STAGE LIGHTING INSTRUMENTS Parts, Maintenance, Safety, and Use

Learning Goals Learn the exterior and interior parts of a stage lighting instrument. Use the instrument as a learning tool: learn the practical and artistic uses of stage lighting. Use the instrument as a learning tool: learn what trades and fields of study go into the creation and use of stage instruments. Have a general concept of a) how the instrument works, b) how to maintain the instrument, and c) general safety measures for the instrument.

Lighting Lingo Stage lights are called “instruments.” The bulbs in instruments are called “lamps.” Putting an instrument up on the grid is called “hanging.” Plugging in the instrument to a circuit is called “patching.” Pointing an instrument in the appropriate direction, and adjusting the beam width and shape, are called “focusing.”

… an ETC Source Four ERS 750 (36˚). Parts of an Instrument To understand the parts of a lighting instrument, we will look at one of the most common examples… … an ETC Source Four ERS 750 (36˚).

Parts of an Instrument ETC Par Four 750 (36˚) means… ETC = Electronic Theatre Controls ® ERS = Ellipsoidal Reflector Spotlight 750 = Maximum Wattage Rating (750 watts) 36˚ = Field Angle (width of the cone of light at 10% intensity)

ETC Source Four ERS 750 (36˚)

C-Clamp (Pipe Clamp) Lamp Housing Yoke Reflector Housing Instrument Barrel (Lens Tube inside) Shutter Handle Power Cable (Pigtail) Gel Frame Holder Grand Stage Pin (GSP)

Now that you are acquainted with the parts of a stage lighting instrument, let’s see what different trades and fields of study go into its construction.

C-Clamp (Pipe Clamp) Lamp Housing Yoke Reflector Housing Instrument Barrel (Lens Tube inside) Shutter Handle Power Cable (Pigtail) Gel Frame Holder Grand Stage Pin (GSP)

Physics & Machining Electrical Engineering Physics, Machining, & Industrial Tech Machining & Industrial Tech HVAC Electrics & Energy Tech Visual Art, Color Theory, & Optics Electrical Engineering & Energy Tech

In other words… There’s a lot of “tech” in theatre technology.

Close-up of Grand Stage Pin

Close-up of Grand Stage Pin

Close-up of Lamp Housing (Rear View) Secures Lamp Housing Adjusts Angle & Position of Lamp (Bulb) within Housing

Close-up of Barrel and Gel Frame Holder SLIDER HANDLE: Adjusts edges of light “throw” GEL CLIP: Secures Gel Frame and Color Gel BEAM FOCUS KNOB: Adjusts sharpness of light edge GEL FRAME HOLDER: Holds Gel Frame and Color Gel in place

Interior of Lamp Housing

Interior of Lamp Housing

Interior of Lamp Housing Bolt secures lamp housing Lamp Clip Lamp (Bulb) Pigtail

Lamp (Bulb) LAMP Specs Watts: 750 Volts: 77-115 Amperage: 6.52 300 “life hours” (total hours of use at full intensity) Lumens: 23,000 Total length: 4 - 4.170 inches. Glass Shape: T Diameter of glass: 0.75 inches Base: G9.5 Heatsink (two pin) Filament Type: 4C8 (Tungsten) Gas around filament: Halogen Price (2017): about $17 to $25

Reflector Housing (exterior without lamp housing) C-Clamp Twist handle controls yoke position. Yoke

Rear of Instrument (interior without lamp housing) Glass portion of lamp (bulb) fits through here. Since a lamp (bulb) shines in all directions, the reflector redirects the light through the barrel and out the front of the instrument.

Shutter Operation = = = = shutters in “pulled” position “shuttered” Shape of light on flat surface “shuttered” light = = Shape of light on flat surface

Lens Tube and Inner Lens (from rear)

Interior of Lens Tube (with Inner and Outer Lenses) Gel Frame Holder Inner Lens FRONT OF BARREL Outer Lens

Instrument Components

Instrument Components

How Light Travels through the ERS Lighting Instrument Yellow lines with arrows = beams of light originating from lamp. Glass portion of LAMP REFLECTOR Wall of lens tube: both sides are black-painted metal (to reduce reflectivity) Wall of lens tube: both sides are black-painted metal (to reduce reflectivity) Large Plano Convex LENS Small Plano Convex LENS

Cleaning Instrument Exterior This is as simple as using canned air or a dry, soft washcloth!

Cleaning Instrument Interior (Metal Parts) This is (also) as simple as using canned air or a dry, soft washcloth!

Cleaning Instrument Lenses Take off rubber tabs (these secure the lens in the holding slots). Mix 3 parts water with 1 part white distilled vinegar. Submerge lens in mixture for a few moments. Wipe dry with a soft (NOT microfiber or paper) cloth. Check both sides of lens for smudges under a strong light. Remove smudges with cloth. Replace rubber tabs and reinsert lens into lens housing (aligning tabs with holding slots).

General Safety Precautions Follow general electricity precautions (e.g., never touch anything electrical with wet hands). Heat-resistant gloves are recommended. Even the exterior of an instrument becomes very hot within a few minutes! NEVER look directly into the lens of the light when less than 5 feet from it. NEVER look directly at a lamp that is on but not in the lamp housing! Violation of rules 3 and 4 can cause permanent damage to the retinas of your eyes. BEFORE you take both hands off the instrument, ALWAYS make sure a) the pipe clamp is fully tightened, and b) the safety cable is attached to both the instrument and the pipe or batten. 7) Always tie your wrench to your belt loop with theatrical tie-line.

The Instrument in Action Example of silhouette (back) lighting. Example of multidirectional, Overhead (top) lighting.

What can Stage Lighting do? PRACTICAL USES Indicate and separate locations. Hide or reveal people and objects. Show passage of time, time of day, season, beginning/end of scene or play. Project shadows. Create colors and shapes on surfaces. ARTISTIC USES Establish mood. Highlight aspects of plot. Indicate a character’s emotional state. Establish the “Fourth Wall” (division between the plot’s world and audience’s world).

Seasonal Lighting Effect: Winter Photo owned by Real Sound and Vision, Inc. Fair Use applies.

Mood Lighting Effect: Foreboding Production: Pittsburgh Repertory Theatre’s Nocturnal Wanderer by Gao Xingjian. Director: Paul “Spike” Wilson. Lighting Designer: Peter Fedyshin. Photo by: Heather Garmin

Lighting Effect: Plot Highlight (an abandoned shoe)

Lighting Effect: Location (basement tenement) Production: Miami University’s Two by Ron Elisha. Director: Paul “Spike” Wislon. Lighting Design: Jennifer Lee. Photo by Gion DeFrancesco

Mood Lighting Effect: Nostalgia (also partial Silhouette Effect) Production: Miami University’s Two by Ron Elisha. Director: Paul “Spike” Wilson. Lighting Design: Jennifer Lee. Photo by Gion DeFrancesco.

Resources The Theatrical Lighting Glossary http://www.alss1.com/rentalsproductions/glosslight.html “Lighting Instruments” in WPI Technical Theatre Handbook http://www.gweep.net/~prefect/pubs/iqp/technical_theatre_handbook.pdf Introduction to Stage Lighting: The Fundamentals of Theatre Lighting Design by Charles I. Swift. ISBN: 1566080983. Optics and Photonics: An Introduction by F. Graham Smith, et al. ISBN: 0470017848. The Stage Lighting Handbook by Francis Reid. 6th Edition. ISBN: 978-0878301478.