.

• Color. The color an object on stage appears to be is determined both by its actual hue and by the colour of the light that illuminates it. Filters or gels on lighting instruments make it possible for designers to tint stage lighting in colors that flatter the actors' faces, cast a warm glow over an entire set or heighten the colors of scenery and costumes.

• Distribution. Light can be distributed in different ways on stage. The form of light may vary from a soft unfocused glow to a sharply defined beam that casts dramatic shadows. The beam of light from an instrument may be directed through a piece of metal called a gobo that shapes it into a pattern such as the broken effect of light coming through the leaves of tress. Light may also be directed at an object from any angle, giving rise to an infinite variety of light and shadow combinations, each with a different look and feel.

• Movement. The intensity, color and distribution of light can be noticeably altered as quickly or slowly as the lighting designer and director deem fit while the play is being performed. For example, a scene that starts in the diffuse and rosy light of dawn can end in the brilliant golden beams of full morning light. This capacity for change over time is called the movement of light. It offers a kind of flexible expressiveness that is unmatched by any of the other visual elements of production.

Collaboration
The lighting designer will meet with the director and the design team (set, costume, lighting and sound designers), to discuss the details of the set and the director's interpretation of the play. The set, costume and lighting designers also meet and work together to ensure the creation of a unified look and feel for the production. A lively exchange of initial ideas and first impressions helps clarify the steps that each person needs to take in this intensely collaborative process.

Once the show opens, the designer's work is essentially complete. Now it's normally the job of the stage manager and light crew to make sure that every aspect of the production runs just as the designer intended, time after time, until the production closes.

[Members of AACT can read more on this subject in our Knowledge Base collection of articles.]