Vari-Lite

VARI*LITE is the brand name of one of the first automated, variable-colour stage lighting systems to be created. Their intelligent lighting fixtures are commonly used in theatre, concerts, television, film and corporate events.

History

Pre-history

The origins of Vari-Lite date to the late 1960s,[1] when college friends Jack Calmes and Rusty Brutsché[2] played together in a Texas-based blues band. They built a sound system for their shows which was of such quality, that other acts asked to rent it from them.

In March 1970 Calmes and Brutsché, together with sound engineer Jack Maxson, incorporated Showco, with the intention of hiring sound systems to regional rock concerts. The company initially operated two sound systems and two trucks from Maxson's garage.

The company quickly grew, both in size and reputation, and added lighting equipment to its inventory in 1972.

By the end of the 1970s, with the competition growing, the company began looking for new ways to compete. In particular, Showco's lighting equipment was fast becoming outdated and the company could not afford to replace it.

Invention and after

Showco had a very active R&D department, continuously looking for new technology. At the time, many companies within this market were trying to solve the problem of a producing reliable and robust colour change unit for lighting fixtures. Many of these took the form of wheels, semaphore-type devices or scrolls of Gel. However, coloured gel had a tendency to burn or rip if used incorrectly.

In 1980, one of the company engineers, Jim Bornhorst,[3][4] while looking at alternative methods of colouring light, realised that dichroic filters display a strange side effect: when you twist them, the frequency of light on which the filter operates, shifts—causing it to apparently change colour. That might have been the extent of their advancement if not for a barbecue lunch in the fall of 1980. At that gathering, the idea of adding two extra motors to the fixture to actually make the light move was conceived. This "eureka" moment facilitated an all-out building effort for a fully automated lighting system. This idea, coupled with the recent appearance on the market of the General Electric Marc 350 projector lamp resulted in a prototype in December 1980, that had taken twelve weeks to build.[5]

Also in 1980, Jack Calmes resigned as president of Showco and went on to found Syncrolite[6] in 1984.

At the time, Showco were regular suppliers to the British band Genesis, who were always looking for new ideas for their stage shows. A number of Showco staff, including Rusty Brutsché and Jim Bornhorst, flew over to see the band and their manager in England, to show them the prototype—today known as the VL-Zero. The prototype was so simple it was built on a wooden baseplate and had no hanging method, so the team had to nail it to a beam in the outbuilding that was being used for the demonstration at an English countryside studio. The new luminaire made its debut on the side of a 500-year-old barn, and the prototype light had been programmed to enact two simple cues. The first reaction from the presentation came from band member Mike Rutherford: "I expected the colour change, but by Jove, I didn't know it was going to move."

It was enough to convince Genesis to immediately invest in developing this new technology. Having gone over there with the idea of getting some advance rental fees for the next Genesis tour, the band's manager, Tony Smith instead offered to invest in the new idea, and when the team headed back to the airport, they had a cheque for $1M in their pockets. On the plane home Jim Bornhorst dropped the bombshell: The twisting dichroic technology was not ready—they were going to have to design a new luminaire from scratch, in time for the band's next tour. This luminaire became known as the VL1.

Work began right away, not just on the new luminaire, but on the development of a whole lighting system—complete with a control console, power distribution and digital data transmission. Several patents were filed, in order to protect this brand new technology and the intellectual property associated with it—including US Patent No. 4392187,[7] which described the basic system and covered both the twisting dichroic method of colour-changing and the alternative, wheel-based method, that would eventually be used in the VL1.

By the time the Abacab tour started in Barcelona, on September 25, 1981, not only were there 50 active VL1's, plus spares, but also a brand new multi-processor control desk, with software written by Brooks Taylor. The electric and electronic hardware were designed by John Covington & Tom Walsh. The console operator for this tour was a young man by the name of Tom Littrell, who had been taken on for the summer during the college break, and never looked back.

By this point a new company had been incorporated, with a name coined from a suggestion by Genesis manager Tony Smith. The company was called Vari-Lite Inc. By 1984 the product name was actively being differentiated from the company by using an asterisk (VARI*LITE). The asterisk went on to become the basis of the company logo, in its chosen corporate colour—teal.

The first band that hired the equipment after the Abacab tour, was Texas band ZZ Top, and slowly the business started to build. Over the next four years over 800 VL1's were built, and a number of distributor deals were made to introduce the product into the European (via Samuelsons), Australian (Jands) and Japanese markets.

After the 6th generation of VL1's were completed, in the late summer of 1984, design started on the Series 200 system. A new console, called the Artisan, was designed, as well as two new luminaires: the VL2—a direct descendant of the VL1 and the VL3—a wash luminaire using a twisting dichroic filter system to create colours, based on that first used in the VL-Zero.

The Series 200 system was launched in 1987. Over the years the range was expanded to include the VL4, a more compact and brighter version of the VL3, and two upgrades of the original VL2: the VL2B and the VL2C. A smaller backup console was also launched, called the Mini-Artisan.

In 1989 Vari-Lite sued Syncrolite, Inc. and its owner and founder, former Showco president Jack Calmes, over alleged patent infringements. Calmes countersued, claiming that his former business partners had kept the development of the Vari-Lite system from him at the time of his departure, causing him to lose money when he sold his Showco stock. The case was resolved in Vari-Lite's favour.

In 1992 the first Series 300 luminaire was launched: the VL5 wash luminaire. Although not a technical leap of the same magnitude that previous models were, it was very well received by the market, because of its low rental cost, reliability, versatility and compatibility with DMX512 lighting consoles, in addition to the Artisan. By this time, the use of DMX to control intelligent lighting fixtures was becoming widespread, despite it not having been originally intended for this purpose.

In 1994, Vari-lite set up Irideon Inc. to manufacture and market automated lighting products to the architectural lighting market. Irideon was sold by Vari-lite to Electronic Theatre Controls in 1998.

In August 1995 Vari-lite filed a patent infringement lawsuit against competitor High End Systems, seeking unspecified damages and an injunction against the manufacture of the Status Cue system, including the Cyberlight and Studio Color luminaires.[8] The matter was eventually resolved out of court, in early 1999.[9]

In 1997 the company floated on Nasdaq (NASDAQ:LITE), selling two million shares, in a move which allowed the company to retire almost half its debt. 47 percent of the company remained in the hands of Genesis and Vari-Lite management. The company then began to buy back the franchises it had created in previous years and create new rental offices, which it called Vari-Lite Production Services (VLPS) agencies. The main difference was that the company now offered conventional, third party lighting equipment for rental, in addition to its own products.

In 1999, Vari-lite launched a patent infringement lawsuit against Danish lighting company Martin Gruppen A/S,[10] winning a preliminary injunction barring the import, sale and lease of the Martin MAC 500, MAC 600 and MAC 300 luminaires, along with the Case Series Controller, in the USA.[11] The injunction was vacated in August of that year, but re-entered the following month.[12] Martin responded by releasing updated products—the MAC 500SP and 600NT, which lay beyond the scope of Vari-Lite's patents.[13]

At around the same time, similar, patent-related lawsuits were launched against two Italian manufacturers, Clay Paky and Coemar, along with various other companies. Vari-lite was represented in these cases by Texas lawyer, Theodore "Ted" Stevenson, III.[14]

In 2002, The VARI*LITE luminaire manufacturing and sales division (brand, assets and intellectual property) were sold to the Genlyte Group.[15] The rental division of the company retained the console division of the company and continued to develop the Virtuoso console product line. The rental division (by this point called VLPS Lighting Services) was merged with the Production Resource Group (PRG) in 2004.

Very soon after the acquisition by Genlyte, a new range of Vari-lite luminaires was announced—Series 2000—beginning with the VL2416 wash luminaire. Series 2000 luminaires could only be controlled by DMX data and official technical support for all Series 100 and Series 200 products was withdrawn at around the time of their release.

In early 2008, the Genlyte Group owning the VARI*LITE brand, was bought by Royal Philips Lighting.[16] Under Philips' ownership of Genlyte, a brand new Vari-lite luminaire (the VLX wash) has been developed, which uses a cluster of high intensity RGBW LEDs as a light source. The luminaire was premiered in the Spring of 2009.

Since 1981, almost every major band has used Vari*Lites in their productions at some time, as well as TV, corporate events and even films. The company has won three Primetime Emmy Awards for technical achievement: in 1991, for Outstanding Achievement in Engineering, in the development of the Series 200 system; in 1994, for the development of the VL5 and in 2001 for Outstanding Achievement in Engineering for the Virtuoso console.

Historical perspective

For further information on the general history of moving light technology, see: Intelligent lighting—History

As with any cutting-edge technology which eventually becomes commonplace; it is often hard in later times, to imagine, convey—or sometimes even recall—the impact that such technology made upon its arrival. September 25, 2011 marks the 30th anniversary, of the first public appearance of a Vari-Lite system and—by definition—the beginning of the multimillion-dollar, moving light "industry" which grew from that moment.

Vari-lites and their many imitators revolutionised the way that stage lighting systems were designed, programmed and used; e.g. in the way that formerly innovative and original programming techniques—such as the use of Preset Focus positions (first seen on the Artisan)—have become a standard feature of most stage lighting controllers today. As a result, they have also had a wider influence on set design and the overall look of many stage productions, particularly concert tours.

Although it is true that the concept of colour-changing, moving light technology was far from new by the start of the 1980s and that other moving light systems—such as the Telescan by French company Cameleon and the Pancan in the UK—were being independently developed at around the same time; it was Vari-lite who were first to combine the relevant emerging technologies into a practical system, on a large scale; which could then be taken on a worldwide concert tour and set up in varying locations and environments, night after night, often over a period of several months. It was this achievement which ultimately led to the success of Vari-lite, pointed the way for those who followed and guaranteed the company's place as an innovator.

Control systems

From the very start, Vari*Lite consoles were computerised, transmitting digital multiplexed signals to the luminaires.

Series 100

Originally known simply as The Vari-lite System, Series 100 used a patented protocol based on RS-422, which sent positional, beam and colour information, via a rack-mounted computer, to up to 32 individual Vari-lite luminaires (later known as VL1s), at up to 30 times a second. Up to three computers could be linked together under the control of a single console, giving a maximum system size of 96 luminaires.

The transmissions were unidirectional, and the error checking was quite rudimentary, checking each transmission bit 5 times and applying the majority result. As the information was retransmitted multiple times each second, the result was no noticeable errors by the luminaires. However, the refresh rate of a full 96 channel system was visibly noticeable if, the low-numbered channels were rigged close to high-numbered channels (in Vari*Lite jargon, a "channel" referred to a whole device, regardless of how many parameters it had).

In order to distribute both power and data, 6 channel "dumb" repeater boxes were used. The cables carried both data and power. In order to meet safety standards, the data cable was rated at 600 v, to allow it to be used in 3 phase power applications. The channel number (also known as an address) was set with three thumbwheel switches on each lite and a common practical joke on the part of non-Vari-lite crew, would be to renumber random "lites" (this became a common way of referring to a Vari*Lite unit on both sides of the Atlantic).

The designation Series 100 was not applied until 1987, upon the release of the Series 200 system.

Series 200

By contrast, the Series 200 system was designed to employ a proprietary, bidirectional protocol. Each luminaire became "intelligent"—storing its own positional, beam and colour information, and reacting to a global "memory cue" command, so every luminaire reacted simultaneously (see US Patent No.5010459[17]). This overcame the limitations imposed by the processor power available at the time, on the maximum number of luminaires that could be controlled from one console.

The Series 200 system was introduced in 1987 and featured the VL2 and VL3 luminaires, controlled by the Artisan console, with power and data distributed to dumb repeater boxes by an ACS Rack. The repeaters gained three more outputs, making nine in total. Up to seven repeater boxes (63 luminaires) could be supplied by one ACS rack. Multiple ACS racks could be linked together, data-wise, with one acting as a master and the other as slaves.

Manchester encoding was used to improve transmission resilience and a polling system was introduced to get feedback (known as Reply Data) from each luminaire. Damaged cables and "chattering" lites could cause problems in larger systems, as they introduced noise into the reply data lines running back to the Artisan console, causing luminaires to appear offline. Although this did not normally affect the playback of cues, it could cause severe problems when trying to save and backup the system data onto the 1.44Mb, 3.5 inch floppy discs that were standard at the time.

Under Series 200, the number of controllable channels (i.e. luminaires) was increased—at least on paper—to 1000; but in reality, the practical maximum was around 400. The reason for this discrepancy, was that if a luminaire had not been polled for (and had therefore not sent) its reply data within a certain time, it would become regarded as "offline" by the Artisan console. In a system of over 400 luminaires, the limitations of the hardware in the Artisan, meant that it was not possible for the console to poll all the luminaires within the allotted time.

The performance of the Series 200 system was greatly improved over its working life, through a rolling program of upgrades, modifications and retrofits. Central to these were the various software versions, which progressively refined the programming features available to Artisan console operators.

The VL4 wash luminaire was officially added to the Series 200 luminaire range in 1991.

Series 300

By the end of the 1980s, the market for moving lights was firmly established—a market which had arguably been created single-handedly by Vari-lite themselves. However, the high cost of renting a Vari-lite system and the fact that they could only be programmed from an Artisan console, by a specially trained operator, were barriers to full realisation of market potential. Additionally, despite the protection afforded to Vari-lite technology through the use of patents, rival manufacturers were beginning to market competing moving lights; along with consoles which could control their functions using the DMX512 protocol. There were also general market concerns regarding the overall size and weight of moving lights in general, which limited the number of them that could be hung on a lighting rig and made them impractical for many small / medium scale productions.

The Series 300 system was developed to address these issues. Series 300 was not strictly a new protocol, but a development of Series 200 that moved most of the processing away from the luminaires and into the repeater box, thus creating the Vari-lite "Smart Repeater" (VLSR—see US Patent Nos. 5209560[18] and 5329431[19]). The VLSR is able to distinguish between Vari-lite Series 200 and DMX512 data signals, and can be controlled with either—although not both simultaneously (merging). Having identified the type of incoming control signal, the VLSR converts it into Series 300 data; which it sends to the luminaires, along with the 24V power lines required to drive the motors. Up to six Series 300 luminaires can be controlled via one VLSR, using Series 300 Smart Lamp Runs (SLR)

When controlled by a Series 200 data signal, the VLSR stored the cue information (in much the same way that Series 200 luminaires did) and transmitted the raw positional and colour information to the luminaires, as Series 300 data. In this case, the Series 200 input connector was used to supply both power and data. When controlled by a DMX512 data signal, all cue information is stored in and transmitted from the lighting console; with the VLSR simply acting as a translating device, which converts the DMX signal to Series 300 data in real time. In this case, the Series 200 input connector is used only to supply mains power to the VLSR, with DMX data being input via a separate, standard, 5-pin XLR connector.

The first Series 300 luminaire was the VL5 wash, released in late 1992, along with the VLSR. The VL6 spot luminaire was released in 1994 and the VL7 in 1998; with updated variants of all luminaires being developed, following their respective, initial releases.

Control consoles

Series 100 Prototype Control Console

Only one of these was ever built, and only had two control sections: Direct Cueing, where a memory number was entered on the keypad, assigned to the direct window and triggered by pressing the Go button, and Cross-Fade where two memories could be assigned to opposite ends of a pair of faders, and the luminaries would transition between cues. Each of the circuit cards in the system as well as the backplane of the system was hand wired, and the first operator, Dave Berger, one of the technicians who had built the unit, would take it out on tour with The Who and later with Paul Anka with the original seventeen 1st generation lites. The system was also used on The Kinks tour in 1983, then retired as new Series 100 Consoles and luminaires were built.

Series 100 Control Console

The production version of the Series 100 console was never given a name and was generally referred to as, "the Vari-lite console". It now boasted four control methods: Direct, X-Fade, Chase and Matrix. Chase allowed a consecutive number of cues to be run automatically, although the speed had to be set by hand, and matrix allowed you to program some cues to have their intensity levels split into eight groups. The total cue storage was 256 cues, with sixteen assigned to the matrix. The remaining 239 could be used by any of the other control methods. In addition, there were two banks of sixteen programmable colour buttons, called "Preset Colours", and the active control of the luminaires could be divided into two banks of sixteen groups.

Later software versions allowed "Selective Store" and a quirk in the software allowed you to completely wipe a cue memory in a group of lites, and then only store the colour or beam information. Triggering a cue saved in this way would simply overlay the colour or beam information of a lite without changing its position. By 1986/87 it was common to see a good operator using both direct and x-fade controls overlaid by a selectively stored colour or beam chase at the same time.

Luminaires

Prototypes

VL-Zero

The prototype VL-Zero (VL0) was a dichroic colour fading wash unit. The original is still in semi-working condition at PRG. The colour change mechanism worked by twisting dichroic filters into and out of the beam path. This design proved impractical for the profile spot-type optics of the unit planned, but the idea was later revived in the company's wash luminaires, beginning with the VL3.

Series 100 luminaires

VL1

The VL1 (Series 100) used dichroic filter, mounted onto three wheels with seven filters each, plus an open position. A fourth wheel was fitted with five beam apertures and two gobos. Pan and Tilt used servo motors, and intensity was controlled by an iris at the front of the head.

The Upper Enclosure (UPE—the "box" on which a moving head is mounted) contained the power supply for the lamp (the APS250) and a Data Receiver Card—a PCB which translated the cue information received from the console into low voltages; these were then (mostly) sent via a wiring harness to a servo amplifier card in the head, which provided the actual power that drove the motors. The Data Receiver Card also translated the lamp Start and Douse commands from the console and fed them to the APS, allowing the lamps to be switched on and off remotely, by the console operator.

The original choice of lamp—the GE Marc 350 projector lamp, a discharge lamp with a daylight colour temperature caused several problems and a less powerful, 250W lamp had to be substituted.

The Osram HTI 250 was selected as the replacement lamp for the new VL2 after the company experienced significant troubles with the original GE MARC350 lamp. Quality issues led to limited supplies of the lamp being available and the company did not want to base a new product on the MARC350. Vari-Lite eventually tried the HTI 250 in the VL1s for the same reason, lack of supply of good MARC350 lamps. They also tested the Philips MSD 250 lamp in the VL1 with some success. They had a projected lifetime of >1000 hrs, but by that time the VL1s were nearing retirement.[20]

860 units were built between 1981 and 1984. Most of them were destroyed, but some four units are reported to still survive, two at PRG and two built from spares are in private hands. Some units were stolen, and may also still survive.

Series 200 luminaires

VL2 / VL2B / VL2C /VL2D

The VL2 was a moving head spot luminaire, designed to replace the VL1 and make use of the bi-directional communication afforded by the Series 200 system. In addition to Pan, Tilt and Intensity, the VL2 featured two colour wheels, with 16 positions each (15 dichroic filters plus one open position for white—see US Patent 4800474.[21]) There was one (non-rotating) gobo wheel with 10 positions (9 gobos plus 1 open). The gobos could be easily swapped for custom designs—unlike the VL1. The gobos were mostly made from aluminium, fixed to a plastic stalk, but Vari-lite also developed a new type of glass gobo for use with the VL2 (see US Patent 4779176[22]).

There were two other new beam functions: A beam iris to alter the diameter of the beam and a movable, multi-element front lens to sharpen or soften the beam edge.

The VL2 used an HTI-250 arc source, similar to that in the VL1, driven by an updated APS250 lamp power supply.

To this day, few—if any—automated spot luminaires, have been able to match the speed of colour and gobo change achieved by the Vari-lite VL2 and its direct descendants.

As with all Vari-lite products, the VL2 range was subject to a rolling programme of improvements and retrofits, designed to increase the reliability of what was still, in many ways, cutting-edge technology. In particular, the design of the original APS lamp power supply was notoriously unreliable but was ultimately cured by the application of the "X-mod" upgrade, which—with additional tweaks to the lamp ignitor card—vastly reduced the number of APS-related and lamp strike problems. Upgraded APS units were suffixed with "-X".

The VL2B saw the light source upgraded to a HTI-400SE, short arc discharge lamp, driven by the upgraded APS400 PSU. A very pale blue dichroic filter was replaced with 3200°K tungsten correction and the beam iris motor replaced with one of a higher resolution. VL2B luminaires can be distinguished by the absence of ventilation louvres on the rear panel of the head; which were replaced by a hinged panel, through which to access the new lamp base for bulb changes and line-up.

The VL2C further upgraded the light source to 600 W, driven by an APS600-X lamp PSU. The internal ventilation system was accordingly redesigned to better cool the head—especially the colour / gobo wheels and the beam iris leaves were upgraded for better heat resistance. The speed of the cooling fan was also increased—which led to some complaints (especially from TV studios) about noise. Detachable, external baffles were designed to cover the ventilation grilles in the side of the luminaire's Upper Enclosure (UPE), in order to deal with this issue; but could occasionally cause overheating in warm environments, leading to lamp shutdown.

The VL2C also featured an upgraded processor board, to better handle the demands made by extra features offered in later versions of the Series 200 operating system software, such as the application of timing values (rather than a simple speed) to the various functions. The VL2C can be outwardly distinguished by the presence of ventilation louvres to the rear of the top and bottom head covers and by a smaller, hinged colour / gobo access hatch, secured by a quarter-turn Zeus clip (previous versions featured a sliding hatch).

In the late 1990s, a modification was applied to the VL2C, which allowed it to be controlled from DMX512 lighting consoles, via a Vari-lite Smart DMX unit. In the UK, the remaining VL2Cs were eventually sold off to various lighting rental companies. Some may still be in existence, other than any kept for exhibition / archive units; but the difficulty of sourcing spare parts means that a significant hire stock is unlikely to be maintained in the long term.

VL2D: With the end of production of the 600HTI lamp, some vl2C was converted by EML/PRG with 700MSR lamp.

VL3

The Vari-lite VL3 was the company's first attempt to create a moving head wash luminaire, designed overall to light larger areas of a stage with softer-edged beams of light; in contrast with the tighter, often hard-edged beams produced by spot luminaires. The VL3 was built to complement the VL2 spot luminaire and released at the same time, in 1987, as a part of the (then) new Series 200 system. Externally, the luminaire was of an identical size and design to the VL2, save for the presence of a larger (6" / 150 mm), convex, slightly frosted lens—its key distinguishing feature. A wider range of lenses, with a variety of beam angles mimicking those found in PAR64 lamps, had been originally planned, but was not implemented on the VL3. The idea was later revived for the VL5.

Internally, the VL3 marked a return to the original idea of using twisting dichroic filters, to gradually vary the colour of the beam (see US Patent 4602321[23]). This was made practical by the simpler optics employed in a wash luminaire, which do not produce the same beam artifacts that the optics of a spot luminaire would, using this type of colour change mechanism. The subtractive, CMY (Cyan Magenta Yellow) colour mixing system designed for the VL3, featured three sets of three dichroic filters, each set independently rotatable; with the cyan filters at the rear, closest to the lamp and the magenta filters to the front. In their "open" position, the filters sat edge-on to the axis of the light beam, so that only white light emerged. By rotating the filter sets into the path of the beam, a wide variety of colours could be created—from light pastel shades, to deep saturated hues.

A similar mechanism, with three, frosted glass vanes in place of dichroic filters, sat in front of the colour mechanism and was used to provide variable beam diffusion / width control, from a narrow spot to a wide flood. Further beam width control was introduced, with the motorisation of the lamp base; which allowed it to be moved through the reflector, along the beam axis.

Another, major departure from the VL1 and VL2, was the use of a custom-made, tungsten lamp as the light source, which ran at a maximum of 53 volts and consumed 475 Watts. This was dimmed by a new type of lamp power supply—the IPS, with I standing for Induction, instead of Arc.

Despite allowing lighting designers and programmers to create the kind of gradual colour changes and soft-edged washes which were unachievable with the VL1 and VL2, the VL3 was not a long term success; mainly due to the tungsten lamp not being bright enough to handle longer throws, especially when set in darker colours. This compromised its ability to provide frontal illumination, reducing its role to mostly backlighting and beam effects. The VL3 began to be replaced by the VL4 from 1991. There may be a one or two left in existence, for exhibition / archive purposes, but the vast majority had been converted to VL2B luminaires by the end of 1994, which in turn were later upgraded to VL2Cs.

A large number of VL3 luminaires can be seen surrounding the central, circular screen, in videos of Pink Floyd's Delicate Sound of Thunder tour.

VL4

Marketed under the strapline, Smaller, Lighter, Faster, Brighter, the Vari-lite VL4 was the company's second moving head wash luminaire, designed to replace and improve upon the VL3. It was first made available for rental in 1990.

At roughly half the size and weight of its predecessor, the VL4 did much to address market concerns regarding the size and weight of moving lights in general. A customised 400W short arc discharge lamp, updated from the one employed in the VL2B and coupled with a chemically brightened aluminium reflector, ensured that the output far exceeded that of the disappointing VL3.

The subtractive, CMY colour change mechanism was a reduced-size version of the one used in the VL3, but beam diffusion was handled by a tambour-inspired design; with motor-driven, vertical slats of increasingly diffuse glass, that were drawn (internally) across the front end of the luminaire from both sides (see US Patent No. 4972306[24]). As with the VL3, further beam width control was achieved by moving the motorised lamp back and forth inside the reflector, along the beam axis.

Intensity control was provided via a mechanical shutter (the discharge lamp being non-dimmable). A second, "strobe" shutter, designed to snap open and closed as fast as possible, was incorporated into the intensity mechanism.

The VL4 also featured a 12-bit Motorola processor, over the 8-bit one used in the VL2 and VL3.

Despite being a technical improvement over the VL3, the small size and compact design of the VL4 led to a number of reliability issues—particularly with overheating. The densely constructed and relatively front-heavy head of the luminaire was also prone to overshooting (and then bouncing back to) its intended position at the end of fast movements. Many problems were addressed in a major upgrade programme, carried out over several weeks in the early 1990s, which featured over 135 modifications to the design. These ranged from the simple placement of a blob of rubber sealant somewhere in the luminaire, to the wholesale stripping down, extensive modification and total rebuilding of the Pan and Tilt mechanisms, to combat the overshooting problem.

The new, compacted design of the APS400 lamp power supply suffered similar problems to the earlier APS power supplies, although these were mostly cured with the eventual application of the "X-mod".

Ultimately, the small size of the luminaire made it impossible to upgrade the light source to a brighter, 600 Watt lamp (as had been done with the VL2C upgrade). Increasingly bright, competing luminaires from rival manufacturers, coupled with continuing reliability issues and high maintenance costs, saw the VL4 largely replaced by the VL5 within a decade of the latter's release. Very few remained in service beyond the first years of the 21st century and fewer still are in existence today, except maybe a couple held for exhibition / archive purposes.

Series 300 luminaires

VL5 / VL5 ARC / VL5B

The VL5 was the third moving head wash luminaire to be produced by Vari-lite and was released in September 1992. It uses the Dichro-Tune radial CMY color mixing system (see US Patents 5073847[25] and 5186536[26]). This system gives smoother transitions between colours and more even pastel shades, than that used in the VL3 and VL4; but is slower in end-to-end travel and gives the fixture the unmistakable black dot at the front of the fixture. A fourth set of vanes carry diffused glass to soften / widen the beam. Unlike the VL4, there is no other beam control; although the native beam angle can be pre-set using interchangeable lenses, which mimic the beam angles found in PAR64 lamps (an idea first proposed for the VL3).

Design-wise, the VL5 responded to calls from entertainment lighting designers, for lighter, simpler, more reliable and (above all) cheaper moving light technology, which did not have to be controlled by a proprietary console. It was the first Series 300 luminaire, which could be controlled by either Vari-lite Series 200 data, or DMX512-A data, via a Vari-lite Smart Repeater (VLSR) box.

Whichever data type was used, the mains voltage tungsten lamp used in the VL5 is dimmed remotely; using standard, stage lighting dimmer technology. This considerably reduced the cost of the luminaire and removed the need for a large upper enclosure, it being possible to incorporate the remaining electronics in the yoke of the unit. The lamp itself was an updated design by Philips, strengthened to withstand the forces on the white-hot filament caused by high-speed movement of the head.

The VL5 was the first moving light to use "cold mirror" technology to provide a cool, high-intensity light beam, which could be placed close to objects and people, without burning them. The VL5s reflector is, in fact, a very large dichroic filter, which only allows infra-red light to pass through it, while reflecting the remaining visible light forward. The idea had been in use for some time before, most notably in MR16 halogen downlighter lamps, but never scaled up to this level. The prototype VL5 cold mirror reflector allegedly cost US$100,000 to produce. The idea works well in producing a cool beam output, but can raise the rear end of the head to flesh-searing temperatures, after just a few minutes' operation at maximum intensity.

The VL5 was the first convection-cooled moving light, requiring no fan and therefore producing almost no noise. This has made it a popular choice for television lighting and other noise-sensitive applications.

The VL5 Arc introduced a 575W discharge lamp to the design. As this could not be electronically dimmed, the diffuser vanes were replaced with black metal ones, which acted as a mechanical dimmer. Beam width control was initially carried out using an innovative "Liquid Lens"—again designed by Jim Bornhorst (see US Patent 5774273[27])—which pumped a liquid silica-based gel into a series of lentil-shaped cavities, set between two plastic membranes—thus altering their refractive index and giving a variable beam angle of 13–34°. However, this range fell short of that originally promised in the R&D stage and was not generally wide enough, to be useful for creating the kind of broad washes of soft-edged light, normally expected by users from this class of luminaire. The liquid lens fell further out of favour, after some users obtained the MSDS for the gel being used in the lens and expressed concerns at its potential toxicity. Following this, many VL5 Arcs were rented out without the liquid lens, using instead the same, fixed-focus range of lenses designed for the original VL5.

The original VL5 had offered a wider range of green shades than the VL4, but enabling it to do so had compromised its ability to produce pale, daylight and "steel" shades of blue—which are more useful to lighting designers, especially those working in Theatre and TV. The VL5B featured an alternative filter set, which restored the ability to produce pale blues, but reduced the overall number of useful colours available—especially darker, more saturated shades in the blue-green range. As a result, the VL5B is mostly used in Theatre and TV productions, where its specialised colour range is more often specifically required. The VL5B uses the same, 1000W tungsten lamp as the original VL5, powered by remote dimmers.

The VL5 has proved to be Vari-lite's most long-lived product and is one of the most popular stage lighting units, of any kind, ever made—with over 3,500 built. Its simple workings, ease of maintenance and overall reliability, have made it a favourite among lighting crews for almost twenty years and—as of 2010—it is still readily available for hire from a number of rental companies; continuing to illuminate stages around the world. The smooth, elegant, early-1990s design—informed by the classic PAR64 Parcan lantern—has not dated appreciably and still looks "current" when used alongside more modern equipment—to the extent that the basic look of the head has been carried (along with that of the VL6), into many, post-Series 300 Vari-lite luminaires.

VL6 / VL6B / VL6C / VL6C Plus

The Vari-lite VL6 was designed to complement the VL5, as a simple, lightweight, cheap-to-hire, moving head spot luminaire; but did not appear on the market until mid-1994—almost two years after the VL5. As a Series 300 luminaire, it could be controlled either by Vari-lite Series 200 data or DMX512, via a Vari-lite Smart Repeater (VLSR) unit.

The unusual "cyclops" design carried just two wheels: one for colour and one for gobos, each with 12 positions (including 1 open). The dichroic filters and gobos in the VL6 were interchangeable between the two wheels. With gobos set in both wheels and placed in the beam path, it is possible to "morph" between them, by adjusting the focus of the motorised lens (See US Patent No. 5934794[28]). Placing dichroic filters in both wheels, allows additional colours to be created beyond the basic palette afforded by a single wheel, although this potential has not been widely explored.

A new process of laser-etching very high resolution designs, onto the very small glass gobos designed for the VL6, was developed and patented by Vari-lite (see US Patent No. 5728994[29]).

A custom HTI-400 discharge lamp was once again chosen for the light source, requiring mechanical dimming and fans to cool the head of the luminaire; although these were smaller and considerably quieter, than those used in previous luminaires. As with the VL5, a dichroic, "cold mirror" was used as the reflector. Like the VL5, the VL6 had no upper enclosure and a new, modular, rack-mounted version of the APS power supply (the APS6) was designed to remotely power the lamps, via VLSRs. Six APS6 units could be mounted in one rack at a time.

A dimmer dimmer module (the C3) with the same overall form as the APS6 was also designed, with the intention of allowing the lamps of VL5s and VL6s to be powered together, from the same lamp PSU rack, via a common VLSR. However, in Europe, the limitations of the C3 circuitry meant that insufficient voltage could be produced, to raise the 230V version of the VL5 lamp to its maximum possible intensity; leaving the output looking dim and yellow. There was also the potential for accidental connection of VL6 lamps to dimmed mains supplies on "mixed" VLSRs, which rendered the lamps instantly and permanently useless. As a result, VL5 lamps continued to be mostly driven by third party dimmers and VL6s by APS racks, with the two types of luminaire usually running on separate VLSRs.

The lightweight design of the VL6, meant that much faster moves were possible than with previous Vari-lite spots; although this was compromised by the weight added in the VL6B upgrade.

Performed in 1998, the VL6B upgrade added a wider aperture zoom lens, with a 13−35° range and an additional rotating gobo wheel, with 5+1 positions. This added considerable weight to the head of the luminaire and made it front-heavy, to the extent that a counterweight was required to provide balance and bolted to the outside of the rear of the head.

The VL6C upgraded the light source to 600 W, with commensurate measures taken to improve head cooling, heat resistance and to upgrade the APS6 lamp power supplies.

In December 2007,[30] The Production Resource Group (PRG) completed an upgrade of their entire stock of 1,200 VL6C luminaires to accept a 700W short arc discharge lamp. Modifications to the airflow system were made to improve the reliability of circuit boards and motors, with upgraded wiring and connectors for all motors and pan/tilt mechanisms. Improvements to the ignitor reduced the hot restrike time from 8 minutes to 1 minute and a new lamp douse switch was fitted, to allow lamp power to be disconnected at the luminaire itself. This upgraded version of the VL6C is referred to as the VL6C Plus.[31]

VL7 / VL7B

The VL7 spot luminaire marked a return to a much larger design. As a Series 300 luminaire, it could be controlled by either Series 200 data from an Artisan console, or DMX512 data from a third party lighting console, via a VLSR unit. The Philips MSR 700 SA lamp, with a colour temperature of 5600°K, was chosen for the light source and driven remotely, from newly upgraded APS6 lamp power supplies.

In keeping with its predecessors, the VL7 featured a number of innovations. First and foremost (at least from a marketing point of view) was the CVF colour system. This featured neither wheels nor twisting filters, but rather a pair of comparatively large, oblong, dichroic filter plates, which could be moved in the vertical and horizontal plane. Each plate carried three basic shades, carefully graduated to merge across the longer, horizontal plane. In the vertical plane, the three basic shades were progressively etched away with lasers, so that they were fully saturated at the top, but completely clear at the bottom. One filter plate carried the colours red, green and blue; while the other carried cyan, magenta and yellow. US Patent Nos. 5825548[32] and 5969868[33] describe the concepts behind the CVF colour system. Both patents make mention of a colour wheel and a fixed position wheel was included in the finished luminaire. This could carry both colours and/or gobos, but was mostly used for the latter. There was also a rotating gobo wheel, with a total of six positions and a strobe shutter, which could run at up to 7.25 Hz.

A further, more subtle innovation, saw the use of a new, collection optics system, that guaranteed a much flatter and more even beam than had been produced by previous Vari-lite luminaires, which were prone to "hot spots" if not set up correctly. The ideas behind this component of the VL7 were described in US Patent No. 6123436[34]

The quest for optical excellence continued with the near projection-quality zoom lens; which featured an unprecedented 8:1 ratio, in the shape of a 5–40° beam angle range—a feature made more remarkable, by its highly compact design (see US Patent No. 6046861[35]).

Despite these innovations and Vari-lite's previous experience, development of the VL7 was fraught with problems; originally unveiled in 1997, it was not released onto the market until 1998. Behind schedule, over-budget and not fully tested, the initial run of VL7 luminaires immediately fell victim to a wide range of teething troubles, for which—in most cases—there was no immediate cure. This left technicians only able to replace failed parts, rather than fix the problems which were causing them to fail. For example: a problem in the CVF, which caused the teeth to soften and become stripped from the belts that drove the filter plates, was traced to their drive gears, which had been made of a material with a high Specific Heat Capacity. Once this was understood, the gears could be changed, but not before several hundred belts had already required replacement. Further problems with the CVF caused cracks to appear in the (expensive) filter plates, although this did not always immediately affect the quality of the beam output.

Even when the CVF's mechanical bugs were cured, the fact remained that it often travelled through a range of green-coloured shades, in between the start and end colours of a change. Although all additive (RGB) or subtractive (CMY) will produce a tertiary colour—which may sometimes become visually dominant, in an aesthetically displeasing way—when cross-fading between a primary and secondary hue; it is always a product of and therefore more likely to harmonise with, the hues at the start and end of the colour change. Green was not regarded by users as a pleasant alternative to this and although a programming workaround was developed by operators, it was a time-consuming process to apply to multiple cues, that slowed down the speed of colour changes.

The luminaire had been released before the new, Series 200 software version required to control it from an Artisan was completely ready and—to begin with—it could only be controlled as a DMX luminaire, from a non-Vari-lite console.

Maintenance was complicated by the location of some sub-assemblies in the luminaire, the Pan unit proving especially difficult to replace.

The VL7 also featured more cooling fans than previous Vari-lite luminaires—a total of four and despite marketing claims of "virtually silent operation", the noise they produced did not go unnoticed by users.

The VL7B replaced the fixed colour / gobo wheel, with a four-leaf motorised shutter gate, which could be used to mask the edges of the beam and could be rotated by 50°. The maximum speed of the strobe shutter was also increased slightly, to 8 Hz.

The VL7 design was not a long-lasting success—certainly when compared to its Series 300 stablemates. Its unwieldy shape, size, weight and noisiness, plus the difficulty of maintenance and early unreliability, combined to make it unpopular with lighting technicians, operators and designers alike. By this time and despite Vari-lite's vigorous defence of their patents, there was a ready choice of alternatives available from competing manufacturers, which offered the same functions and brighter outputs. Many—if not most VL7s—were eventually returned to the VLPS agencies by sub-distributors and rental associates, to be hired only if specifically requested for a production.

Series 2000 luminaires

VL2000 Spot luminaire

Similar to the VL2416, the VL2000 spot series was available for outright purchase rather than rental only. The range began with the VL2201 spot fixture in the early 00's

VL2201

This was essentially a DMX version of the popular VL6b featuring an Upper Enclosure (UPE) housing the arc power supply for the MSR400 short arc lamp and low voltage supply for electronics and motors. The lightweight luminaire featured a 11+1 slot fixed gobo wheel, the same as the VL6 range, 5+1 slot rotating gobo wheel, edge control, 3:1 zoom, 11+1 slot colour wheel and single blade dimmer mechanism which could also function as a strobe.

Similar to early series 200 and 300 fixtures, the colour and gobo wheel speed is exceptionally fast allowing for effects that can't be achieved with other brands of spot fixture. Electronic focus allows for morphing between gobos.

The 2201 fixture has a smooth cold mirror reflector with lamp adjustment allowing for a flat or peaked beam.

VL2202

The VL2202 luminaire was very similar to the VL6c fixture. Specification was the same as the VL2201 except it featured a 19-35 degree 3:1 zoom range, a faceted cold mirror reflector for a perfectly flat beam, and a MSR700 short arc lamp for higher output. Vari Lite produced an upgrade kit for 2201 fixtures to allow them to be converted to 2202 fixtures[36]

The VL2201 was discontinued and the VL2202 renamed as the "VL2000 Spot".

VL2000 Wash luminaire

The VL2000 Wash fixture began life as the VL2402. They were renamed as the VL2000 wash the same time as the spot range was renamed. The VL2000 wash is the same size and design as the spot range for a consistent hanging configuration across the range. The fixture features a MSR700 short arc lamp, the same exceptionally fast 11+1 slot colour wheel, as well as a three-wheel CYM colour mixing system to allow for a nearly unlimited range of colours. This more traditional wheel mixing system differs from the previous Vari Lite Dichro*Tune radial colour mixing system employed in the VL5 and VL2416 wash fixtures.

The fixture has a single blade dimmer system, which allows for strobe effects, as well as zoom optics for a 12 to 57 degree beam angle.

The VL2000 wash is a DMX only fixture.

The VL2000 range of fixtures are discontinued and replaced by the VL2500 range, which feature colour mixing on spot and wash, higher torque pan and tilt motors, and an improved glass dimming system. The VL2500 range is still a current product.

Many service parts are compatible between the VL6 through to VL2500.

VL2416 Wash luminaire

Despite its numerical designation, this was the first new luminaire to be produced following the VL7 and hence became unofficially known as the "VL8" among American crews. The VL2416 marked a major sea-change in the Vari-lite business model, in that it was the first Vari-lite luminaire that could actually be purchased. Previous luminaires had (in)famously been available for rental only.

The head was closely based on that of the VL5 Arc, with radial CMY colour mixing and mechanical shutter dimming fast enough to also provide strobe effects.

The liquid lens was discarded and beam width controlled instead, by a new type of zoom optics(see US Patent 6809869[37]). This uses two plates of glass; one with a surface covered in several dozen, small (<10 mm), convex lenses and the other moulded with corresponding, concave depressions, into which the lenses precisely fit. When the plates are brought together, they effectively form a flat piece of glass, through which light passes unaffected. Moving the plates apart increases the angle of the beam, producing a very wide range of angles (5–55° in this luminaire) over a very short range of travel (<25 mm)—leading to a compact design with rapid operation (1.2 seconds end-to-end). A similar system can be seen in operation on some, early 21st-century LED stage lighting fixtures, with a variable beam angle function.

As this was a self-contained luminaire, the Upper Enclosure (UPE) was restored to the design, to carry the lamp power supply and DMX related electronics.

The VL2416 could only be controlled with DMX data. There was no facility for control from a proprietary Vari-lite console.

Other products and accessories

VLM

The VLM (Vari*Lite Mirror) was a result of a brainstorming session to try and solve the problems of never being able to offer every possible luminaire in an automated yoke. Vari-Lite designed a unit which was basically a two sided metal mirror mounted inside a Series 300 yoke. The tilt end stops were removed giving the unit the ability to spin continuously on that axis.

The units were used with much success on a series of Belgium TV shows where they were used in conjunction with a series of Robert Juliat 1200w profiles. However, a limited number of units were produced and they never became a mainstream product.

VLDi

The VLDi (Vari*Lite Dimmer interface) was a 96 channel 0−10v analogue interface between a conventional dimmer unit and the Series 200 control system. Each unit took up 100 of the 1000 available control channels, which gave the Artisan control console considerable potential. However, in many cases at the time the Lighting Designer on a show and the Vari*Lite operator were different people, and so many designers opted to retain the conventional lighting console. As well as this, the Artisan had been designed to control moving lights and did not provide many of the tools that conventional lighting desk operators had come to use.

The final nail in the coffin for the VLDi was the mass migration of the lighting industry to the DMX512 protocol.

The "i" in the VLDi acronym is still generally included in all verbal and written communications referring to the product. This is done to avoid potential confusion with the initials of Vari-lite Deutschland (VLD).

Mini ACS Rack

A single-output version of the Series 200 ACS Rack, designed mainly for test purposes.

Smart DMX

Introduced to replace the obsolete VLDi, the Vari-lite Smart DMX unit converted Series 200 data into DMX512 data, allowing control over conventional, third-party dimmers, from Vari-lite's proprietary Artisan console. This was used mainly to control dimmers which were powering the lamps of VL5, but also to control "conventional" portions of stage lighting systems, without the need (and cost) of a second console and operator.

Floyd Droid

A custom-built effects unit, designed for Pink Floyd's Delicate Sound of Thunder tour. Four were built and respectively nicknamed Manny, Moe, Jack, and Cloyd.[38] They featured arrays of motor-driven mirrors, and (mostly) scanned multiple, tight beams of light over the audience; while avoiding potential hazards to vision, associated with producing such effects using high-power lasers.

Irideon Inc.

History

Irideon, Inc. was a subsidiary company formed by Vari-lite in 1994, to target the architectural lighting market by offering colour-changing luminaires, able to dramatically illuminate buildings and outdoor structures in ways which—until then—could only be imagined.

Two Irideon luminaires were initially produced: The AR500 and the AR5.

Irideon Inc. was sold to Electronic Theatre Controls (ETC) in November 1998; as a result of the difficult conditions experienced by Vari-lite, during their first year of trading on the stock market.[39] Under ETC's stewardship, the AR50 was completed and a two new luminaires—the AR6 and AR250—were created.

Manuals for some Irideon luminaires are still available from ETC.

Irideon Luminaires

In chronological order:

AR500

A large, metal-cased luminaire, designed for outdoor use and finished in a grey powder coat.

The Pan and Tilt functions were not motorised, so the luminaire should perhaps not be considered as a true moving light.

Colours were created using the same, radial DICHRO*TUNE mechanism that had been developed for the VL5. As with the VL5, there was also a set of diffuser vanes to alter the beam width. A further set of black metal vanes were used to control intensity, as the luminaire employed a 500W discharge lamp as a light source, driven by an internal lamp power supply.

AR5

A much smaller luminaire, with a head approximately 300mm in length, available in a black or white finish and designed for indoor use. All functions were motorised, including Pan and Tilt, making the AR5 a true moving light.

Colour, Intensity and Diffusion were handled by miniaturised versions of the mechanisms used in the AR500, using just eight vanes per set, instead of sixteen.

The light source was a 35W discharge lamp, powered from an internal supply.

AR6

A recessed, non-moving version of the AR5. Mounted inside a case designed to fit within the area of a standard ceiling tile and intended for use in downlight applications.

AR50

A larger version of the AR5, with all functions motorised. Development was apparently begun under Vari-lite ownership of Irideon and completed by ETC.

AR250 / AR250C

A smaller version (plus variant) of the original AR500, with non-motorised Pan and Tilt and a 250W discharge light source.

References

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