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Encyclopedia > Ellipsoidal
Source Four ERS
Source Four ERS

Ellipsoidal, or Ellipsoidal Reflector Spotlight (abbreviated to ERS), is the name for a type of theatrical light, getting the name from the ellipsoidal reflector used to intensify the light of a back-loading lamp through the barrel and lens. Ellipsoidals are used for their strong, well-defined light and their versatility. Leko and Source Four are brand names which may occasionally be used to refer to any sort of ellipsoidal. Image File history File linksMetadata Download high resolution version (1200x1600, 428 KB) Licensing I, the creator of this work, hereby release it into the public domain. ... Image File history File linksMetadata Download high resolution version (1200x1600, 428 KB) Licensing I, the creator of this work, hereby release it into the public domain. ... Modern stage lighting is a flexible tool in the production of theatre, dance, opera and other performance arts. ... 3D rendering of an ellipsoid In mathematics, an ellipsoid is a type of quadric that is a higher dimensional analogue of an ellipse. ... A reflector can mean one of several things: a reflecting telescope a device or a part of an antenna that reflects radio waves a device that causes reflection, for example, a mirror or a retroreflector a 1981 album by Pablo Cruise In LAPACK the term reflector with the types block... Prism splitting light Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of wavelengths that are studied in the field of optics. ... Lamp can be: A portable light fixture such as a table lamp or reading lamp (common usage) Lamp (electrical component), a replacable component that produces light, such as: Incandescent light bulb, also known as an incandescent lamp Fluorescent lamp Gas discharge lamp Arc lamp Signal lamp, a device used for... Barrel can refer to: Barrels for storage; especialy Barrels for aging alcoholic beverages. ... A lens. ... This article is about brands in marketing. ...

Characteristics of an ellipsoidal lighting unit include:

  • An adjustable barrel, allowing a lighting designer to change the size and focus of the light thrown by the unit by changing the distance between the mirror and the smooth, plano-convex lens or lenses
  • A set of brackets on the end of the barrel for the insertion of gel frames or a colour changer unit to alter the colour of the light
  • A series of shutters at the base of the barrel for shaping and narrowing the light beam
  • A slot in the body of the unit for the insertion of metal gobos to change the pattern of the light
  • A further slot for the addition of an iris to narrow the beam whilst keeping its circular nature.

The ERS improves over the efficiency of the fresnel lantern by surrounding the bulb in an ellipsoidal reflector, as opposed to the spherical reflector of the fresnel. This results in a much more controlable beam of light, which is typically shaped inside the instrument, through the use of shutters, as opposed to externally, using barn doors. A Color Gel, Color Filter, or simply Gel is a translucent or transparent coloured material that is used in theatre to colour light. ... Projected light shines through a Gobo and onto a screen for decorative, informational or dramatic effect. ... Fresnel A Fresnel lantern (or merely Fresnel) is a spotlight used in theatre, which employs a Fresnel lens to wash light over an area of the stage. ...

The biggest advantage of the ERS is its lower power consumption; the cost savings in electricity offset the higher initial cost of the instrument. 750 or 575 watt lamps are typically used, rather than the 1000 watt lamps common in older models. They generally provide better illumination and produce a cooler beam of light, due to the dichroic reflectors, employed on modern models, which reflects only the visible portions of the spectrum. Electric power is the amount of work done by an electric current in a unit time. ... The watt (symbol: W) is the SI derived unit of power. ...

The lamps are loaded from the rear, and either mounted axially, or vertically with the base either up or down (the orientation is important when mounting the instrument). The filament of the bulb is at one focus of the reflector and the aperture to the lens housing at the other. The shutters and gobo are ideally in focal point of this aperture. Axial has different meanings: In geometry it means: along the same line as an axis (coaxial) or centerline: parallel (geometry), contrary to radial or perpendicular In anatomy it relates to an anatomical direction of animals and humans. ... Filaments surrounding a solar flare, caused by the interaction of the plasma in the Suns atmopshere with its magnetic field. ...

Ellipsoidals are supplied with a certain size lens that determines the beam angle, normally five to fifty degrees. Variable focus instruments with two lenses are also available, allowing the user to manually adjust to the desired focal length. The focal point F and focal length f of a positive lens, a negative lens, a concave mirror, and a convex mirror. ...

The most popular type of ellipsoidal light in modern theaters is the Electronic Theatre Controls Source Four, which has a variety of special features including a rotating barrel, a slot to fit glass gobos, and a dichroic reflector. Other modern designs include the Lekolite and Altman Shakespeare series. Electronic Theatre Controls (ETC) is a theatrical lighting, dimming, and control company based in Middleton, Wisconsin. ... Halogen light bulb capsule (center) with an integrated dichroic reflector. ... A type of ERS (Elipsoidal Reflector Spot) designed by Strand Lighting, and widely used in theatre and entertainment venue environments during the 80s and 90s. ...

See also

Classical Spectacular used ordinary stage lighting plus special laser effects In the 2005 Classical Spectacular performance, a state of the art lighting system designed by Durham Marenghi was used to accompany the music Starry lighting such as is shown on the RHS of this photo are much more interesting than... This article is about lighting design in theater. ...

External links

  Results from FactBites:
Index ellipsoid - Wikipedia, the free encyclopedia (188 words)
The index ellipsoid is a diagram of an ellipsoid that depicts the orientation and relative magnitude of refractive indices in a crystal.
The equation for the ellipsoid is constructed using the electric displacement vector, D, and the dielectric constants.
The semiaxes of this ellipsoid are dielectric constants of the crystal.
ellipsoid - definition of ellipsoid in Encyclopedia (318 words)
In mathematics, an ellipsoid is a type of quadric that is a higher dimensional analogue of an ellipse.
If two of those numbers are equal, the ellipsoid is a spheroid; if all three are equal, we have a sphere.
The intersection of an ellipsoid with a plane is empty, a single point or an ellipse.
  More results at FactBites »



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