Auditorium Lighting Systems

Types of Lighting in the Auditorium
A typical modern auditorium is equipped with many lighting systems.

House lighting is incandescent lighting, usually at low levels, frequently decorative, controlled on dimmers, and is intended to show the room to its best advantage. House lighting can be expensive to run and maintain. To save money the use of house lighting is strictly limited to times when the audience is present. To achieve the best results we limit house lighting to the seats and do not light the walls at all. Or we strictly limit the downlights to the seats and light other surfaces with a separate set of very dim lights optimized for those surfaces.

This means locating no downlights near the walls. In a 30' high portion of the auditorium there would be no downlights within 15' of the walls. We find it is best to light the side seats 1/4 as bright as the center seats, and best to light the rear seats 1/10 as bright as the center seats.

It is essential that the house lighting does not light the stage or orchestra pit at all. Lighting the stage and pit is exclusively the province of the stage lighting system and therefore the house lighting system must stay away completely. With the houselights on and the stage lights off, the stage and orchestra pit should look completely black.

Work lighting is a bright, cheap, and efficient system intended for cleaning and maintaining the room. Technical areas such as catwalks require separately switched white and blue work lighting.

Aisle lighting is usually mounted on chairs, and can be concealed under the armrests if desired. The old standard design - every third row on alternating sides of the aisle - now looks too dim and uneven, and is inadequate. The current audience expectation is to have lights at every row on both sides of the aisle. Where the aisle has steps the aisle lights must be raised well above tread level. This means the seating manufacturer may need to supply two or more types of chair "aisle standards" with the aisle lights located at different elevations to suit different heights of adjacent treads; a high location for the stepped aisles in the balcony and a low location for the ramped aisles in the orchestra, for example.

Egress lighting is the required lighting on egress passageways that must be kept on, by law, at all times the room is occupied. Egress lighting includes aisle lights, lighting on crossaisles, lighting in vestibules, and lighting on all other legal means of egress. The owner wishes to run these lights only when the auditorium is occupied, not 24 hours a day: so the aisle and egress lighting needs to be switched from a convenient location. The switch should be posted with a sign saying "Egress lights shall be kept on when the room is occupied." Aisle and egress lights are used during the performance. Providing too much light is as big a problem as providing too little. Aisle and egress lights must be silent and discreet. Only incandescent lighting is silent and discreet. Fluorescent and compact fluorescent sources are neither silent nor discreet, and are not suitable.

Exit lighting is the red or green exit signs above egress doors. Exit signs near the stage are very objectionable. The only good solution is to not locate exit doors anywhere near the stage.

Emergency lighting is lighting that is normally off, and that turns on automatically when utility power fails, even if it's the middle of the night. We find that the many available schemes to transfer house lighting electrical circuits from their normal supply of electricity to an emergency supply are all too complicated, too costly, and have too many adverse side effects. We prefer instead to install a dedicated set of normally-off emergency-only lights. While this may seem at first to be inefficient, when the full complexity of legally transferring circuits between normal and emergency supplies is known, then dedicated emergency lights seem very efficient by comparison.

Emergency lights are normally energized by an emergency generator. Where there is no emergency generator an inverter can be used. Where there is no inverter, remote-head battery packs can be used. Do not locate battery packs in the stage or auditorium; the battery chargers are too noisy and need to be located remotely.

Stage Lighting
About a quarter of all stage lighting is located in the auditorium. Usually we look for 8 lighting positions: near box booms left and right, far box booms left and right, near catwalk over the apron, mid catwalk with the lenses about 45 degrees to the actors nose, far catwalk at the ideal followspot angle, and a low-angle position for projection and effects.

The ideal followspot angle changes depending on the precise needs of the project, and is about 30 degrees. Steeper followspots are used for dance, for shallow stages, and for directors and designers who object to the followspot beam falling on the upstage scenery. Lower followspot angles are used for television, for especially low proscenium arches, for very deep stages, to shoot under "found" obstructions, and in renovations where "found" followspot positions are re-used. The quantity of stage lighting positions needed in the auditorium varies with the size of the venue.

Really big venues - 20,000 seats - need fewer lighting positions, and small venues - 70 seats - need more lighting positions. We found this through experience and assume it's because the nearer the audience is, the more the slight differences between lighting angles actually matter. A common flaw of modern theaters is to locate the stage lights in the auditorium too far away from the actors. The closer the lights are to the stage (within limits of course) the better the lighting will be. Even with newer spotlight designs this rule still applies.

Another common flaw is to let the lighting infrastructure peter out downstage. In older theaters the greatest density of stage lighting was concentrated "in one", or immediately behind the house curtain, because very little stage space and very little action happened downstage of the curtain. The situation is very different today. Now typically there is much more stage space and much more action downstage of the curtain. As any performer moves downstage the lighting should keep getting brighter and better without limit. It is an obvious mistake when a performer takes a few last steps toward the audience and gets darker instead of brighter. The apron lighting should be brighter and better than the "in-one" lighting behind.

Rehearsal lighting is provided in the auditorium so the director can see the actors rehearse in a flattering and revealing light.

Ghost lights are left on all night to help people avoid falling or tripping on the many hazards in the auditorium, such as the orchestra pit. Because ghost lights are left on all night they are chosen to be extremely low wattage, extremely efficient, and extremely long life. The name "ghost light" is a long-standing theater tradition. Outside the theater these would be called night lights or security lights.

Classroom Lighting
When a theater or concert hall does double duty as a classroom, then it also needs to be lit as a classroom. Classroom lighting requirements can vary from well-shielded very dim lighting for taking notes during audio-visual presentations to the 80 footcandles or more required for giving examinations. Good designs hide the classroom lights - sometimes by using indirect lighting - because the fixtures capable of producing 80 footcandles efficiently always look inappropriate, that is to say "ugly", in a performing arts room, even when they're not turned on.

Orchestra pit lighting is usually done with music stand lights. It is usually desirable for the pit to have no other lighting. For orchestra pit work lights we prefer stand-mounted cord and plug portable fixtures because of the great danger of accidentally turning on the permanent pit worklights at the wrong time.

Some theaters need conductor "specials" to light the conductor. Conductor "specials" may light the conductor continuously during performances so the performers can see the conductor well or may make the conductor more visible on the conductor monitor video camera. Some theaters have conductor "specials" for "conductor bows" and curtain calls because the normal followspots cannot hit the conductor or because an extra stagehand would be needed to run a dedicated conductor followspot.

Orchestra pits rarely have enough power for all the stuff that goes in them. If there is a labyrinth of corridors leading to and from the pit we add aisle lights in the corridors to guide the way.

Cue lights inform the conductor and stage hands in the auditorium when to "take" their cues. Cue lights can be simple on/off low-wattage bulbs, or can be sophisticated color-coded answer-back systems.

Infrared illuminators are sometimes required for the infrared night-vision video monitor cameras. These allow the stage manager and other staff to see the stage during complete blackouts.

Dance spotting lights are small red bulbs located in precise positions low in the back of the auditorium or on the balcony rail. They are used by dancers for alignment and for keeping their orientation during spins and turns. Each dance company has their own preferences for the quantity, location, and type of spotting lights.

Curtain warmers light the curtain and make it come alive. Curtain warmers can be simple flat washes or can be multicolored textured light designed to enhance some aspect of the curtain or to be part of the image and style of a particular production. Curtain warmers might, for example, be different in the winter than in the summer, or might be different for formal evenings than for informal evenings, or might be different for each production. We have designed curtain warmer installations up to 32,000 watts, though they are usually much smaller.

Broadcast Television Lighting
Some venues have permanent provisions for lighting the stage and audience for broadcast television. Audience lighting provides adequate coverage for "establishing shots" and for tight shots on the audience's faces. Some venues rely on the TV production company to provide the broadcast lighting equipment for stage and audience lighting, in which case the house provides only the appropriate power and fixture locations.

Apron Lighting
A large stage apron needs a full compliment of stage lighting. When used for miscellaneous purposes the stage apron may also need orchestra rehearsal and performance lighting and lighting for meetings, A/V presentations, lectures, and so on.

Blue Lights
Stage worklighting can include a complete set of white worklights and a second set of dim running lights, called the "blue light" system. These two systems are installed in all technical locations in the auditorium and stage, including catwalks, gridiron, galleries, trap room, crossover, followspot room, control rooms, corridors, stairs, and so on.

Blue lights are not necessarily blue, but are dim and are concealed from the audience. Blue lights permit staff to work safely, conveniently, and invisibly during the performance. Permanent blue lights reduce the need for portable worklights, but are usually supplemented with portable blue light fixtures for specific production needs, such as for escape stairs and backings.

In a typical modern installation blue lights are controlled simultaneously by three control systems: 1) work light switches, 2) house light switches, and 3) the stage lighting control console. This permits local control by local switches, central control by houselight preset pushbuttons, and control during performances by the stage lighting control console. Any cue on the stage lighting console can include changes in the white and blue worklights.