Colour additive and subtractive mixing
Colour mixing is combining the effects of two or more lighting gels and can be either subtractive or additive:
- Subtractive- placing two different gels in front of the same lantern. Subtractive mixing is used to obtain a colour effect that is not available from stock or from manufacturers, although the wide range of available colours is so wide that the need for subtractive mixing is reducing. Combining colours in this way reduces the light towards blackness. The three primary colours of light (Red, Green and Blue) mix subtractively to form black (or to block all the light).
- Additive- focusing two differently coloured beams of light onto the same area (eg. Cyc Floods). Combining colours in this way adds the colours together, eventually arriving at white. The three primary colours additively mix to form white, as do the complementary colours. See Light Theory and Light Mixing .
Lighting Designer
The role of the lighting designer within theatre is to work with the director, set designer, costume designer, and sometimes the sound designer and choreographer to create an overall 'look' for the show in response to the text, while keeping in mind issues of visibility, safety and cost. The LD also works closely with the stage manager on show control programming, if show control systems are used in that production. Outside of the theatre the job of a Lighting Designer can be much more diverse and they can be found working on rock and pop tours,corporate launches, art installation and on massive celebration spectaculars, for example the Olympic Games opening and closing ceremonies.
Lighting Operator
Lighting operators position, set up and operate lighting equipment to light sets or studios during stage performances, television broadcasts or film productions. Lighting operators are responsible, both creatively and technically, for lighting interior and outside scenes and must achieve the desired effects through the placement, intensity and colour of lighting.
Lighting operators may perform the following tasks:
- study scripts and discuss lighting effects with production staff
- coordinate activities with electrical crew when putting up metal scaffolding to support lighting equipment
- select and position equipment such as spotlights and floodlights
- arrange and connect cables to electrical supply using portable junction boxes
- operate lights during filming or broadcasting and vary intensity of light using various filters and reflective screens
- maintain and repair lighting equipment
- arrange for transportation of equipment to remote locations.
Follow Spot Operator
A Followspot Operator is a theatrical technician, defined as a lighting technician, who operates a specialised stage lighting instrument known as a followspot. A followspot is designed to move, change size, beam width, and color easily by hand. Followspotting is often seen as the apprentice role for new technicians, especially electricians, and having the role is occasionally referred to by some members of the run crew as being "a limey", a term derived from limelight.
Lighting Technician
Lighting technicians are involved with rigging and controlling electric lights for art and entertainment venues (theater or live music venues) or in video, television, or film production. In a theater production, lighting technicians work under the lighting designer and master electrician. In video, television, and film productions, lighting technicians work under the direction of the cinematographer and gaffer. In live music, lighting technicians work under the chief lighting technician, who reports to the production manager.
Lighting technicians are responsible for the movement and set up of various pieces of lighting equipment for visual effects. Lighting Technicians may also lay electrical cables, wire fixtures, install color effects or image patterns, focus the lights, and assist in creating effects or programming sequences.
Reference
Key terms and concepts
3 phase power
Electricity is generated and supplied to large installations in three phases. The Red, Yellow and Blue phases are all supplied down one cable to the building but effectively give three separate supplies. This is usually the power supply for dimmer racks in a theatre lighting system.
Cables
All electrical components in a lighting, sound or AV system are interconnected with cables - wiring which has been temporarily rigged to carry electrical current. Depending on the size of the cable (current carrying capacity), cables are used to supply individual lanterns, whole dimmer racks, or carry signals from a microphone etc.
Career pathways
This refers to the different areas of production and the levels of responsibility/creativity in each area. The main areas of work in lighting include live theatre and events such as rock concerts etc. and television and film lighting. The levels of responsibility range from lighting hand and lighting technician to lighting operator and lighting designer.
Cleaning, maintenance and storage of light equipment and accessories
Obviously maintenance and storage of lighting equipment is critical to its efficient use. Lanterns and their accessories should be cleaned regularly as dust build-up on the lens is one of the most frequent reasons for inefficient light operation. Lanterns and accessories should be stored in a clean and dry place and all items should be tested regularly.
Colour call sheets
These are lists compiled from the lighting plan of all the colours needed for the rig, and their size. This term also applies to the act of preparing colour filters and frames from these lists.
Communication
Usually referred to as “Comms”, communication systems used by lighting personnel are usually two-way ‘radio’ or wired systems designed so that each person can listen and speak to every other person using the system. Wired systems are often called a “Comms ring” as they are set up in a series or a loop of devices connected one after the other.
Dimmers
Dimmers are the electrical or electronic devices which control the amount of electricity passed to a lantern, and therefore the intensity of the lamp. Dimmers are like active transformers, responding to the levels sent to them from lighting consoles and passing those levels on to lanterns. Dimmers are often grouped together into a cabinet or housing of some sort and called a “dimmer rack”.
Documentation
Documentation for lighting includes:
- lighting schedule - a list of available lanterns
- colour call sheets - a list of required colours
- lighting plan – a scale drawing detailing the exact location of each lantern used in a production as well as any other relevant information (eg its dimmer number, focus position and colour number). This is often drawn from the theatre’s groundplan.
Effects of colour
Depending on the context, this could refer to special lighting effects (gobos or strobe), special visual effects (fog machine or pyrotechnics) or sound effects (thunder, vocoder, smashing glass). It could also be audio devices designed to treat (effect) audio signals such as compressors, reverb units or equalisers.
Electrical safety
This refers to the precautions and safety measures taken when using electricity or electrical devices, so as to avoid danger, damage, injury or death. Wearing insulated shoes (with rubber soles) or using fibreglass or plastic ladders are two examples of precautions which can be taken.
Lamp types
There are several different types of lamp (domestically called a light bulb): incandescent bulbs, fluorescent bulbs, LEDs (Light Emitting Diodes) but all of them turn electrical energy into light (and almost invariably heat as well).
Licensing requirements
Licensing requirements most often refers to the ‘hire’ of the performance rights to a written/composed work for a set period of time and the strict adherence to obligations with regard to advertising, copyright and intellectual property. There are similar conditions applied to lighting devices.
Light beam accessories
These are devices added onto a lantern or inserted into a lantern that are used to alter or manipulate the beam of light emanating from the lantern.
Light theory
Light theory includes both the physics of light waves/beams/particles and the Additive and Subtractive theory of colour mixing . Colour mixing of light is different to colour mixing of pigments or paint. While the primary colours of paint and pigments are RED, YELLOW, BLUE, which, when mixed, tend towards black, the Primaries of Light are RED, GREEN, BLUE, which, when mixed tend towards white.
Secondaries of Light are Magenta (Purple), Cyan (Light Blue) and Amber (Yellow). (For more information see Light Mixing
Lighting components
There is a variety of common components in a lighting system including lanterns, dimmers, patch bays, lighting desks or boards. Other lighting components may include lighting bars, stands and accessories.
Lighting control systems
These include lighting boards, lighting desks, light controllers, DMX Controllers and any other device that is used to control the lanterns being used.
Lighting desk
This is the main control for the stage lighting. Originally known as the switchboard or dimmerboard, it is now usually remote from the dimmers. The lighting operator for a show is often said to be ‘on the board’ and is sometimes known as the ‘board op’. In the U.S. , the lighting desk is referred to as the light board.
Lighting equipment
This includes everything from the lanterns to dimmers, controllers, accessories such as colour frames, donuts, barn doors and gobos, cables, stands, lighting bars, safety chains, hooks, clamps, gels and bubbles.
Lighting operations
This refers to preparing for or undertaking the job of illuminating objects or changing lighting states.
Lighting personnel
This includes all people involved in lighting operations: lighting hands, lighting technicians, lighting operators, lighting designers and lighting directors.
Lighting plan
This is a scale drawing detailing the exact location of each lantern used in a production, as well as any other relevant information, such as its dimmer number, focus position and colour. The lighting plan is often based on the theatre’s ground plan.
Lighting schedule
This is a list of lanterns (and other components and accessories) available for use at a particular theatre or venue.
Lighting technician
This refers to a person with the knowledge, skill and expertise to rig, set up, replace lamps, focus and basically operate professional lighting equipment.
Occupational health and safety (OHS)
The relevant health and safety considerations for (in this case) lighting technicians include heat, height, weight, position and the electrical current of lanterns, their installation and operation.
Organisational procedures
These are procedures specific to an organisation which are used to ensure its proper running and appropriate administration. They may include safety audits, fire drills, maintenance audits, staff meetings, production meetings, bump in/bump out, technical rehearsals etc.
Patch location
This is the specific position or location of a device with particular reference to the patch panel or bay to which it is connected (usually a number).
Patching
This refers to the act of interconnecting devices in a (lighting) system, especially connecting lanterns to dimmers. Lighting circuits around the stage area can be cross-connected to a chosen dimmer, often using a cross-connect panel (sometimes called a patch bay or patch panel), which enables any stage lighting channels on the control desk to control any dimmer or group of dimmers. Some large lighting boards have the facility for soft patching - a totally electronic way of patching. Some rock desks have a pin patch which allows groups of dimmers to be allocated to a particular control channel.
Positioning point
This is the actual physical position in which a lantern is hung or placed in a theatre or venue, whether on bars, stands or on the stage or floor.
Production plan documentation
This refers to documents related to the preparation and planning of a production, including schedules, rosters, groundplans, site plans etc.
Reporting
This is related to the lines of communication and hierarchy of reporting within a team, crew, production company and/or enterprise or organisation. All workers should report to their immediate supervisor.
Rigging
This refers to the construction or arrangement of lighting equipment for a particular production as well as the act of installing lighting, (sound equipment and scenery etc.) for a particular show.
Safe work practices
Safe work practices require following correct OH&S procedures to ensure the safety of all workers doing their job. These include turning off power and disconnecting lanterns when installing or repairing units, using correct lifting techniques, wearing protective clothing, harnesses, shoes, gloves etc., as required, and ensuring appropriate noise, light and platform levels when working at height.
Subtractive and additive colour mixing
Colour mixing is combining the effects of two or more lighting gels and can be either subtractive or additive:
- Subtractive - placing two different gels in front of the same lantern. Subtractive mixing is used to obtain a colour effect that is not available from stock or from manufacturers, although the wide range of available colours is so wide that the need for subtractive mixing is reducing. Combining colours in this way reduces the light towards blackness. The three primary colours of light (Red, Green and Blue) mix subtractively to form black (or to block all the light).
- Additive - focusing two differently coloured beams of light onto the same area (eg. Cyc Floods). Combining colours in this way adds the colours together, eventually arriving at white. The three primary colours additively mix to form white, as do the complementary colours. See Light Theory and Light Mixing .
