Whether you are a lighting designer, technical director, or facility manager, staying informed about the vast and evolving assortment of lamp alternatives and ANSI codes available for everything from aisle lights to cyc lights is enough to make your head spin. Energy consumption, lamp life, color temperature, voltage, size, efficacy, cost, and color rendering are just some of the many distinct lamp characteristics that can affect performance, not only for the most demanding of theatrical fixtures but even for those unpretentious downlights in the dressing rooms. Global manufacturers including Philips, General Electric, Osram/Sylvania, and Ushio introduce lamps each year which provide new creative opportunities, in addition to cost savings and better performance, provided you know how (and when) to take advantage of them.
Facility managers take note…according to Osram/Sylvania, replacing aging magnetic ballasts and T12 lamps with electronic ballasts and Octron™ T8 lamps in grid worklights, hallways, and offices may save up to 40% in energy consumption over the life of the lamp. For a dressing room, perhaps, General Electric manufactures a 29W, 10,000 hour compact fluorescent medium screw-base lamp that can directly replace a 100W, 750 hour incandescent lamp, matches its color temperature and dims down to 10%. Ushio offers a 50W MR16 lamp with a specially coated reflector rated at 10,000 hours that doubles the longevity of most low voltage track lighting or lobby downlights using this 12 volt lamp class. These are just a few of the many innovative lamp designs which offer both economic and functional benefits to the theatrical and architectural community.
“With lamps, people often lose sight of the big picture,” says Dan Imfeld of LE Nelson Sales, a veteran distributor of stage/studio lamps nationwide. “For example, let's look at the General Electric PAR-64. Someone will purchase an FF-series lamp (very narrow to wide flood) which costs, say, $20 and lasts 1,000 hours, instead of the Q1000 lamp, which costs around $32 and lasts 4,000 hours, usually based purely on price. Sure, there is a slight color temperature difference (200° Kelvin), but that may not be as important as lamp life, especially in permanent installations or long-running shows.”
“Theatre designers have a tendency to use what they're most familiar with,” notes Dawn Hollingsworth of Visual Terrain, “and everyone tends to ignore the balance of short-term initial costs versus long-term maintained costs.” Richard Hoyes, a theatre consultant at Fisher Dachs and Associates in New York, agrees, citing as an example the firm's recent design work on Hill Auditorium at the University of Michigan. “During our preliminary review process with the client, we were asked to specify a lighting package consisting mostly of traditional PAR-64 fixtures,” he explains. “Instead, we recommended ETC's Source Four PAR as an alternative, since we felt that a smaller lamp with a more compact filament would offer our client better overall control and performance.”
“Unquestionably, the HPL lamp is the single biggest thing that has happened to our industry in 20 years,” says Karl Haas of Gallegos Lighting Design. Haas, whose experience includes both theatrical and architectural design, adds “Usually, our minimum life requirement is 2,000 hours, so we tend to specify only the HPL/X series lamps on our projects.”
In response, manufacturers such as Osram, Philips, and Ushio have stepped up the pace. Ushio recently introduced several new long-life lamps for the Source Four including a HPL575/120X+, HPL750/115X, and for competitive ellipsoidals, a long-life 575W FLK with the medium two-pin base. “With the Ultra Plus products, we've been able to increase uniformity and overall brightness by up to 20%, particularly in the narrow beamspreads such as the 5° or 10° range,” says senior sales manager Gary Kirsch of Ushio.
“Theatre designers have a tendency to use [lamps] they're most familiar with, and everyone tends to ignore the balance of short-term initial costs versus long-term maintained costs.”
Dawn Hollingsworth, Visual Terrain
Osram has also extended its range with the Ultra Plus UCF (ultra-compact filament) product line starting at 375W up to a maximum of 750W, and Philips has recently announced its Broadway series of stage and studio medium two-pin base lamps featuring P3™ technology. “P3 allows us to burn the lamps at a much higher pinch temperature,” explains Richard Scott, marketing manager at Philips Lighting, “which does not provide a longer rated life, but in fact increases the actual life expectancy of the lamp on average.”
All Those Variables
Unfortunately, specification criteria such as rated life of a lamp, often defined as the number of lamp burning hours to the median life expectancy, is somewhat misleading. Among the many variables that can affect individual lamp performance are ambient air temperature, dirt accumulation, sudden physical shock or vibration, and input voltage to the lamp, which varies as a function of both dimming and line loss due to resistance from electrical wiring.
Some entertainment and architectural dimming systems allow precise adjustment of a trickle voltage to reduce electrical shock from inrush current. Circuit or rack-wide adjustment of dimmer output voltage can also compensate for a voltage drop across the dimmer module or line loss due to the length of the secondary wiring. “Designers should also be aware that dimming below about 85% will interrupt the halogen cleaning cycle in stage and studio lamps,” cautions Scott, “and without maintaining at least 250°C on the bulb wall, the lamp will begin to blacken and may fail prematurely.”
Even with this caveat, halogen technology has tremendous efficiency advantages over more traditional incandescent lamps, and as a result, the life expectancy of theatrical products such as color filters and pattern templates can be extended as well. “Combined with the new General Electric 650W T3 HIR lamp, we've seen nearly a 25% reduction in heat measured at the filter, from 420°F down to about 350°F,” says production manager Amé Strong at Special F/X Lighting. “These lamps allow color filters to last substantially longer.”
“On a recent theme park project, we installed our filters in Strand Coda fixtures facing straight down, which were lamped down from the standard 500W to the GE 350W T3 HIR. By maintaining the operating temperature below 300°F, we guarantee at least a full year of life for our filters,” notes Strong. GE offers these lamps in both the 3,000°K and 3,200°K range as direct replacements for higher wattage architectural and theatrical halogen T3 lamps, such as the conventional FDN and FFT groundrow and cyc lamps.
Many designers would like to see halogen technology expanded into other products as well. “To date, I don't understand why we don't have more 4,000-hour halogen lamps available to us,” says theatre consultant and designer Larry French of Auerbach & Associates. Lighting designer Tom Ruzika, principal of the Ruzika Company, agrees, and adds, “We need more lower-wattage halogen lamps with a longer rated life that provide a variety of beam options, such as a VNSP PAR. You still can't achieve that tight, narrow rectilinear beam using a Source Four or Altman StarPar, and in an exterior application such as lighting the corner edge of a 10-story building…there just aren't too many options if you need to dim it or you want the look of incandescent lighting.”
“And what about theatrical fresnels?” asks French. “Why aren't we able to use 575W lamps in these types of fixtures, which would allow a theatre to inventory the same lamp? Of course, this wouldn't work in many older fixtures, since the filament has to be in the right place, but the optics could probably be adapted for a new fixture design.” Hollingsworth adds, “For a tall theatrical application using 8" fresnels, we'd love something that can provide a broad wash with a decent lamp life, such as a 2,000-hour version of the BTN lamp.”
As with any business, however, demand dictates supply. “To develop a new lamp for a product like an 8" fresnel would require a certain sales volume for any manufacturer,” says Scott, “and that is something that would have to be taken into consideration. In designing lamps, you always have to ask what you're willing to sacrifice. There's only so much light versus so much life, and finding that correct balance is always a challenge.”
What's Out There
For more permanent lighting applications ranging from retail stores to theme parks, low wattage ceramic metal halide lamps are “very popular,” says French, “and they're being taken quite seriously by the design community.” Introduced by Philips Lighting in the mid-90s as the MasterColor™ series, they quickly migrated into all types of equipment, including theatrical ellipsoidals and PAR fixtures. These smaller scale metal halide lamps offer a rated lamp life in excess of 6,000 hours, a relatively high CRI, and a color temperature that approximates incandescent lighting. “The CDM lamp is stronger in the red spectrum, which is traditionally lacking in metal halide lamps,” says Scott.
Several other manufacturers have introduced competitive products, including the CMH™ series lamps by General Electric and Osram/Sylvania's TrueColor™ products. “For theatrical applications, there is a huge savings in both maintenance labor and energy costs when comparing the 150W T6 metal halide lamp versus the 575W HPL lamp,” says James Lapointe, product manager at Osram/Sylvania. “True, the initial price is still considerably higher compared to a halogen lamp, but as more people convert to this type of lamp, we hope to see both lamp and ballast prices come down.”
“We're definitely gravitating toward metal halide lamps not only in PAR fixtures, but also in theatrical fixtures, such as the Source Four and the Strand SL,” says Ruzika. “Sadly,” remarks French, “theatrical designers seem to recall paying outrageously high prices for HMI fixtures, so I think the cost of the metal halide ellipsoidals doesn't surprise them.” Hollingsworth is quick to add, “Until we stop seeing distorted prices for theatrical equipment used in permanent installations, the up-front cost will still limit the popularity and availability of these fixtures, but no one would argue that these lamps offer a lot of advantages.”
Theatrical and architectural designers seeking to create washes of colored light for interior or exterior applications without an accessory color filter have more choices as well. Venture Lighting manufactures pre-colored metal halide lamps in a variety of wattages and colors ranging from 150W to 1,000W, and Ushio Lighting recently announced a new series of colored metal halide lamps rated at 8,000 hours available in either 400W or 1,000W versions. For use on a smaller scale, Ushio also distributes MR-16 lamps with integral, colored dichroic filters for decorative or specialty applications.
The R&D efforts of lamp manufacturers small and large continues to move forward at a dizzying pace. Lamps keep shrinking in size and are becoming more sophisticated, even as fixture manufacturers rush to develop new applications for miniature bi-pin and reflectorized products in commercial, landscape, and decorative lighting. Eye Lighting, a division of Iwasaki, recently debuted a tiny MR-8 lamp that operates at 12V, Osram/Sylvania introduced its Capsylite™ G9 lamp as the world's smallest halogen 120V lamp that doesn't require a transformer, and GE has just announced a 21W MR-16 lamp with a built-in transformer and medium screw base rated for 5,000 hours. “Thanks in part to the Internet, even a niche distributor such as Fine Art Lighting, which distributes specialty frosted PAR-38 lamps made by Litetronics for museum and exhibition lighting, can introduce its products to a wider market of specifiers,” says Haas.
The continuing evolution of the Internet has certainly done much to expand the availability and timeliness of information on new and existing lamp products worldwide, but is there still room for improvement? “I think for our industry, manufacturers need to promote more global thinking,” Hollingsworth explains. “If I want to use a wall washer or miniature floodlight that takes color and barndoors in an attraction here, I often find that I can't use the same product overseas because there is no equivalent 230V lamp available. It would be great if manufacturers could list all the lamps that are available worldwide in a given category, so that we can try to keep some sense of consistency in the projects we design.”
‘We'd love to see better international specification and documentation standards among lamp manufacturers, because keeping up with the accuracy of the lamp data and making comparisons among all the different types of lamps we use is practically a full-time job in itself,” says Haas, adding, “and I've already got a job.”