History There are many patents dating back from 1906 when Edmund Sohlberg of Kansas City. The lantern used a carbon-arc bulb and was operated not by motors or any form of electronics, but by cords that were operated manually to control pan, tilt and zoom.

1925 saw the first use of electrical motors being used to move the fixture, and with it the beam position, by Herbet F.King. Patent number: 1,680,685. In 1936 patent number 2,054,224 was granted to a similar device, but where the pan and tilt were controlled by means of joystick as opposed to switches. From this point on until 1969, various other inventors made similar lights and improved on the technology, but with no major breakthroughs.

During this period, Centuary Lighting (now Strand) started retailing such units specially made to order, retro fitted onto any of their existing lanterns up to 750 watts to control pan and tilt.

George Izenour made the next breakthrough in 1969 with the first ever fixture to use a mirror on the end of a ellipsoidal to redirect the beam of light remotely. In 1969 Jules Fisher, from Casa Manana area theatre in Texas saw the invention and use of 12 PAR 64 lanterns with 120watt, 12volts lamps fitted, 360 degrees of pan and 270 degrees of tilt, a standard that lasted util the 1990s. This lamp was also known as the ‘Mac-Spot’

In Bristol, 1968 progress was also being made, mainly for use in live music. Peter Wynne Wilson refers to the use of 1kw profiles, with slides onto which gobos printed, inserted from a reel just like on a slide projector. The fixtures also had an iris, a multiple coloured gel wheel. These lights were also fitted with mirrors and made for a impressive light show for a Pink Floyd Gig in London. Another fixture known as the ‘Cycklops’ was also used for music in the USA, although it was very limited in terms of capabilities with only pan and tilt functions and at 1.2meters long and weighing in at 97kg including the ballest, they were heavy and cumbersome.

In 1980 after the invention of Dichronic colour filters by Jim Bornhurst in early 1980 the dawn of the VariLite moving head became reality, starting with the VL0, demonstrated to Genisis in the summer. It also used one of the first lighting desks with a digital core and this enabled lighting states to be programed in. The demo to Genusis compromised of the VL0 hung in the centre of an old barn. Changing colour and moving from one corner of the room to another, the four executed steps were simple, but impressive to anyone who had not seen the technology before.

Genisis was later to order 55 VLO1′s to use in their next chain of gigs across the UK. The lights were supplied with a VL series 100 console which had 32 channels , five 1802 processors and a dramatic improvement of the first console which was very simple, had an external processing unit. The VL1 also demonstrated the first ever use of a XLR cable in a lighting-control application, though DMX was never sent through it.

In 1985 the first ever moving head was produced by Summa Technologies to use the DMX protocoll, which at the time was rare and was among many other formatts including DIN8, AMX, D54 and the protocols other companies such as Tasco, VariLite, High End and Coemar were producing. It also looked recognisable, a fixture that wouldn’t look out of place in a theatre. The Summa HTI had a 150watt HTI bulb, 2 colour wheels, a Gobo wheel, a mechanical dimmer and zoom functions. For the time, they had packed more features into it than anybody else before.

In 1987 ClayPacky began producing the first recognisable scanner, the Golden Scan. It utilised stepper motors instead of servos and used a HMI 575 lamp, bright and with a far more uniform beam brightness. Tbis was followed by the Intellabeam in 1989, also realsed by High End, who, at the time were the Distributors for Clay Paky and Belliveau.

In the 1990s the future came closer with Martin, a Danish Company producing Fog Machines. They manufactured a line of scanners known as the Roboscans, with a variety of different specs for different users. Their range started with the 218, for the small venue and went up in brightness and features through 518, 812, 918 and 1200Pro units. Martin also invented a whole new range of Moving Heads including the Mac250, the Mac250+, Mac300, Mac500, Mac600, Mac700, Mac1200 and more recently the Mac2000 and MacIII. Martin Mac’s are popular in most rental situations and are also a great compromise between the cheaper manufactured products and the top end luminaires such as a High End DL2.

The future promises many great things as the concept of digital lighting, a bright LCD or DLP projector mounted in a yoke or moving head type fixture with an integrated media server will allow for millions of colour choices, endless libraries of gobos, image and video projections to take place. The DL1 and DL2 by High End Systems (Barco) and Publitec Beamover.

Features

Several intelligent lights in use at a concert. Note the white beams they produce

An automated light, properly called a luminaire, fixture (or sometimes moving head), is a versatile and multi-function instrument designed to replace multiple conventional, non-moving lights. Depending on the venue and application, automated luminaires can be a versatile and economical addition to a stock of traditional lights because, with proper programming, they can swiftly alter many aspects of their optics, changing the ersonality of the light very quickly. Lighting is typically pre-programmed and played back using only simple commands, although moving heads can be controlled ive if the operator is sufficiently experienced.

Most moving heads have all or some of the features, each feature is set to a channel number, such as this:

Pan

Tilt

Fine Pan

Fine Tilt

Dimmer

Shutter

Gobo1 Select

Gobo1 Rotation

Gobo2 Select

Gobo2 Rotation

Gobo3 Select

Colour1

Cyan

Magenta

Yellow

Prism 3,5,9facet

Prism Rotation

Effects Wheel

Gobo Animation Wheel

Iris

Lamp Shut off, fixture reset

Remote patching channel

Control

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Moving lights are controlled in many ways. Usually the fixtures are connected to a Lighting control console, which outputs a control signal. This control signal sends data to the fixture usually in one of three ways: Analogue (which has largely been phased out), DMX (which is the industry standard control protocol), or Ethernet Control (which is still in development). The fixture then takes this signal and translates it into internal signals which are sent to the many stepper motors located inside.

XLR connectors, the most common method of controlling moving heads. Note that these are 3-pin XLR connectors, which are used by some manufacturers, rather than the 5-pin, which specified by the USITT DMX-512 Standard.

The vast majority of moving heads are controlled using the DMX protocol, usually using dedicated twisted pair, shielded cable with 5-pin XLR connectors at the ends. Each fixture is assigned a block of DMX channels in one of the venue’s DMX universes (a self-contained set of cables and fixtures which can operate a maximum of 512 individual channels). The central lighting desk transmits data on these channels which the intelligent fixture interprets as value settings for each of its many variables, including color, pattern, focus, prism, pan (horizontal swing), tilt (vertical swing), rotation speed, and animation.

Since moving heads did not attain prominence until DMX’s predecessor, analogue, had passed the zenith of its popularity, very few moving heads use analogue control (this is also due to crippling restrictions on bandwidth, data transfer speeds and potential inaccuracy). Some of the most modern intelligent fixtures use RJ-45 or Ethernet cabling for data transfer, due to the increased bandwidth available to control increasingly complicated effects. Using the new Ethernet technology, control surfaces are now able to control a much larger array of automated fixtures. Because many devices can be connected to a single RJ-45 network, these devices have the ability to not only listen to a control signal from a lighting control board, but have the ability to transmit information back to the control board and other entities on the network. Now, it is possible for a fixture to self-diagnose any problems, announce itself on a network, or accept setting changes from any place on the network, making obsolete older versions of the system that only had one central brain, the lighting control board. Because RJ-45 (and equivalent technologies) use bidirectional digital communication, bit-checking abilities allow for lighting control networks to safely operate devices that can interfere with human saftey (pyrotechnic devices, rigging mechanisms, etc.).

Moving lights are programmed using a fixture box in ETC light boards

Moving lights are much more difficult to program than their analogue cousins because they have more attributes per fixture that must be controlled. A simple conventional lighting fixture uses only one channel of control per unit: intensity. Everything else that the light must do is preset by human hands (color, position, focus, etc.) An automated lighting fixture can have as many as 30 of these control channels. A slew of products are available on the market to allow operators and programmers to easily control all of these channels on multiple fixtures. Lighting boards

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