Leitner's Cinematography Corner

Shadowstone’s Paul Distefano demonstrates ARRI’s compact LoCaster, with onboard selection of six color temperatures from 2800K to 6500K and continuous dimming.
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All photos by D. W. Leitner

NAB’s show floor last April signaled new directions in LED lighting. I’ll get to them below, but first a few thoughts on the evolution of electric lighting itself.

We complain we live in a time of dizzying change, but the 1880s were equally disorienting. Edison had patented his carbonized filament and Eastman his flexible roll film within a few years of each other. Electric lights, practical photography, motion pictures had arrived all at once it seemed. Modern times at mach speed.

It’s happening again, as digital imaging eclipses photochemical and filaments white-hot from electrical resistance yield to cool, compact fluorescent lamps (CFLs) and LEDs five times as energy efficient.

In fact Edison’s familiar screw-in bulb is being phased out around the world. I was in Havana in 2006 when Cuba banned incandescent bulbs and required their replacement by CFLs. Brazil followed suit, joined by the United Kingdom with a 2011 deadline and the European Union with a staggered schedule.

Even the United States has climbed aboard. The Energy Independence and Security Act of 2007 mandates that general-purpose incandescent lamps match CFLs in energy efficiency by 2020. (Physics makes this impossible, but tell that to a legislative body which conceives of laws, natural and otherwise, in terms of loopholes and attachments.)

Litepanels LP-1×1 at Shadowstone. Left knob provides continuous adjustment between 3200K and 5600K. Right knob provides continuous dimming.

Like the European Union’s mandate, the U.S. mandate excludes, for the foreseeable future, special-purpose incandescent bulbs such as those used in appliances, projectors, and motion picture lighting. No need to list those Blondes, Totas, and Mole Fresnels on eBay, at least not yet.

(Read this superb obituary for the incandescent bulb by Jane Brox, author of the new book, Brilliant: The Evolution of Artificial Light.)

CFLs, in turn, are at best a stopgap on the road to reduced energy needs. Slow starts, flickering, humming, phosphor aging, ballast failure, fragile glass, mercury vapor, complex dimming circuits—drawbacks to all fluorescent lamps–are circumvented by solid-state LEDs.

Venerated name in motion picture lighting embraces LEDs at Shadowstone. Mole-Richardson’s sturdy MoleLED 12-Pack softlight contains 240 OSRAM LEDs. One head each for 3200K and 5600k, both dimmable.

The writing on the wall is therefore clear as LED illumination itself: our everyday lit environment—interior spaces devoid of natural light—is poised at the brink of an historic leap to solid-state lighting.

(Outdoor areas at night are already lit by energy-efficient low-pressure and high-pressure sodium vapor lamps, up to twice as efficient as fluorescent. So what if they’re yellow/pinkish with the worst possible Color Rendering Index? You can brush up on the basics of CRI here.)

LEDs deliver white light using one of two methods: 1) grouping individual red, green, and blue LEDs (sometimes additional colors) into tight clusters, with a collateral benefit that tint or color temperature can be trimmed by adjusting R,G,B values, and 2) employing blue or near-UV LEDs to excite phosphor layers that emit white light. The near-UV approach is similar to fluorescent, with similar spectral distribution.

Shadowstone supplies architectural LED floodlights like this Philips eW Reach Powercore, bright enough to light a building facade. An RGB color version, ColorReach Powercore, is popular for deep-color architectural illumination.

For those of us who do motion picture lighting, there’s the rub: a discontinuous spectrum and resulting CRI that often falls short.

Once before, with the introduction in the 1980s of HMIs and Kino Flos, we encountered the anomalies of discontinuous spectra. The purpose of HMIs and Kino FLos, respectively, was to mimic daylight or blend with existing 3200K or 5600K sources while cutting power requirements 75%, perhaps eliminating location tie-ins.

These however were professional lighting technologies touting refined mixtures of rare earth gases (HMIs) or phosphors (high-frequency fluorescents) finely tuned for precise correlated color temperatures and maximum CRIs. They weren’t predicated on technology under development for mass markets.

ETC Selador series control software to match Lee Filters, as shown at Shadowstone. Selador Lustr LED light, same width as ARRI LoCaster, comes in lengths of 11, 21, 42, and 63 inches and uses 7-color LED arrays to achieve broadest possible spectrum.

Ever marvel at the cacophony of cool white, warm white, “daylight,� and indeterminate fluorescent hues in the average institutional ceiling?

I doubt tomorrow’s solid-state lamps will provide any more color consistency across the lit environment than today’s fluorescent tubes. When incandescent bulbs someday become as antique as gas lamplight, so too will the standard orange glow they both once gave off. I suspect ours is a future lit hodgepodge, a jumble of tints in which a broken spectrum is the common denominator. (Anticipated by contemporary film & television lighting styles.)

I, for one, have relied on fluorescent Kino Flo fixtures for years, and more recently, LED units from Litepanels. I never go anywhere without a set of compact Litepanels Minis or Micros. I remain fascinated by luminaires I can hand-hold without burning my fingers, dim without shifting color temperature, run for hours off light-weight batteries, then slip into an attaché case.

Prism Projection’s RevEAL CW (Revolutionary Entertainment & Architectural Lighting) uses a simple lens to throw a bright, even field at Shadowstone. Color temperature of white is adjustable from 1800K to 10,000K. Colors can be output too.

With all this in mind, I prepped for NAB by attending an LED open house in March at Shadowstone Lighting in Clifton, New Jersey. Shadowstone is a rental and sales company that services film and theatrical productions in the New York City area as well as architectural projects. I was introduced to them four years ago through my interest in LED lighting, in which they were early players.

The open house in March took place at Shadowstone’s rental facility, a huge hangar with tall, neatly organized aisles of heads, stands, cabling, lifts, generators, a capacious repair department—you name it. Limitless shelves stacked with everything from tiny HMI Joker-Bugs to lumbering 18Ks and all manner of tungsten–open-face, soft, PARs, ellipsoidals, Fresnels—plus of course LED devices. Closest thing to a full L.A. lighting rental facility I’ve seen on the East Coast and worth a visit to explore.

A pair of Pixel RANGE PixelPar 44s at Shadowstone. LEDs are RGBA which includes red, green, blue, and amber, a popular combination for colorful architectural lighting.

On this trip I encountered the latest LED products from Lightpanels, ARRI, Mole-Richardson, Rosco, Philips Color Kinetics, ETC Selador, Pixel RANGE, The Light Source, Strong Entertainment Lighting, and Prism Projection.

There were softlights, spotlights, nine lights, nook lights, broads, tiled 1x1s and more. Some white, others color-variable. Most, with the exception of architectural floodlights, would also be showcased the following month in Las Vegas at NAB.

Prototype at Shadowstone of The Light Source’s flat 6-in. Fresnel LED light. Intriguing.

The photos accompanying this column highlight products at Shadowstone that impressed me. All of these companies have websites where their innovations can be examined in greater detail.

Were there any surprises left at NAB? You bet there were!

Fresnel LED lights were introduced by Litepanels and Gekko. This is a big development for two reasons. On the technical side, it signals the arrival of LEDs powerful enough to serve as single point sources for Fresnel lenses. On the production side, it means true focus and controlled-beam operation of LED instruments for the first time.

SolaENG, tiniest of three Litepanels Sola Fresnels at NAB. Draws 30W and outputs 250W tungsten equivalent. Two big rings at rear are for focusing and dimming.

Litepanels and other LED manufacturers have, in fact, discovered that paper-thin plastic Fresnel lenses akin to those long sold in Barnes & Noble as cheap close-up magnifiers can be used for LED beam control. (Which is why the lenses in front of Litepanels’ new Sola series Fresnels appear to lack concentric rings.) Litepanels and others, of course, have chosen better plastics, shapes, focal lengths.

Sola12 with 12-in. lens, largest Litepanel Fresnel at NAB. Consumes 250W, matches 2K tungsten, weighs 14 lbs. Smaller Sola6 sports a 6-in. lens.

(Nothing new: I used flat plastic Fresnels in the late 1990s with sources cool enough not to burn holes in them. I also experimented with low-wattage pinpoint sources behind 10-in. and larger Fresnel glass lenses. See photo below of K5600’s 24-in. lightweight Fresnel polymer lens, which thrilled me. Brilliant!)

Videssence tacked in a different direction, unveiling an innovative 100-watt LED spot, flat as a pancake, octagonal, about fifteen inches across. The lamp’s open face is divided into four quadrants, each containing nine high-intensity LEDs grouped in a square. The crowning innovation is that each of the four quadrants can be mechanically adjusted to toe in toward the light’s beam axis, creating a four-way concentrated overlap at long throws. Videssence says its ExceLED 100 has the punch of a 1K Fresnel. Testing it on the show floor, I’m inclined to agree.

Business end of a Litepanels Sola12. Focus and dimming are controlled by touchscreen. There’s also a focus crank. And remote DMX control. Did I mention no ballast?

Which brings us to the we-knew-it-was-coming department: since most LEDs are manufactured in China, guess who showed up to show off their own LED products? For the first time, five Chinese lighting and LED manufacturers set up a “Beijing Creates for the Worldâ€? trade stand in the Las Vegas Convention Center’s North Hall. Each company’s booth featured what at first glance appeared to be a Litepanels 1×1 but was instead a knock-off. There were also more compact square LED panels and what can only be described as 2x1s.

Gekko says its fixed-focus kezia 200W matches 1K tungsten. Beam angle is convertable to 20, 60 or 80 degrees by interchanging thin Fresnel lenses. Smaller 50W version was introduced too.

With the Chinese government pushing green technologies harder than our own, you can bank on explosive growth in Asian LED design and technology. Why build five power plants to burn incandescent lights when one will yield the same amount of LED illumination, if not more?

Interior of K5600′s lightweight Big Eye Fresnel. Its 24-in. molded plastic Fresnel lens certainly caught my eye. Same diameter as 18K HMI. All it lacks is a super-bright LED source!

To those who complain of dizzying change, I say we in film and video production have the best seats in the house in these “interesting times� (the purported Chinese curse). How can it not be exciting to participate in the evolution of solid-state lighting as it grows ubiquitous, gets lighter, cheaper, and more imaginative in design and utility?

Now you see it, now you don’t. Zylight demonstrates prototype of electrically controlled Active Diffusion, which they compare to Half 216 with 1/2 stop loss at maximum density. Subtle degrees of diffusion can be dialed in or varied during a shot.

A high CRI in the 90s would be nice, though…

Chinese LED lighting manufacturers sharing a stand for the first time at NAB will no doubt soon need their own larger booths.

Got that, Brightcast and Beijing Feiyashi Technology Development Co. Ltd.?