HOME

TheInfoList



OR:

Stage lighting is the craft of
lighting Lighting or illumination is the deliberate use of light to achieve practical or aesthetic effects. Lighting includes the use of both artificial light sources like lamps and light fixtures, as well as natural illumination by capturing daylig ...
as it applies to the production of
theater Theatre or theater is a collaborative form of performing art that uses live performers, usually actor, actors or actresses, to present the experience of a real or imagined event before a live audience in a specific place, often a stage. The p ...
,
dance Dance is a performing art form consisting of sequences of movement, either improvised or purposefully selected. This movement has aesthetic and often symbolic value. Dance can be categorized and described by its choreography, by its repertoir ...
,
opera Opera is a form of theatre in which music is a fundamental component and dramatic roles are taken by singers. Such a "work" (the literal translation of the Italian word "opera") is typically a collaboration between a composer and a librett ...
, and other
performance A performance is an act of staging or presenting a play, concert, or other form of entertainment. It is also defined as the action or process of carrying out or accomplishing an action, task, or function. Management science In the work place ...
arts.
Stage Lighting Design Principle and Process
Several different types of stage lighting instruments are used in this discipline.
theatrecrafts' Types of Lanterns.
In addition to basic lighting, modern stage lighting can also include special effects, such as Laser lighting display, lasers and fog machines. People who work on stage lighting are commonly referred to as
lighting technician Electrical lighting technicians (ELT), or simply lighting tech, are involved with rigging stage and location sets and controlling artificial, electric lights for art and entertainment venues (theatre or live music venues) or in video, television, o ...
s or
lighting designers In theatre, a lighting designer (or LD) works with the director, choreographer, set designer, costume designer, and sound designer to create the lighting, atmosphere, and time of day for the production in response to the text while keeping i ...
. The equipment used for stage lighting (e.g. cabling, dimmers, lighting instruments, controllers) are also used in other lighting applications, including corporate events,
concerts A concert is a live music performance in front of an audience. The performance may be by a single musician, sometimes then called a recital, or by a musical ensemble, such as an orchestra, choir, or band. Concerts are held in a wide variet ...
, trade shows, broadcast television, film production, photographic studios, and other types of live events. The personnel needed to install, operate, and control the equipment also cross over into these different areas of "stage lighting" applications.


History

The earliest known form of stage lighting was during the early Grecian (and later the Roman) theaters. They would build their theatres facing east to west so that in the afternoon they could perform plays and have the natural sunlight hit the actors, but not those seated in the orchestra. Natural light continued to be utilized when playhouses were built with a large circular opening at the top of the theater. Early Modern English theaters were roofless, allowing natural light to be utilized for lighting the stage. As theaters moved indoors, artificial lighting became a necessity and it was developed as theaters and technology became more advanced. At an unknown date, candlelight was introduced which brought more developments to theatrical lighting across Europe. While
Oliver Cromwell Oliver Cromwell (25 April 15993 September 1658) was an English politician and military officer who is widely regarded as one of the most important statesmen in English history. He came to prominence during the 1639 to 1651 Wars of the Three Ki ...
was ruling Britain, all stage production was suspended in 1642 and no advancements were made to English theaters. During this theatrical famine, great developments were being made in theaters on the European mainland. Charles II, who would later become King Charles II witnessed Italian theatrical methods and brought them back to England when he came to power. New playhouses were built in England and their large sizes called for more elaborate lighting. After the refurbishing of the theaters, it was found that the "main source of light in Restoration theaters to be chandeliers" which were "concentrated toward the front of the house, and especially over the forestage". English theatres during this time used dipped candles to light chandeliers and
sconce Sconce may refer to: *Sconce (fortification), a military fortification *Sconce (light fixture) *Sconcing, imposing a penalty in the form of drink *Sconce Point Fort Victoria is a former military fort on the Isle of Wight, England (), built to ...
s. Dipped candles were made by dipping a wick into hot wax repeatedly to create a cylindrical candle. Candles needed frequent trimming and relighting regardless of what was happening on-stage because "they dripped hot grease on both the audience and actors". Chandeliers also blocked the view of some patrons. There were two different types of Restoration theaters in England: Restoration commercial theaters and Restoration court theaters. Commercial theaters tended to be more "conservative in their lighting, for economic reasons" and therefore used "candle-burning chandeliers" primarily. Court theatres could afford to "use most of the Continental innovations" in their productions. Theaters such as the Drury Lane Theatre and the Covent Garden Theatre were lit by a large central chandelier and had a varying number of smaller stage chandeliers and candle sconces around the walls of the theaters. Two main court theaters, built between 1660 and 1665, were the Cockpit Theatre and the Hall Theatre. Chandeliers and sconces seemed to be the primary lighting sources here but other developments were being made, especially at the Hall. By the 1670s, the Hall Theatre started using footlights, and between 1670 and 1689 they used candles or lamps. It can be noted that by the end of the 17th century, "French and English stages were fairly similar". There is not much written on theatrical lighting in England at the end of the 17th century and from the little information historians do have, not much changed by the middle of the 18th century. Gas lighting hit the English stage in the early 1800s beginning with the Drury Lane and Covent Garden theaters. In the 1820s, a new type of artificial illumination was developed. In this type of illumination, a gas flame is used to heat a cylinder of quicklime (calcium oxide). Upon reaching a certain temperature, the quicklime would begin to incandesce. This illumination could then be directed by reflectors and lenses. It took some time from the development of this new Limelight before it found its way into theatrical use, which started around 1837. Limelight became popular in the 1860s and beyond, until it was displaced by electrical lighting. Lighting advances made in English theaters during this time frame paved the way for the many lighting advances in the modern theatrical world.


Functions of lighting

Stage lighting has multiple functions, including: * Selective visibility: The ability to see what is occurring on stage. Any lighting design will be ineffective if the viewers cannot see the characters, unless this is the explicit intent. * Revelation of form: Altering the perception of shapes onstage, particularly three-dimensional stage elements. * Focus: Directing the audience's attention to an area of the stage or distracting them from another. * Mood: Setting the tone of a scene. Harsh red light has a different effect than soft lavender light. * Location and time of day: Establishing or altering position in time and space. Blues can suggest night time while orange and red can suggest a sunrise or sunset. Use of mechanical filters ("gobos") to project sky scenes, the Moon, etc. * Projection/stage elements: Lighting may be used to project scenery or to act as scenery onstage. * Plot (script): A lighting event may trigger or advance the action onstage and off. * Composition: Lighting may be used to show only the areas of the stage which the designer wants the audience to see, and to "paint a picture". * Effect: In pop and rock concerts or DJ shows or raves, colored lights and lasers may be used as a visual effect. Lighting design is an art form, and thus no one way is the "correct" way. There is a modern movement that states that the lighting design helps to create the environment in which the action takes place while supporting the style of the piece. "Mood" is arguable while the environment is essential.


Qualities in lighting


Intensity

Intensity is measured in lux, lumens and
foot-candle A foot-candle (sometimes foot candle; abbreviated fc, lm/ft2, or sometimes ft-c) is a non- SI unit of illuminance or light intensity. The foot-candle is defined as one lumen per square foot. This unit is commonly used in lighting layouts in par ...
s. The intensity of a luminaire (lighting instrument or fixture) depends on a number of factors including its lamp power, the design of the instrument (and its efficiency), optical obstructions such as color gels or mechanical filters, the distance to the area to be lit and the beam or
field angle Field may refer to: Expanses of open ground * Field (agriculture), an area of land used for agricultural purposes * Airfield, an aerodrome that lacks the infrastructure of an airport * Battlefield * Lawn, an area of mowed grass * Meadow, a grass ...
of the fixture, the color and material to be lit, and the relative contrasts to other regions of illumination.


Color

Color temperature is measured in
kelvin The kelvin, symbol K, is the primary unit of temperature in the International System of Units (SI), used alongside its prefixed forms and the degree Celsius. It is named after the Belfast-born and University of Glasgow-based engineer and phys ...
s. A light's apparent color is determined by its lamp color, the color of any gels in the optical path, its power level, and the color of the material it lights. A tungsten lamp's color is typically controlled by inserting one or more gels (filters) into its optical path. In the simplest case, a single gel is inserted into the optical path to produce light of the same color. For example, a blue gel is used to create blue light. Custom colors are obtained by means of subtractive CMY color mixing, by inserting combinations of cyan, magenta and yellow filters into the optical path of the lighting fixture. The inserted filters may have varying densities, with correspondingly varied percentages of transmission, that ''subtractively'' mix colors (the filters absorb unwanted light colors, but the desired colors pass through unaffected). Manufacturers will sometimes include an additional green or amber ("CTO" color correction) filter to extend the range (gamut) of subtractive color mixing systems. Lamp power also influences color in tungsten lamps. As the lamp power is decreased, the
tungsten Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolat ...
filament in a bulb will tend to produce increasing percentages of orange light, as compared to the nearly white light emitted at full power. This is known as ''
amber shift {{unreferenced, date=December 2009 Amber shift is a phenomenon of Incandescent light, incandescent lamps in which the perceived warmth (or colour temperature) of the light sources changes as larger amounts of electric current flow through it. Bas ...
'' or ''amber drift''. Thus a 1000-watt instrument at 50 percent power will emit a higher percentage of orange light than a 500-watt instrument operating at full power. LED fixtures create color through additive color mixing with red, green, blue, and in some cases amber, LEDs at different intensities. This type of color mixing is often used with borderlights and
cyclorama A cyclorama is a panoramic image on the inside of a cylindrical platform, designed to give viewers standing in the middle of the cylinder a 360° view, and also a building designed to show a panoramic image. The intended effect is to make view ...
lights.


Direction

Direction refers to the shape, quality and evenness of a lamp's output. The pattern of light an instrument makes is largely determined by three factors. The first are the specifics of the
lamp Lamp, Lamps or LAMP may refer to: Lighting * Oil lamp, using an oil-based fuel source * Kerosene lamp, using kerosene as a fuel * Electric lamp, or light bulb, a replaceable component that produces light from electricity * Light fixture, or li ...
, reflector and
lens A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements''), ...
assembly. Different mounting positions for the lamp (axial, base up, base down), different sizes and shapes of reflector and the nature of the lens (or lenses) being used can all affect the pattern of light. Secondly, the specifics of how the lamp is focused affect its pattern. In ''
ellipsoidal reflector spotlight Ellipsoidal reflector spot (abbreviated to ERS, or colloquially ellipsoidal or ellipse) is the name for a type of stage lighting instrument, named for the ellipsoidal reflector used to collect and direct the light through a barrel that co ...
s (ERS)'' or ''profile spotlights'', there are two beams of light emitted from the lamp. When the cones of both intersect at the throw distance (the distance to the stage), the lamp has a sharply defined 'hard' edge. When the two cones do not intersect at that distance, the edge is fuzzy and 'soft'. Depending on which beam (direct or reflected) is outside the other, the pattern may be 'thin and soft' or 'fat and soft'. Lastly, a
gobo Gobo may refer to: Places * Gobō, Wakayama, a city located in Wakayama Prefecture, Japan ** Gobō Station, a railway station in the city * Gobo, Cameroon, a commune in Cameroon Plants * Gobō (''Arctium lappa''), a biennial plant * Gobo (bur ...
or break up pattern may be applied to ERSs and similar instruments. This is typically a thin sheet of metal with a shape cut into it. It is inserted into the instrument near its aperture. Gobos, or templates, come in many shapes, but often include leaves, waves, stars and similar patterns.


Focus, position, and hanging

The focus is where an instrument is pointed. The final focus should place the "hot spot" of the beam at the actor's head level when standing at the center of the instrument's assigned "focus area" on the stage. Position refers to the location of an instrument in the theater's
fly system A fly system, or theatrical rigging system, is a system of rope lines, blocks (pulleys), counterweights and related devices within a theater (structure), theater that enables a stage crew to fly (hoist) quickly, quietly and safely components suc ...
or on permanent pipes in front-of-house locations. Hanging is the act of placing the instrument in its assigned position. In addition to these, certain modern instruments are
automated Automation describes a wide range of technologies that reduce human intervention in processes, namely by predetermining decision criteria, subprocess relationships, and related actions, as well as embodying those predeterminations in machines ...
, referring to motorized movement of either the entire fixture body or the movement of a mirror placed in front of its outermost lens. These fixtures and the more traditional follow spots add direction and motion to the relevant characteristics of light. Automated fixtures fall into either the "moving head" or "moving mirror/scanner" category. Scanners have a body which contains the lamp, circuit boards, transformer, and effects (color, gobo, iris etc.) devices. A mirror is panned and tilted in the desired position by pan and tilt motors, thereby causing the light beam to move. Moving head fixtures have the effects and lamp assembly inside the head with transformers and other electronics in the base or external ballast. There are advantages and disadvantages to both. Scanners are typically faster and less costly than moving head units but have a narrower range of movement. Moving head fixtures have a much larger range of movement as well as a more natural inertial movement but are typically more expensive. The above characteristics are not always static, and it is frequently the variation in these characteristics that is used in achieving the goals of lighting. Stanley McCandless was perhaps the first to define controllable qualities of light used in theater. In ''A Method for Lighting the Stage'', McCandless discusses ''color'', ''distribution'', ''intensity'' and ''movement'' as the qualities that can be manipulated by a lighting designer to achieve the desired visual, emotional and thematic look on stage. The
McCandless method Stanley Russell McCandless (May 9, 1897 – August 4, 1967) is considered to be the father of modern lighting design. He paved the way for future lighting designers by making contributions to almost all aspects of theatrical lighting, from t ...
, outlined in that book, is widely embraced today. The method involves lighting an object on the stage from three angles—2 lights at 45 degrees to the left and right, and one at 90 degrees (perpendicular to the front of the object). An alternative formulation is by Jody Briggs, who calls them ''Variable of Light'': Angle, Color, Intensity, Distance, Texture, Edge-quality, Size, and Shape.


Lighting professionals


Lighting designer

A lighting designer (LD) is familiar with the various types of lighting instruments and their uses. In consultation with the
director Director may refer to: Literature * ''Director'' (magazine), a British magazine * ''The Director'' (novel), a 1971 novel by Henry Denker * ''The Director'' (play), a 2000 play by Nancy Hasty Music * Director (band), an Irish rock band * ''D ...
, the DSM (deputy stage manager) and the scenic designer, and after observing
rehearsal A rehearsal is an activity in the performing arts that occurs as preparation for a performance in music, theatre, dance and related arts, such as opera, musical theatre and film production. It is undertaken as a form of practising, to ensure t ...
s, the LD creates an instrument schedule and a light plot as well as informing the DSM where each LX (lighting) cue is designed to be triggered in the script, which the DSM notes down in their plot book. The schedule is a list of all required lighting equipment, including color gel, gobos, color wheels, barndoors and other accessories. The light plot is typically a
plan view In technical drawing and computer graphics, a multiview projection is a technique of illustration by which a standardized series of orthographic projection, orthographic two-dimensional pictures are constructed to represent the form of a three-di ...
of the theatre where the performance will take place, with every luminaire marked. This typically specifies the approximate lighting focus and direction, a reference number, accessories, the address number (assigned DMX addresses) in the
dimmer A dimmer is a device connected to a light fixture and used to lower the brightness of the lighting, light. By changing the voltage waveform applied to the lamp, it is possible to lower the luminous intensity, intensity of the light output. Alt ...
system and channel on the
lighting control console A lighting control console (also called a lightboard, lighting board, or lighting desk) is an electronic device used in theatrical lighting design to control multiple stage lights at once. They are used throughout the entertainment industry and a ...
. A lighting designer must satisfy the requirements set forth by the director or head planner. Practical
experience Experience refers to conscious events in general, more specifically to perceptions, or to the practical knowledge and familiarity that is produced by these conscious processes. Understood as a conscious event in the widest sense, experience involv ...
is required to know the effective use of different lighting instruments and
color Color (American English) or colour (British English) is the visual perceptual property deriving from the spectrum of light interacting with the photoreceptor cells of the eyes. Color categories and physical specifications of color are associ ...
in creating a design. Many designers start their careers as lighting technicians. Often, this is followed by training in a
vocational A vocation () is an occupation to which a person is especially drawn or for which they are suited, trained or qualified. People can be given information about a new occupation through student orientation. Though now often used in non-religious c ...
college or
university A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United States, t ...
that offers theatre courses. Many jobs in larger venues and productions require a degree from a
vocational school A vocational school is a type of educational institution, which, depending on the country, may refer to either secondary or post-secondary education designed to provide vocational education or technical skills required to complete the tasks ...
or college in theatrical lighting, or at least a bachelor's degree.


Other positions

In theater: * Master electrician/chief electrician * Production electrician * Lighting programmer *Lighting operator/
light board operator The light board operator (commonly referred to as the "Light Op" or "Board Op") or moving light programmer, is the electrician who operates and/or programs the light board. Depending on the scale and type of production, the board op may be respons ...
In film: * Best boy (electrical) * Gaffer


Lighting equipment


Lighting instruments

In the context of lighting design, a lighting instrument (also called a ''luminaire'' or ''lantern'') is a device that produces controlled lighting as part of the effects a
lighting designer In theatre, a lighting designer (or LD) works with the director, choreographer, set designer, costume designer, and sound designer to create the lighting, atmosphere, and time of day for the production in response to the text while keeping ...
brings to a show. The term ''lighting instrument'' is preferred to ''light'' to avoid confusion between light and light sources. There are a variety of instruments frequently used in the theater. Although they vary in many ways they all have the following four basic components in one form or other: * Box/Housinga metal or plastic container to house the whole instrument and prevent light from spilling in unwanted directions. * Light source (
lamp Lamp, Lamps or LAMP may refer to: Lighting * Oil lamp, using an oil-based fuel source * Kerosene lamp, using kerosene as a fuel * Electric lamp, or light bulb, a replaceable component that produces light from electricity * Light fixture, or li ...
). * Lens or openingthe gap in the housing where the light is intended to come out. * Reflectorbehind or around the light source in such a way as to direct more light towards the lens or opening. Additional features will vary depend on the exact type of fixture. Most theatrical light bulbs (or ''lamps'', the term usually preferred) are tungsten-halogen (or quartz-halogen), an improvement on the original incandescent design that uses a halogen gas instead of an inert gas to increase lamp life and output. Fluorescent lights are infrequently used other than as worklights because, although they are far more efficient, they are expensive to make ''dimmed'' (run at less than full power) without using specialised dimmer ballasts and only very expensive models will dim to very low levels. They also do not produce light from a single point or easily concentrated area, and usually have a warm-up period, during which they emit no light or do so intermittently.
Scenic Art for the Theatre by Susan Crabtree and Peter Beudert.
However, fluorescent lights are being used more and more for special effects lighting in theaters.
High-intensity discharge lamp High-intensity discharge lamps (HID lamps) are a type of electrical gas-discharge lamp which produces light by means of an electric arc between tungsten electrodes housed inside a translucent or transparent fused quartz or fused alumina arc tu ...
s (or HID lamps), however, are now common where a very bright light output is required—for example in large follow spots,
hydrargyrum medium-arc iodide Hydrargyrum medium-arc iodide (HMI) is the trademark name of Osram's brand of metal-halide gas discharge medium arc-length lamp, made specifically for film and entertainment applications. ''Hydrargyrum'' comes from the Greek name for the eleme ...
(HMI) floods, and modern automated fixtures.
Interior Graphic Standards by Corky Binggeli and Patricia Greichen p. 558
When dimming is required, it is done by mechanical dousers or shutters, as these types of lamps also cannot be electrically dimmed. Over the last six years, LED-based luminaires of all varieties and types have been introduced to the market. Some of these fixtures have become very popular, whereas others have not been able to match the output from incandescent and discharge sources that lighting designers prefer. LED fixtures are making a positive impact on the lighting market, and are becoming more popular when compared to the energy usage of current incandescent, halogen, and discharge sources. Most instruments are suspended or supported by a "U" shaped ''yoke'', or '
trunnion A trunnion (from Old French "''trognon''", trunk) is a cylindrical protrusion used as a mounting or pivoting point. First associated with cannons, they are an important military development. Alternatively, a trunnion is a shaft that positions a ...
arm' fixed to the sides of the instrument, normally near its
center of gravity In physics, the center of mass of a distribution of mass in space (sometimes referred to as the balance point) is the unique point where the weighted relative position of the distributed mass sums to zero. This is the point to which a force ma ...
. On the end of such, a clamp (known as a hook-clamp, C-clamp, or pipe clamp—pipe referring to
battens A batten is most commonly a strip of solid material, historically wood but can also be of plastic, metal, or fiberglass. Battens are variously used in construction, sailing, and other fields. In the lighting industry, battens refer to lin ...
) is normally fixed, made in a "C" configuration with a screw to lock the instrument onto the pipe or batten from which it is typically hung. Once secured, the fixture can be panned and tilted using tension adjustment knobs on the yoke and clamp. An adjustable c-wrench, ratchet (US) or spanner (UK) is often used to assist the
technician A technician is a worker in a field of technology who is proficient in the relevant skill and technique, with a relatively practical understanding of the theoretical principles. Specialisation The term technician covers many different speciali ...
in adjusting the fixture.
Stage Lighting Primer
Most venues require an additional metal safety cable or chain to be attached between the fixture and its truss, or other string support anchorage. Some larger fixtures can weigh over and are suspended very high above performers heads, and could cause serious injury or death if they fell by accident or due to incorrect attachment. In the event of failure, the cable would halt the fall of the fixture before it could cause serious damage or injury. Many venues place strict guidelines regarding the use of safety cables.Connecticut College Theater Services Hazard Communication Guide
, Please see 'Lights' section.
The entire lighting apparatus includes the lights themselves, the physical structure which supports them, the cabling, control systems,
dimmer A dimmer is a device connected to a light fixture and used to lower the brightness of the lighting, light. By changing the voltage waveform applied to the lamp, it is possible to lower the luminous intensity, intensity of the light output. Alt ...
s, power supplies, and the
light board A lighting control console (also called a lightboard, lighting board, or lighting desk) is an electronic device used in theatrical lighting design to control multiple stage lights at once. They are used throughout the entertainment industry and a ...
s. (lighting console) Hanging the
light Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 tera ...
s or hanging the battons to hang the lights is known as 'rigging'.


Types of lighting fixture

All lights are loosely classified as either ''floodlights'' (wash lights) or '' spotlights''. The distinction has to do with the degree to which one is able to control the shape and quality of the light produced by the instrument, with spotlights being controllable, sometimes to an extremely precise degree, and floodlights being completely uncontrollable. Instruments that fall somewhere in the middle of the spectrum can be classified as either a spot or a flood, depending on the type of instrument and how it is used. In general, spotlights have lenses while floodlights are lensless, although this is not always the case. Within the groups of "wash" and "spot" light, there are other, more specific types of fixtures. This nomenclature also changes across the world depending on location and industry. ; Profile : These fixtures feature a compound lens which allows the designer to place obstructions within the image path which are then projected. These obstructions could be "gobos" or shutters. A profile is a spot light, but allows for precise focusing. This term is mostly used in the United Kingdom, Australia, and Europe, as ''profile spots'' in the United States and Canada are referred to as ''ERS'', ''ellipsoidals'', or just ''Lekos'', from the original
Lekolite A Lekolite (often abbreviated to Leko) is a brand of ellipsoidal reflector spotlight (ERS) used in stage lighting which refers to the half- ellipsoidal dome reflector within which the instrument's lamp is housed. Introduced in 1933, it was deve ...
created by Joseph Levy and
Edward Kook Edward F. Kook (1903–1990) was an American stage lighting engineer who helped to develop the art form, receiving a Special Tony Award for his contributions in 1952. He was a lecturer in it at two Ivy League universities, Columbia University and Y ...
, founders of Century Lighting, in 1933. ; Fresnel : A Fresnel or
Fresnel lantern A Fresnel lantern (pronounced ''frəˈnɛl or fruh-nel'') is a common lantern used in theatre that employs a Fresnel lens to wash light over an area of the stage. The lens produces a wider, soft-edged beam of light, which is commonly used for bac ...
is a type of wash light and is named as such due to the
Fresnel lens A Fresnel lens ( ; ; or ) is a type of composite compact lens developed by the French physicist Augustin-Jean Fresnel (1788–1827) for use in lighthouses. It has been called "the invention that saved a million ships." The design allows the c ...
it features as the final optical device within the chain. Traditionally theatre and stage lighting has been of the "generic" type. These are lights which are focussed, geled, and then simply dimmed to give the effect the designer wants. In recent years the emergence of moving lights (or automated lights) has had a substantial impact of theatre and stage lighting. A typical moving light allows the designer to control the position, color, shape, size and strobing of the light beam created. This can be used for exciting effects for the entertainment or dancefloor use. Moving lights are also often used instead of having a large number of "generic" lights. This is because one moving light can do the work of several generics. In Australia and many other places, the lamps inside a theatrical fixture are referred to as ''bubbles''. In North American English, a bubble refers to the protrusion that occurs when one's body (or other oily substance) contacts the lamp. Heat will cause the portion of the lamp which has oil on it to expand when it is on creating the bubble, and causing the lamp to explode. That is why one should never directly touch the glass portion of a lamp. Cleaning with
rubbing alcohol Rubbing alcohol is either an isopropyl alcohol or an ethanol-based liquid, with isopropyl alcohol products being the most widely available. The comparable ''British Pharmacopoeia'' (''BP'') is surgical spirit. Rubbing alcohol is denatured and un ...
will remove the oil.


Lighting controls

Lighting control tools might best be described as anything that changes the quality of the light. Historically this has been done by the use of intensity control. Technological advancements have made intensity control relatively simple - solid state dimmers are controlled by one or more lighting controllers. Controllers are commonly lighting consoles designed for sophisticated control over very large numbers of dimmers or luminaires, but may be simpler devices which play back stored sequences of lighting states with minimal user interfaces. Consoles are also referred to as lighting desks or light-boards. For larger shows or installations, multiple consoles are sometimes used together and in some cases lighting controllers are combined or coordinated with controllers for sound, automated scenery, pyrotechnics and other effects to provide total automation of the entire show, using a specific branch of MIDI technology called MSC (MIDI show control). See
show control Show control is the use of automation technology to link together and operate multiple entertainment control systems in a coordinated manner. It is distinguished from an entertainment control system, which is specific to a single theatrical depart ...
. The lighting controller is connected to the dimmers (or directly to automated luminaires) using a control cable or wireless link (e.g.
DMX512 DMX512 is a standard for digital communication networks that are commonly used to control lighting and effects. It was originally intended as a standardized method for controlling stage lighting dimmers, which, prior to DMX512, had employe ...
) or network, allowing the dimmers which are bulky, hot and sometimes noisy, to be positioned away from the stage and audience and allowing automated luminaires to be positioned wherever necessary. In addition to DMX512, newer control connections include RDM (remote device management) which adds management and status feedback capabilities to devices which use it while maintaining compatibility with DMX512; and
Architecture for Control Networks Architecture for Control Networks (ACN) is a suite of network protocols for control of entertainment technology equipment, particularly as used in live performance or large-scale installations. For example, lighting, audio or special effects eq ...
(ACN) which is a fully featured multiple controller networking protocol. These allow the possibility of feedback of position, state or fault conditions from units, whilst allowing much more detailed control of them.


Dimming

A dimmer is a device used to vary the average voltage applied to an instrument's lamp. The brightness of a lamp depends on its
electric current An electric current is a stream of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is measured as the net rate of flow of electric charge through a surface or into a control volume. The moving pa ...
, which in turn depends on the applied lamp voltage. When the applied voltage is decreased, a lamp's electric current will also decrease, thus reducing the light output from the lamp (dimming it). Conversely, a higher voltage will cause higher lamp current and increased (brighter) light output. Dimmers are frequently found in large enclosures called ''racks'' or ''dimmer racks'' that draw significant
three-phase power Three-phase electric power (abbreviated 3φ) is a common type of alternating current used in electricity generation, transmission, and distribution. It is a type of polyphase system employing three wires (or four including an optional neutral ...
. They are often removable modules that range from 20-ampere, 2.4- kilowatt to 100-ampere units. In the case of incandescent lamps, some color changes occur as a lamp is dimmed, allowing for a limited amount of color control through a dimmer. Fades (brightness transitions) can be either UP or DOWN, meaning that the light output is increasing or decreasing during the transition. Most modern dimmers are solid state, though many mechanical dimmers are still in operation. In many cases, a dimmer can be replaced by a ''constant power module'' (CPM), which is typically a 20- or 50-ampere breaker in a dimming module casing. CPMs are used to supply line voltage to non-dimming electrical devices such as smoke machines, chain winches, and scenic motors that require constant operating voltage. When a device is powered by a CPM, it is fully energized whenever the CPM is turned on, independent of lighting console levels. CPMs must be used (in lieu of dimmers) to power non-dimming devices that require specific line voltages (e.g. in the US, 120 V, 60 Hz power) in order to avoid damage to such devices. Dimmers are seldom used to control non-dimming devices because even if a dimmer channel is trusted to always operate at full power, it may not be controlled when communications are disrupted by start up and shut down of the lighting control surface, noise interference, or DMX disconnects or failure. Such a loss of control might cause a dimmer to dim a circuit and thus potentially damage its non-dimming device. Devices like moving heads also require independent power, as they cannot function on a partially dimmed channel for power, on top of requiring several other channels in order to convey all of the data they require for their several features. In order to simplify the control of moving head lanterns, instead of assigning channels manually to the lantern, many desks also offer a fixtures section, where one can assign the lantern as a fixture, allowing the desk to organise the data being transferred to the lantern on a much simpler scale for the operator. Fixtures may also incorporate smoke machines, snow machines, haze machines etc., allowing many special effects to be run from a single desk. Increasingly, modern lighting instruments are available which allow remote control of effects other than light intensity, including direction, color, beam shape, projected image, and beam angle. The ability to move an instrument ever more quickly and quietly is an industry goal. Some automated lights have built-in dimming and so are connected directly to the control cable or network and are independent of external dimmers.


See also

* DJ lighting *
Gas lighting Gas lighting is the production of artificial light from combustion of a gaseous fuel, such as hydrogen, methane, carbon monoxide, propane, butane, acetylene, ethylene, coal gas (town gas) or natural gas. The light is produced either directl ...
*
High-key lighting High-key lighting is a style of lighting for film, television, or photography that aims to reduce the lighting ratio present in the scene. This was originally done partly for technological reasons, since early film and television did not deal w ...
*
Low-key lighting Low-key lighting is a style of lighting for photography, film or television. It is a necessary element in creating a chiaroscuro effect. Traditional photographic lighting ( three-point lighting) uses a key light, a fill light and a back light ...
* Tree lights


References


Further reading

* Bergman, Gösta, M (1977) ''Lighting in the Theatre'', Stockholm: Almqvist & Wiksell / Totowa, NJ: Rowman & Littlefield * Palmer, Richard H (1985) ''The Lighting Art: The Aesthetics of Stage Lighting Design''. Englewood Cliffs, New Jersey: Prentice-Hall, Inc. * Palmer, Scott (2013)
Light: Readings in Theatre Practice
', Basingstoke: Palgrave Macmillan * Penzel, Frederick (1978) "Theatre Lighting before Electricity". Middletown, CT: Wesleyan UP. * Pilbrow, Richard (1997) ''Stage Lighting Design: The Art, the Craft, the Life'',
Nick Hern Books Nick Hern Books is a London-based independent specialist publisher of plays, theatre books and screenplays. The company was founded by the former Methuen drama editor Nicholas Hern in 1988. History Nick Hern Books was founded in June 1988,Sara ...
, London. .


External links


Stage Lighting for Students
{{Artificial light sources