By : Sachin chiplunkar, Production Engineer Gulf advance lighting
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THE 20TH CENTURY - (1900's)Although the principals of lighting design had been well established during the oil and gas light eras, it wasn't until the development of the incandescent lamp (c1879), that stage lighting could really flourish as an art form. Now for the first time in history it was possible to provide odorless and controlled lighting. The development of lighting fixtures flourished. The gas; striplight, box flood and footlights were redeveloped using the incandescent lamps.
BOX FLOOD / SCOOP / FLOODLIGHT - (1900's)The 'Box Flood' is an early type of basic stage lighting fixture. Before the widespread use of electricity and the incandescent lamp, candles, oil lamps and gas were all used for stage lighting. Long ago, some brilliant designer enclosed a typical flame source with a cube type housing, having only one open side. Voila, a significant development in lighting fixture design. First, the enclosure would have shielded the source from the audience, increasing visibility and visual comfort. Second, the enclosure would have acted as a crude reflector, helping to direct additional reflected light out of the front opening (or aperture).
Soon after the development of the incandescent lamp, the gas floodlight fixture would have been redesigned to incorporate this new technology. The electric box flood was the most basic of all stage lighting fixtures, as all that was required was a metal box, a socket, a power cord and a lamp. No lens or mechanical controls were required.
The illustration above shows a modern day floodlight fixture, using an electric filament lamp. This fixture, known as the 'Scoop', evolved from the simple box flood and provides a soft wide wash of light. Today modern fixtures often incorporate special asymmetrical reflectors, to help provide an even distribution of light on a vertical surface (backdrop or cyclorama). Some floodlights are also available in multi-cell designs, incorporating 2, 3 or 4 partitioned lamps, each with a different color filter. Modern floodlights typically come in wattages of 300 - 1000 watts.
LINNEBACH PROJECTOR - (c 1900)Adolf Linnebach was the technical director of the Munich Opera in the early 1900's. He developed a simple projector for background and scenic projection. The projector did not use a lens. Instead, it simply cast a shadow of a silhouette cutout, placed in front of the shielded, light source. The results was a simple, effective image projection, with a soft focus. (Bentham).
The modern Linnebach projector uses a slide size of 24x24 or 36x48 (inches). KLIEGL BROTHERS lighting, claims to have introduced the Linneback projector to the American market in 1922.
FOOTCANDLE (and LUX) - (a 1900)It was in the early days of electric lighting that users began to ask how much light they needed. The measurement unit of the footcandle was developed as a measure of 'illumination'.
DEFINITION - footcandle, fc: The unit of illuminance when the foot is taken as the unit of length. It is the illumination on a surface, one square foot in area on which there is a uniformity distributed flux of one lumen, or the illumination produced on a surface all points of which are at a distance of one foot from a directionally uniform point source of one [CANDELA]. (REF: IES Lighting Handbook, Ref. Vol. 1981).
The International (metric) unit of illumination is the 'lux'. It is the illumination produced on a surface one square meter in area at a distance of one meter from a uniform point source.
Lux / Footcandle conversions:
FC = LUX x .0929 - Example 1: 500 LUX x .0929 = 46.5 FC
LUX = FC x 10.76 - Example 2: 50 FC x 10.76 = 538 LUX
Generally you may multiple FC by 10 to obtain LUX - or, divide LUX by 10 to obtain FC.
The recommended illuminance levels for various activities and tasks are published by the Illuminating Engineering Society. Today we know that it is not just the 'amount' of light that affects visibility. Other factors such as contrast and glare are equally important.
The illumination from the sun on the earth's surface can exceed 100,000 LUX, (or 10,000 FC) during a summer day. At night the reflected light from the moon might be as high as 0.2 LUX, (or .002 FC).
SALTWATER DIMMER - (a 1900)Soon after the development of the electric filament lamp, applications were immediately found in the theatre for this exciting new invention. New lighting fixtures and methods of control were quickly developed and put into use. One early means of lamp 'dimming' was through the use of the salt water dimmer. The dimmer consisted of a tank (or barrel) of salt water brine with a permanent electrode submerged. As a second electrode was slowly raised (or lowered) into the brine, the conductivity between the two electrodes would increase (or decrease) respectively. Lamps connected in series to the dimmer, would be dimmed accordingly. It was not uncommon for a theatre to have a large number of these dimmers and it is said that the heat from the boiling brine would often help to heat the backstage areas. Undoubtedly messy and difficult to operate and maintain, the electric salt water dimmer was soon to be replaced by the somewhat more efficient (and dryer) electrical resistance dimmer.
See also: RESISTANCE DIMMER, AUTOTRANSFORMER DIMMER, SCR DIMMER.
MCCANDLESS, STANLEY - (c 1900 - 1967)Stanley McCandless (American) is often regarded as the 'father' of modern stage lighting design. He worked as a teacher, educator and lighting designer, throughout his career. After graduating from the University of Wisconsin, "Mac" got his degree in architecture at Harvard. He then worked as an architect for some time and in the late 1920's he opened an office in New York City as an independent lighting consultant. He was the architectural lighting consultant for Radio City Music Hall and many other important projects. With the opening of the Yale School or Drama in the 1920's he was asked to teach stage lighting. He taught at Yale between 1925 and his retirement in 1964.
McCandless wrote two very important books on stage lighting "A method of lighting the Stage" (1st published, 1928), and "A Syllabus of Stage Lighting". McCandless provided a 'method' of lighting that is still the foundation of modern lighting methods today. He taught visibility of the actor first, and illumination of the surrounding scenery, second. He proposed a system of dividing a typical (proscenium) stage in to 'acting areas'. Each area was lighted with two fixtures - placed at 90 degrees to each other, and in a 45 degree frontal position to the actor. For additional interest, McCandless recommended a 'warm' color from one side and a 'cool' color from the other.
McCandless was also the holder of numerous patents in the architectural lighting field. He consulted on some of the largest and most important projects at the time in the American nation. He taught many lighting professionals in the field and lectured and wrote extensively in architectural and illumination publications.
RAMBUSH, HAROLD W. - (c 1900 - 1981)Harold Rambush was the interior designer of many American and Canadian cathedrals and church interiors, (over 500) as well as the decorator of numerous American theatres, including the Roxy and Radio City Music Hall. He also served as the director of the Rambusch Company, a leading American manufacturer of church lighting fixtures, founded by his father in 1898.
MIELZINER, JO - (1901 - 1976)Jo Mielziner designed sets and lighting for more than 300 productions. He designed his first Broadway play in 1924 and was active in the theatre until his death in 1976. Among his most famous Broadway productions were "Carousel", "Annie Get Your Gun", "A Streetcar Named Desire", "Death of a Salesman", "The King and I", "South Pacific", "Look Homeward Angel" and "Gypsy". (BW)
Additional Reading: Theatre Design & Technology, May 1969
HIGH INTENSITY DISCHARGE (HID) LAMP - (1901)High Intensity Discharge (HID) lamps and lighting have been in use since the early days of the 20th Century, as an alternative to the electric filament lamp. The first HID lamp introduced was the mercury lamp in 1901. Later, low pressure sodium, high pressure sodium and metal halide lamps, were developed. All of these sources consist of electric arcs, operating in a gaseous environment, sealed within a glass tube or bulb. HID light sources are all more efficient than the electric filament lamp, however they also have limited color rendering abilities, due to their 'line' spectrum (not continuous spectrum). Many HID lamps are now also provided with a phosphor coating on the inside of the bulb. This coating causes additional secondary emissions of visual radiation, providing a wider 'spectrum' of light and color. Typical applications include industrial, commercial and architectural lighting.
See also: [METAL HALIDE LAMP], [MERCURY-VAPOR LAMP], [SODIUM LAMP]
MERCURY-VAPOR LAMP - (1901)The first practical mercury-vapor lamp was the Cooper-Hewitt lamp developed by Peter Cooper Hewitt in 1901. This was a tubular source about 4 feet long which produced light that was distinctly bluish green in color. The first high pressure mercury lamps similar to the ones used today, were introduced in 1934 in the 400 watt size. Today, mercury lamps now available, range in size from 40 watts to 1000 watts. Mercury lamps produce approximately 55-60 lumens per watt.
Operation: the arc tube of the mercury lamp has argon gas and a little pearl of mercury as filling ingredients. It's electrodes are made of tungsten and carry an emitter paste, e.g. a barium-yttrium compound, that reduces the ignition voltage required to start the lamp. Within three to five minutes after ignition, the mercury is completely vaporized and the characteristic blue-green spectrum of the mercury discharge is emitted. It contains strong ultraviolet radiation at wavelengths of 254 nm and 365 nm. Radiation in the red area of the spectrum is virtually negligible. A mercury lamp's color temperature ranges between 4000K and 4500K, while its color rendering index (CRI) is only approximately 20, for a clear bulb. Applying phosphor coatings to the outer bulb increases the light output by 10 to 15 percent and improves the CRI to approximately 50.
ALBERT EINSTEIN - 1905THE SPEED OF LIGHT - In 1905 Einstein postulated that nothing in the universe travels faster than the speed of light and he put forward his Special Theory of Relatively. Although many scientists have tried to test his theory, none have proven him wrong. In the vacuum of space, light travels at approximately 186,000 miles per second. This gave rise to a special T-shirt design worn at such places as MIT and Caltec:
IT'S NOT JUST A GOOD IDEA
IT'S THE LAW!
LIGHTYEARThe lightyear is an astronomical measurement used to measure distance, not time. There are approximately 31.5 million seconds in a year. This means that light can travel a distance of 5.60 trillion miles in one year. The metric light year is approximately 9.5 trillion kilometers. The Milky Way is approximately 100,000 lightyears in diameter.
ILLUMINATING ENGINEERING SOCIETY - (1906)I.E.S. (IESNA/IES) - The Illuminating Engineering Society of North America. The I.E.S. was formed in 1906 and has approximately 10,000 members world wide. Its membership includes; lighting consultants, engineers, architects, users, educators, equipment sellers and others, dedicated to the areas of lighting and illumination. Through its activities in research in all phases of lighting application, it has achieved recognition as the authority for recommended illumination practices in North America. The I.E.S. also makes available a great many lighting related publications. The society is located at 345 East 47 Street, New York, NW, 10017 (212) 705-7926.
Honorary IES membership was presented to Thomas Alva Edison on February 10, 1916 at the Hotel Biltmore in New York City.
INVENTION OF THE VACUUM TUBE - (1906)In 1906, the American engineer, Lee De Forest, patented the triode vacuum tube. By 1920 the tube had been improve to the point where it could be used to amplify electric currents for television.
TUNGSTEN FILAMENT LAMP - (1907)Prior to 1880 all filaments were either carbonized paper or cotton thread. From 1880 to 1894 bamboo was the usual filament material. In the 1888-1890 period, the squirted cellulose filament appeared. The tantalum lamp was introduced in 1908 and the first tungsten filament lamps were used about 1907-1910.
The first electric lamps using tungsten filaments first appeared in America in 1907, and were made in wattages up to 500 watts. The filaments were extremely fragile however.
The ductile tungsten filament was developed about 1911 by William D. Coolidge, (General Electric, Research Laboratory). This resulted in a much more durable and rugged lamp design. Tungsten has a melting point of 3370 degrees C. (Visible light is produced when a filament reaches 572 degrees Fahrenheit - 'DuroTest').
Additional Reading: LDA, July, 1980, file
ROSCO LABORATORIES - (1910)Rosco manufacturers and supplies a wide range of products for the entertainment industry and has offices in New York, Hollywood, Toronto, London, Madrid and Sydney. Products include 'Roscolux' brand lighting filters, stainless steel projection templates (gobos), scenic paints, fabrics, plastics, projections screens, flooring, software and many other unique items.
"In 1915, the Rosco swatchbook had three blues: Medium Blue, Dark Blue and Green Blue. By the 1930's the range had expanded to six blues, including Daylight Blue, Pale Blue and No Color Blue". Rosco began producing color in 1910. (REF: quote, Rosco advertisements, Theatre Crafts, Feb/1989, pg 4).
See also: [ROSCOLUX].
Rosco Laboratories 30 Bush Avenue
Port Chester, NY, 10573, USA
Fax: 914-937-5984 (New York)
800-ROSCONY (New York)
RESISTANCE DIMMER - (a 1910)One of the earliest electrical dimmers put to use in the theatre (after the [SALTWATER DIMMER]) was the 'resistance dimmer'. The resistance dimmer was simply a long length of wire, usually wound in the form of a coil. A 'wiper' contact would move along the coil, usually controlled by a manual leaver (or motor control). As the contact moved along the coil, the coil resistance would decreasing or increase accordingly. This coil resistance was placed in series with one or more electrical filament lamps to provide a relatively efficient means of dimming.
Stage lighting switchboards were large and heavy. Many used an elaborate system of sub-switches and interlocking control levers. Master leavers were often provided to allow a single operator to raise or lower the control handles of a number of dimmers, all at the same time. It usually required considerable skill to achieve a smooth fade.
KELLY, RICHARD - (1910 - 1977)Richard Kelly was an American, architectural lightning designer and consultant, with a vast number of projects credits. He also did extensive work with day lighting. He was familiar with the destructive characteristics of light (UV) and provided the lighting for a number of leading art galleries and museums.
BAY, HOWARD - (1912 - 1986)Howard Bay has designed the sets and lighting for over 170 Broadway shows. He had designed fifty-seven Broadway productions by the time he was thirty-six. Among his credits are "Man of La Mancha", "Music Man", and "Show Boat". His Broadway career began in 1933 with 'There's a Moon Tonight'. His first designs for a musical were for 'Count Me In'.) His book, "Stage Design" is one of the most popular textbooks of its type.
Additional reading: Theatre Design and Technology, December 1969.
ROSENTHAL, JEAN - (1912 - 1968)Jean Rosenthal born, N.Y.C. Studied at Yale with Stanley McCandless (c. 1932), and later went on to become one of the leading lighting designers on Broadway and in modern theatre. She was a pioneer in the art and craft of lighting design. Over her 30 year career, she is said to have designed over 400 productions, including plays, musicals, opera and ballet. Among her best known Broadway shows were "West Side Story", "Plaza Suite", "Becket", "Hello Dolly", "Hamlet" (with Richard Burton", "The Odd Couple", "Cabaret", "The Sound of Music" and "Fiddler on the Roof". Her well known book; "The Magic of Light", is published by Little, Brown and Company in association with Theater Arts Books.
COOLIDGE, WILLIAM DAVID - (1913)Coolidge was a General Electric research worker who in 1913 received a patent for "tungsten and method for making same for use as filaments of incandescent electric lamps". Tungsten will now replace carbon filaments in the manufacture of Edison and Swan lamps
GAS FILLED LAMP - (1913)Up to this time, all lamp filaments operated in a high vacuum. After the introduction of the tungsten filament, by [COOLIDGE] the next highly significant step in the development of the incandescent lamp, came in 1913 when [LANGMUIR] (G.E. Research Lab.) made the first gas-filled lamp, at atmospheric pressure. He found that the higher pressure did reduced evaporation of the tungsten, but so much heat was conducted away by the gas that the lamp efficiency was reduced. He discovered that coiling the filament reduced the effective area exposed to the gas and thus minimized the loss of heat. Coiled filament gas-filled lamps in 500, 750 and 1000 watt sizes were introduced in 1913. They gave a much better light at higher efficiency with the same life as former lamps. Nitrogen gas was used in the first lamps but argon was substituted in 1914. Argon has lower heat conductivity than nitrogen. These lamps could be made smaller than carbon lamps and produced three times the light per watt.
Now the development of advanced lighting fixtures and projectors, using lenses, was possible. See also: [IRVING LANGMUIR] (1881 - 1957).
HUB ELECTRIC COMPANY INC - (c 1915)Hub was a large American manufacturer of theatre lighting products, located in Illinois. The company was active in educational theatre and provided a wide range of dimming products and design services.
MAJOR CONTROLS - (1916)'Major' was formed in 1916 and is one of the oldest manufacturers of theatre lighting systems.
740 Industrial Drive,
Cary, Illinois, 60013, USA
Tel: (312) 639-8200.
STRAND ELECTRIC COMPANY - (1917)
STRAND LIGHTINGThe Strand Electric Company was established in 1917 in London, to serve the needs of the London theatre district. Strand Lighting Canada began operations in 1958. In 1969 the Rank Organization acquired both Strand Lighting and the American company of Century Lighting and consolidated them as Strand Century. Rank combined all of its Strand Century Companies into one international group under the Strand Lighting name in August 1985. In 1986 Rank acquired Electro Controls (Controls Lighting) of Salt Lake City, Utah and Calgary and Quartzcolor Ianiro SPA of Rome. In the fall of 1996 Schroder Ventures purchased the Strand Lighting International Group of companies from Rank. Today 'Strand', with offices around the world, manufacturers one of the most comprehensive ranges of lighting fixtures, dimming and control equipment for theatre and television, in the industry.
See also: [CENTURY LIGHTING]
18111 South Santa Fe Avenue
Rancho Dominguea, CA, 90221, USA
See also: [CENTURY LIGHTING].
ADB LIGHTING - (1920)ADB is a large European lighting company currently based in Belgian. The company was founded by Adrien De Backer in 1920 and started as manufacturers of electrical equipment including rheostats.As eqrly as 1925 ADB had developed rheostats to control the lighting for stages, music halls and movie theatres. Today the company manufactures a wide range of luminaires, accessories, dimming and controls, for the theatre and television markets. ADB has been a 'Siemens' company since 1987.
STRIPLIGHT / COMPARTMENT BATTEN - (1920's)The striplight (compartment batten, in Britain) is a stage lighting fixture, designed to provide a linear 'wash' of light. In addition to being used for the lighting of scenery, striplights are also useful for the lighting of cycloramas and backdrops. Early striplights would have used candles, oil or gas and would have been most unpractical to handle and difficult to control.
In England, the compartment batten was made popular by Adrian Samoiloff who used many for his color lighting stunts, which hit the headlines in the early 1920's. Prior to the compartment batten, color was obtained by dipping the individual lamps in lacquer.
Today, the modern striplight is 6 to 10 feet in length and, wired in 3 or 4 circuits. Usually lamps of 100 - 500 watts are used behind plastic or glass filters. Sometimes the primary colors of light, red, green and blue are used. When the colors are 'mixed' together with dimmers, a wide range of dramatic colors may be attained. Often striplights will be used to illuminate large sky cloths. They are usually placed end to end, above the cloth, running from one side of the stage to the other. Additional striplights are often also placed on the floor, parallel to the cloth. The floor strips can provide an assortment of horizon lighting including sunrise and sunset effects.
FIRST - FRESNEL LENS SPOTLIGHT - (c 1920)The modern fresnel spotlight is one of the most basic tools used by lighting designers for spot-lighting applications. The fresnel spotlight, in its simplest form consists of a housing, a light source and a 'fresnel' lens. When the source is moved slightly towards (or away) from the lens, the size of the light beam changes, from spot focus to flood focus. Early fresnel type lighting fixtures would have included, gas, oil, electric arc and other sources, and were commonly used as lighthouse type fixtures, able to project a narrow concentrated beam, a great distance.
The modern fresnel lighting fixture uses either a tungsten halogen or a discharge type of lamp. Fresnel fixtures are available in lens diameters of 3 inches to 36 inches or more. The typical stage and studio fresnel has a lens diameter of 6, 8 or 10 inches.
Today, the fresnel with its adjustable beam size is invaluable for area lighting and color wash applications. The fresnel fixture produces a 'round' beam with an intense 'hot' center and a 'soft', yet defined edge. Fresnel fixtures come in wattages of 150 to 10,000 watts and have adjustable beam spreads of from 10 to 60 degrees.
The fresnel lens and the early fresnel fixture was developed by and named for, [AUGUSTIN JEAN FRESNEL], (1788 - 1827).
[KLIEGL BROTHERS] (in a 1969 catalog) claims the incorporation of a fresnel lens into a theatrical lighting fixture, in 1929.
LEVE, CHARLES - (1922 - 1985)Charles Leve was a graduate of Yale University Drama School and later went on to be the director of development of lighting, for Strand Century, a position he held for 34 years, since 1951. Leve was also the designer of the Light Palette, a computerized lighting control system that did much to revolutionize theatre lighting of Broadway shows. Prior to his death Leve also had worked with Colortran Inc. and Four Star Stage Lighting.
SCHWABE - (1923)Schwabe (Germany) was a leader in the development of early stage lighting fixtures (not dimmers and control). The firm of 'Reiche and Vogel' is a descendent of the Schwabe Company. Schwabe made a number of theatre lighting installations in London, as early as 1923. (St. Martin's Theatre).
REICHE AND VOGEL - (1923)- see: SCHWABE
NIETHAMMER, EMIL - (c 1924)Emil Niethammer, founded about 1924, is a large manufacturer of high quality stage and studio lighting fixtures. The company is located in Stuttgart, West Germany and was purchased by [AVAB] in the late 1980's. All fixtures are designed and manufactured to a very high standard, and optical performance is among the best in the world.
STROBOSCOPE (ELECTRONIC STROBE) - (c 1926)EARLY STROBOSCOPE
The stroboscope is a device for viewing a rotating object by making the object appear to be at rest. In its simplest form, it consists of a rotating disk with one or more viewing slits, through which the object can be viewed. The observer looks through the viewing slit and sees the object in exactly the same position each time the slit passes the observers eye. The disk must be rotated in precise synchronization with the object. If the disk is rotated slightly slower than the object, the object will appear to be moving slowly in the direction of its actual motion. If the disk is turning faster that the moving object, then the object will appear to move slowly in the direction opposite to its actual motion.
The stroboscope is of great use in engineering studies of moving parts, as they can actually 'freeze' and view the image in real time.
Modern stroboscopes no longer use the rotating wheel with slits. Instead electric lamps are utilized that produce short flashes of light at the same rate that the object is revolving. The high speed gas discharge lamp, stroboscope was developed by Harold Eugene Edgerton and his associates at the Massachusetts Institute of Technology around 1926 to 1931. Today, [NEON] lamps are also commonly used for low power stroboscopic applications, producing a flash rate synchronized with a 50/60 cycle frequency, of the standard A.C. (alternating current) power line.
On a darkened stage in a theatre, a single flashing light source can provide a very striking and dynamic - stop action effect, of all moving objects on stage.
During the mid-1900's, a device known as the 'lobsterscope' was developed for theatre and stage applications. The device consisted of a spinning disk with apertures to mechanically 'chop' the beam of light produced from an incandescent spotlight. This produced a rapid flickering light, able to 'freeze' the action on stage.
During the 1960's the [XENON] 'Strobe' was frequently used for discotheque lighting applications. Designers tried to build the 'ultimate' strobe and units continued to became larger, brighter and more sophisticated. Often several powerful strobe units would be used in a single stage production, with control systems developed to synchronize their firing from a number of inputs (audio beat, keyboard, programmer, etc.)
Today strobe technology in the entertainment industry is stronger than ever. Large productions might incorporate 50-100 or more units, usually mounted in banks of several fixtures each.
FIRST - PUBLIC TELEVISION - (1926)On January 27, 1926, the first public demonstration of television was given. The first commercial color TV broadcast was presented by CBS on June 25, 1951.
CENTURY LIGHTING - (1926)Century Lighting opened for business in New York in 1926. The company later was purchased by [STRAND ELECTRIC] to become 'Century Strand', then 'Strand Century' then finally [STRAND LIGHTING], in the 1990's. 'Century Lighting' (USA) made many fine lighting products, including fixtures, dimmers and accessories for stage and television lighting. Century also produced the well known 'leko', (ellipsoidal reflector spotlight), in a number of different sizes and wattages.
The company was founded by Ed Kook and Joseph [LEVE].
MOLE-RICHARDSON CO. - (c 1927)Established about 1927, Mole Richardson is one of the leading manufacturers in the world of motion picture, television and professional photographic lighting. They manufacturer an extensive range of lighting fixtures and related accessories and are located in Hollywood California, USA.
937 North Sycamore Avenue
Hollywood CA, 90038-2384, USA
Tel: (213) 851-0111
Fax: (213) 851-5593
SKELTON, THOMAS R. - (1928 - 1994)Tom Skelton, was an well known American stage lighting designer. He died, August 10, 1991. at the age of 66. "The late Tom Skelton was an artist truly revered in the entertainment industry. He began his lighting career as an apprentice to Jean Rosenthal. He went on to inspire other great designers including Jennifer Tipton and Paul Gallo. Skelton was a brilliant lighting designer and innovated color techniques for both theatre and dance. He designed for the Jeffrey, New York City, Paul Taylor, Jose Limon and the Ohio Ballet, which he co-founded. His Broadway credits include "A Few Good Men", "Peter Pan", "Oklahoma", "Brigadoon", "The King and I", "Carousel", and the revivals of "The Iceman Cometh", and "Death of a Salesman". He received 3 Tony nominations, the Carbonelle Award. and the Los Angeles Drama Critics' Award during his career." (REF: quote from, Rosco, Pattern Catalog, 1996).
CLEMANCON - (1928)The French firm of Clemoncon, was founded in Paris in 1928, and has a long record in the manufacturing of stage lighting equipment.
UNION CONNECTOR CO., INC. - (1929)In 1929, the Union Connector Company was founded by William J. Wolpert, as a manufacturer of stage lighting connectors. Today, the company makes a large variety of high quality electrical connectors for the stage, motion picture and television industries.
Union Connector Co., Inc.
300 Babylon Turnpike
Roosevelt, New York, 11575, USA
Tel: (616) 623-7461
Fax: (616) 623-7475
PANI, LUDWIG - (1930)The Viennese firm of Ludwig Pani, is one of the world's leading manufacturers of projection and lighting equipment. The firm was formed in 1930 as a division of the optics firm: 'Optischen Werke C. Reichert, Wien'. Herr Pani who headed the projection division of the parent company, gave his name to the new firm. Pani manufacturer a number of different high powered, optical projectors, accessories and lenses. Pani has several models including a 2000 and 5000 watt incandescent model and a super bright 4000 watt HMI model. These projectors are suitable for large scale scenic projection, for opera and other large scale projections including outdoor architectural and building projection, at night. Pani projectors are very expensive, but very impressive. In the USA, the firm is represented by Production Arts, (New York City, USA).
FLASHBULB - (1930)The photographic flashbulb was patented by a German inventor, Johannes Ostermeir. A small filament in the 'flash lamp' heated to ignite foil inside the bulb, providing a bright, smokeless, flash of light. This provided a much safer and more practical means of photographic illumination than did previous methods using flash powder.
TIMES SQUARE CORP. - (a 1930)TIMES SQUARE THEATRICAL AND STUDIO SUPPLY CORP. was established around 1930 in New York City. Since its inception, the company has grown to be a leading supplier lighting equipment and accessories to the stage, studio and entertainment industries, around the world.
Times Square Lighting,
Industrial Park, Route 9W.
Stony Point, N.Y., 10980, USA,
Tel: (914) 947-3034,
Fax: (914) 947-3037
COMMISSION INTERNATIONAL DE L'ECLAIRAGE, (CIE) - (1931)C.I.E. (CIE) - The International Commission on Illumination, in 1931, adapted a set of tables to define the color matching characteristics or a standard observer and establish a framework for the specification of colors. This was the trichromatic system of color measurement. The recommendations were for pure spectrum colors and were based on a number of research programs which dated from at least as early as MAXWELL'S work in 1854, and continued by other researchers until 1931.
Additional reading: Measurement of Color, W.D. Write, 1964, Hilger & Watts Ltd., London.
LAND, EDWIN HERBERT- See: [POLAROID FILTER], [POLAROID CAMERA]
POLAROID FILTER - (1932)The principals of polarized light have been known for many years, having been discovered by [HUYGENS] in 1678. It was the American inventor Edwin Herbert Land however who in 1932 invented a material to conveniently produce polarized light from ordinary light. The light gray glass or plastic filters are relatively inexpensive, and only pass light waves vibrating in one direction. The filter material is now known by the trademark 'Polaroid'.
Today, there are several modern uses of polarized light. Glare from the sun (or other source) reflecting off of a shiny surface will often reflect polarized light. If the glare is viewed through a polarization filter, the glare will disappear and reappear, as the filter is slowly rotated around a central axis. This is the exact principal used in polarized sunglasses. The orientation of the filter tends to block any reflected polarized glare, that is not on axis with the filter. 'Polaroid' sunglasses were introduced by Land-Wheelwright Laboratories in 1936. The following year the company changed its name to the Polaroid Corp.
Polarized light also has several spectacular visual properties associated with it. For example many crystals and plastics produce impressive and dramatic colors when illuminated with and viewed under polarized light. This principal is used in the study of stress in engineering structures. A scale model (of a bridge for example) will be constructed from clear plastic. The model will be illuminated with polarized light and viewed through a polarized filter. Any loads or stresses placed on the scale model will immediately produce dynamic color effects, showing stress lines throughout the structure. The crumpled plastic from a cigarette package and two small polarized filters can demonstrate this colorful experience.
In the 1960's and early 1970's many 'light shows' made and projected slides, made from crumpled and scrunched pieces of clear plastic sandwiched with a polarized filter. When projected from a source with a polarized filter on the lens, the image would become alive with color. When the filter at the lens was rotated the images would swirl, flicker and dance in a psychedelic display of color.
See also : [POLARIZATION/POLARIZED LIGHT]
SODIUM LAMP - (LOW PRESSURE) - (1932)L.P.S. (LPS) - Research into low pressure sodium gas discharge lamps started in the 1920's. The first commercial application was a road lighting installation that was put into service between Beek and Geleen in the south of the Netherlands on July 1, 1932. The installation employed low pressure sodium lamps with a lumen efficacy 40 lumens per watt. In the same year, the Purley Way in London was also lit by low pressure sodium lamps. Today, the modern low pressure sodium lamp, is considered to be the most efficient lamp available, providing more than 220 lumens per watt. Low pressure sodium lamps can be recognized from their deep amber color.
Additional Reading: LDA, June 1983, Low pressure sodium lighting, the past, present and future - (file)
See also: SODIUM LAMP - (HIGH PRESSURE)
ELLIPSOIDAL REFLECTOR SPOTLIGHT - (1933)Although not completely certain, the invention of the modern ellipsoidal reflector spotlight often goes to [KLIEGL BROTHERS] (USA). In 1933, the first KLIEGLIGHT, was used in the spectacular outdoor pageant "Romance of the People", at the Polo Grounds in New York. Its first indoor use was in the Earl Carrol Vanities of the same year. Century Lighting (USA) produced a similar fixture in the same year known as the [LEKOLITE].
Today, the ellipsoidal reflector spotlight is still one of the basic tools of the stage lighting designer for spot-lighting applications. The 'ER' as it is often known, is also used to a lesser extent in modern television and film lighting applications. In Britain the 'ER' is referred to as a 'profile spotlight' or a 'mirror spot'.
In its simplest form, the ER fixture consists of a housing, a light source, an ellipsoidal reflector and a plano convex lens. The light beam produced by an ER fixture is round (or 'conical') with a sharp defined cut-off edge. The fixture is actually a simple projection device and will optically project the image of anything placed at its focal point. The typical ER fixture has 4 integral framing shutters or an iris - to provided limited beam shaping. In addition, and of particular importance the ER fixture will also accept and project the design of a metal pattern, commonly known as a template or gobo. There are hundreds of different stock patterns and designs available from various manufacturers.
The typical ER spotlight uses a tungsten halogen type of lamp. Fixtures are available in lens diameters from about 4" to 10" and with wattages from 500 to 2000 watts. The typical stage and studio ER fixture has a lens diameter of 6 inches and a 1000 Watt lamp.
The ER spotlight is selected by beam spread. Fixed beam spreads are available as follows: 5, 10, 15, 20, 25, 30, 35, 40, 50 degrees. Formerly in North America (1950's-1980's) beam spread was designated by specifying first the diameter and then the focal length of the lens. Example: a 6x9 (pronounced 6 by 9) was a fixture with a 6" diameter lens and a 9" focal length. In order to determine the spread in degrees of any particular fixture, the designer still needed to consult the manufacturers data sheet as the designation did not accurately identify the beam spread of the fixture. Today spotlights are specified in 'degrees' only. The following table shows approximate beam spread of several common ER spotlight fixtures:
- 6x9 - 40 degrees
- 6x12 - 30 degrees
- 6x16 - 25 degrees
- 6x22 - 15 degrees
- 8x9 - 20 degrees
- 8x13 - 13 degrees
- 10x20 - 15 degrees
'LEKO' (also LEKOLITE) - (1933)About the same time that [KLIEGL BROTHERS] developed the first ellipsoidal reflector spotlight, [CENTURY LIGHTING] also developed a similar type of lighting fixture known as the [LEKO] or [LEKOLIGHT].
Joseph [LEVE] and Edward F. Kook were founders of Century Lighting and in 1933 they filed a patent for a new type of reflector spotlight. Each gave one half of their names LE and KO to their joint development. The 'leko' used an ellipsoidal reflector with beam shaping controls (shutters & templates). The leko is still manufactured today by [STRAND LIGHTING], however it has gone through many improvements over the years. Although the term 'Lekolite' is often used to generically refer to any type of ellipsoidal reflector, lighting fixture, the name is now owned by Strand and Strand alone, has the right to use the name.
See also: [ELLIPSOIDAL REFLECTOR SPOTLIGHT]
GOBO/TEMPLATE - (a 1933)The development of the modern [ELLIPSOIDAL REFLECTOR SPOTLIGHT] (1933), provided an effective acting area type of fixture. It also provided, however, a 'crude' but effective method of image projection.
Typically a pattern is cut or etched into a thin metal plate. When the plate is inserted into a slot, at the focal point of the fixture, an image of the pattern is projected. As the pattern or template was 'to go between' the lamp and the lens - it is was nicknamed: 'gobo'.
The use of template projection is a very valuable tool for the modern lighting designer. Many designers use gobos to provide 'texture' to acting area lighting. Other designers use gobos to provide interesting floor patterns, or to texture the scenery. The image may often be slightly softened, by placing the lens out of focus. Alternately a sharp image may be produced, by 'hard' focusing the lens. Focus may sometimes be made even sharper by the addition of a 'donut' in the color frame. Typically a donut for a 6" ellipsoidal reflector spotlight consists of a 7.5" x 7.5" foil mask, with a 2-3 inch hole, punched in the center. Although the image will be sharpened, by the use of the donut, some intensity, will also be lost.
Several companies produce 'stock' pattern designs precision etched in stainless steel. Both the [GREAT AMERICAN MARKET] and [ROSCO] produce hundreds of unique designs in several different sizes. It is also possible to custom etch your own projection templates using brass shim stock and an etchent of potassium ferra-chloride.
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Thx...good information! Waiting for rest 50 Sachin