Lighting Training Terminology

Stagecraft 1 & 2 Mr. Megaro

Lighting Training – Terminology

Below are common terms used by Lighting people. . Amp . Focus . Moving (ampere) . Front of House Light . Circuit (FOH) . Patch . Convention . Gel . Programmi al . Gobo ng . Elli . Hang . Stage psoidal . House Left Directions . Fr . House Right . Stage Left esnel . Lamp . Stage Pin . PA . LED . Stage R can . Lens Right . Dimmer . Load . Twist Lock . DMX . Upstage . Downstage . Volt . Edison . Watt . Flash Amp

The measure of electrical current. In paper work it is referred to simply as an ‘a.’ So 20a is twenty amps. Circuits and ;Dimmers are rated to handle a specific amount of amps. It is necessary have a safety buffer of at least 20% (example: 4a of 20a circuit) when calculating loads. It is also beneficial to know that it’s the amps that kill you. In the power equation Amps = Watts / Volts. Back to glossary

Circuit

Simply, whatever a light or accessory plugs into is a circuit. It doesn’t matter if it is a dimmer, or a wall outlet. The term is also used to mean a particular electrical circuit, as in: “This outlet goes to circuit #4 in panel SB-1.” All dimmers are circuits. Back to glossary

Conventional

Any of several traditional fixtures. Sometimes referred to as ‘generics’ consoles can only control their intensities. Usually these fixtures can be dimmed and fitted with a number of accessories. Back to glossary Dimmer

There are multiple kinds of dimmers but in event and theatrical lighting with SCR (silicon controlled rectifier) dimmers being most common. TV studios and other specific applications make use of IGTB (insulated gate bipolar transistors) dimmers which are far more expensive. These units allow lamps to run at different intensities. To control dimmers with DMX, the dimmer must be cabled to the console and addressed and patched properly. A useful article on SCR v. IGTB dimmers can be found here. Back to glossary

Short for Digital MultipleX, this is the standard language of lighting control. A very robust signal sent along three wires, DMX can have up to 512 separate channels and some consoles are built to control multiple ‘universes’ of DMX. Each parameter of each light takes up one channel. So a conventional light takes one channel (intensity) whereas a moving light takes many more (pan course, pan fine, shutter, strobe, zoom, color wheel, etc). DMX cables are either 3 pin or 5 pin and have a different resistance than audio cable and therefore should not be mixed up. For more information on DMX here is a primer Back to glossary

Downstage

The area of the stage that is closest to the audience. It can also refer to a relative location as in “He is more downstage than the drum riser” For more information about Stage Directions please see http://en.wikipedia.org/wiki/Stage_directions#Stage_directions or http://en.wikipedia.org/wiki/Rake_theatre and Stage Directions.

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Edison Edison male and female connectors Edison (sometimes referred to as PBG or parellel blade ground or household plug) is a reference to a specific connector. This is the connector used in your home and business. Often fixtures that are not dimmable use Edison plugs as a way to differeante them. Back to glossary

Ellipsoidal

Short for Ellipsoidal Reflector Spotlight (ERS), these fixtures create light with hard edges, suitable for pattern projection. Other names include ‘leko’ or ‘Source4′ which are brand names. Features of this light can include shutters, gobo slots, rotating barrels and interchangeable lenses. Often used as front light and side light these lights with some diffusion gel can create extremely even washes for IMAG or recording purposes. Back to glossary

Testing of a fixture is referred to as flashing. Usually flashing is done before a light is hung, so that any troubleshooting is easier. If possible flash every possible parameter before hanging. Back to glossary

Focus is where a light is directed. When making a plot, the area to be lit is broken up into focus areas. Different events and spaces create different focus needs. When time is devoted to aiming lights, this is also known as focus. Focus is also a synonym for dinner break. Back to glossary

Fresnel Pronounced Fer-nell, this lens is designed for even diffuse washes of light. A fixture of this type will include a manual spot/flood function to zoom in/out the size of the beam. Useful for diffused washes of light, as well as excellent top light. Back to glossary

Front of House (FOH)

In theaters and live music venues, Front of House (or FOH) refers to areas of the building that the audience has access to, generally excluding stage and backstage areas, and including the auditorium and foyer. Basically where the public has access to. This term is also associated with the location of both lighting and the sound board generating the FOH mix. For more information about Stage Directions please see http://en.wikipedia.org/wiki/Stage_directions#Stage_directions or http://en.wikipedia.org/wiki/Rake_theatre and Stage Directions.

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Sometimes referred to as filters, media or simple color, gel is used to change the color of the light. The name comes from a time when it was actually made out of gelatin, nowadays it is made out of polyester. Except for dichroics, deep dyed glass and Permacolor all gel will eventually burn out (lose it’s color). The speed of burn out depends on how much use a light gets and how saturated the color is. A swatch book of a companie’s gels is available (usually for free) from dealers. Gel companies include Rosco, Lee, Apollo and GAM. Remember when picking color from a swatch book to look at the color through a light and not at the media itself. Back to glossary Gobo

Short for GOes Before Optics. They are made of either metal or glass (glass ones can come in multiple colors). Used in fixtures that create a hard edge beam (ERS, spots, sealed beam, etc) to create texture. Also known as patterns, gobos are sometimes used to created specific representational images, (clouds, windows, signs). Some patterns, called break up are used to create the feeling of highly disorganized light (as in a jungle under the canopy). Gobos are choosen for one or a combination of reasons, 1) how they look projected on a surface, 2) how people or object look under them or 3) how they look when used in conjuction with haze. There are many stock gobos available from various companies including Rosco (they also have an iPhone app) and Apollo. Custom gobos are also available from either company. Back to glossary Hang This is a general term for setting up lighting. Technically this term only refers to placing fixtures in their specific locations but can also mean cabling (running any necessary extensions required to plug a light into a dimmer or circuit). Back to glossary House Left

This refers to the left side of the house/audience, as one is sitting in the audience, facing the stage. For more information about Stage Directions please see http://en.wikipedia.org/wiki/Stage_directions#Stage_directions or http://en.wikipedia.org/wiki/Rake_theatre and Stage Directions.

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House Right

Refers to the Right side of the house/audience, as one is sitting in the audience, facing the stage. For more information about Stage Directions please see http://en.wikipedia.org/wiki/Stage_directions#Stage_directions or http://en.wikipedia.org/wiki/Rake_theatre and Stage Directions.

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Lamps are the generally called ‘bulbs’ in the non lighting world (or ‘globes’ in the film world). There are many types and wattages and each fixture can only use very specific ones. Refer to instrument user manuals on appropriate lamps or to our internal wiki. A lamp breaks down into three parts: the base, the filament, and the envelope. The base secures the lamp into the socket. The filament is the resistor in the circuit that produces light (except in lights where an open arc occurs). The envelope or bulb contains the filament and various gases required to create light. Most theatrical lamps have envelopes that you cannot touch with your hand. If skin comes in contact with the lamp, wipe off the envelope with rubbing alcohol and a clean cloth. The oil from your skin will heat (and therefore expand) at a different rate then the rest of the envelope. This will cause an explosion if the lamp is turned on. Back to glossary

LED stands for Light Emitting Diode and can refer to specific LEDs in a light or to a fixture made up of LEDs. Generally LEDs are much brighter per Watt than other lamps (although Lifi’s may give LEDs some competition), and last much longer (compare 500 – 4000 hours of lamp life for various theatrical lamps to a minimum 10,000 hours for LEDs). LED fixtures are almost exclusively used for wash purposes, though a few options exist with focusable beams. Fixtures made up of LEDs generally consist of multiple colors mixed together such as Red, Green, Blue (RGB) sometimes with addition of Amber or White LEDs. There are also LED fixtures that exist for white light applications that are made up different whites at different color temperatures. Back to glossary

Lenses are made of shaped glass and are used to manipulate light. Most conventional fixtures are named in part by their lens. Lenses can even out the quality of the light or give light a focus-able edge suitable for gobo projection. Lens cleaning should be a part of fixture maintenance. Back to glossary

Load Load refers to the amount of draw on a circuit. All circuits, cables, connectors, and fuses are rated for particular loads (20a or 2400w, 15a or 1800w, etc) and it is important to know what load you are putting on a circuit. Most lamps will have their load printed on them (and if they are new or barely used, you might be able to read it), moving lights and accessories will have their loads’ spec-ed in their user manuals. If non-lighting equipment is being plugged into circuits most will have their loads listed near their plug. It is critical to not overload cables and connectors because they are not protected like circuit breakers and could start a fire. Knowing your load will keep you from popping circuit breakers. If you make a habit of not watching loads you will wear out circuit breakers and they will lose capacity on the circuit over time. Back to glossary

Moving Lights

Also known as movers, automated, automated lighting, automated luminaire and wigglers. There are two types of movers: moving head (or moving yokes) and moving mirrors (or scanners). From here they further break down into spot/profile fixtures, wash and beam lights. Spots have a convex lens and can produce hard edged beams suitable for gobos. Wash lights generally have a Fresnel lens and have diffused beams. Some fixtures refer to themselves as ‘hybrids’ and try to have both spot and wash options available to the user, whether through interchangeable lenses (ex. Martin SmartMAC) or advanced frost filter within the fixture (ex. Elation 1200c). Beam fixtures have almost no beam angle, think search lights. Most moving lights have more parameters than just pan, tilt and intensity. Color wheels, color mixing, gobos, animation wheels, iris, shutters, strobes, etc are available depending on the type and quality of the fixture you purchase. It is good to note that there is nothing a moving light can do that a conventional light with an accessory or two can’t. For example color changing in an Ellipsoidal can be attained through adding a Color Scroller or SeaChanger. Back to glossary

PAR can

Parabolic Aluminized Reflector cans come in multiple sizes from PAR16s to PAR64s. Each size has their own lamp and wattages. Until recently the lamp and lens were one piece, and you chose your wattage and your beam at the same time. Lamps came in Very Narrow (VNSP) to Very Wide (VWFL). These inexpensive and rugged lights are still very common although several manufacturers have developed PARs that are have separate lamps and lenses. Unlike most lights, they do not produce a circle of light, but rather a parabola, which can be rotated (sometimes called ’spinning the bubble’) for better wash lighting. Back to glossary Patch

Patch or patching is connecting two pieces together. There is the hard patch: fixtures into circuits, circuits into dimmers, DMX into universes. There is also the soft patch: fixtures addressed within the console. A Patch can also refer to all associated paperwork. Back to glossary

Programming

Any preparation of lighting consoles or computers is known as programming. Whether you write entire services or events into a complicated series of cues, chases and macros or merely group a few conventionals together, it’s programming. Back to glossary

Stage Directions

A way of defining locations on the stage which are universally accepted. Various directions include Stage Left, Stage Right, Upstage, Downstage, House Left, House Right, Proscenium or Proscenium Arch, wings, and Front of House (FOH). For more information about Stage Directions please see http://en.wikipedia.org/wiki/Stage_directions#Stage_directions or http://en.wikipedia.org/wiki/Rake_theatre Back to glossary

Stage Left

Refers to the Left side of the stage as one is standing on the stage, facing the audience. It can also be used as a directional reference as in “move this stage left four feet.” For more information about Stage Directions please see http://en.wikipedia.org/wiki/Stage_directions#Stage_directions or http://en.wikipedia.org/wiki/Rake_theatre and Stage Directions.

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Stage Pin Stage Pin Sometimes called Ground Stage pin, this particular connector is not widely in use at Mars Hill but it is a very common connector in the lighting world. If you rent lighting equipment, it is very possible the vendor’s gear is in stage pin. This is very common in the world of theatre because it is extremely economical and it is a useful way to differentiate between dimmable and non-dim circuits. Back to glossary

Stage Right

Refers to the Right side of the stage as one is standing on the stage, facing the audience. It can also be used as a directional reference as in “move this stage Right four feet.” For more information about Stage Directions please see http://en.wikipedia.org/wiki/Stage_directions#Stage_directions or http://en.wikipedia.org/wiki/Rake_theatre and Stage Directions.

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Twist Lock Various Twist Lock Style Connectors A style of connector widely used at permanent campuses. Named because after inserting the connector, a small turn keeps the male and female together. Obviously this is one of the most secure connection available without the use of tape or tie-line. Generally it is a more expensive connector, but by having dimmers and other lighting specific power sources built with twist lock other departments are less likely to unintentionally plug in equipment where it doesn’t belong. Back to glossary

Upstage

The area of the stage that is furthest from the audience. It can also refer to a relative location as in “the drum riser is upstage from the guitar amp” For more information about Stage Directions please see http://en.wikipedia.org/wiki/Stage_directions#Stage_directions or http://en.wikipedia.org/wiki/Rake_theatre and Stage Directions. Back to glossary

Represented by the letter ‘v’, volts (or voltage) generally comes in two varieties as far as lighting is concerned: 120v or 208v. In the water analogy volts are the measure of the force. Different equipment is rated for different voltages. It important to know what kind of voltage each part of your equipment can handle (the fixture, the fixture’s lamp, the connector, the cable, etc) before plugging it in. Most common connectors are pretty specific about their voltage to help avoid confusion. Some equipment is able to handle more than one voltage but may need adjustments before switching the voltage you are giving it. Back to glossary

The amount of energy used over time. Specifically in dealing with electricity it is the amount of ‘apparent power’ in circuit. The shorthand for Watts is a ‘w’ (575w is five-hundred and seventy-five watts). In the power equation Watts = Amps * Volts. (Technically this is only true of DC applications, in AC applications a power factor has to be added in. Rule of thumb: leave 20% extra in any circuit and this will cover most situations.) Generally lamps are measured in Watts. Back to glossary