Artists wary as solid-state lighting replaces tungsten
In May, a panel representing all facets of the art of filmmaking — including cinematographers, art directors, makeup artists — gathered at the Motion Picture Academy’s Pickford Center in Hollywood to view the results of a test. A model wearing a specifically designed dress with various gradations of blue and blue-green had been filmed while she was lit by the latest addition to the cinema lighting family — the LED fixture.
The results were shocking. They didn’t represent at all what everyone present had seen on set when the dress was photographed.
“Now, it was simply a nice blue dress,” says visual effects specialist Jonathan Erland, who chairs the Solid State Light and Research subcommittees of the Academy’s Science and Technology Council. “The subtle differences in the colors were gone. And in movies, subtle is the difference between excellent and not so excellent.”
The experience is not a unique one, as cinematographers, eager to put the LED technology to work on their sets, come up with less-than-acceptable results. “There have been color-rendering problems,” says SciTech Council director Andrew Maltz. “The colors that appear on film or digital cameras are not what the d.p.’s expect. When they used these new devices, to their eye, it looked fine, but the recorded image was wrong.”
But whether d.p.’s like it or not, solid state lighting is coming.
By 2014, the Energy Independence and Security Act of 2007, signed into law by President Bush, requires that household light bulbs in the range of 40 to 150 watts be made to meet certain energy requirements — which tungsten doesn’t. So adios tungsten.
Of course, studio lights are far brighter than 150 watts. But by the time 2014 rolls around, directors of photography won’t have a lot of choices, as manufacturers phase out production of tungsten lamps. There either won’t be any to buy or they’ll be prohibitively expensive. And they don’t mix well with whatever will now be stuck in all those practical lights on sets — table lamps, etc. (i.e. compact fluorescents and the like). “I call that ‘chromatic chaos,'” says Erland.
In the world of cinema lighting, there are essentially only two sources — tungsten and daylight.
“Fifty years from now, we probably won’t have any tungsten lights, but hopefully we’ll still have daylight,” jokes cinematographer Daryn Okada, a SciTech Council member who’s also been working on the Academy’s study.
So to fill the void left by the impending disappearance of tungsten lights, manufacturers, over the past few years, have been trying to find a suitable replacement, and have essentially settled on one: the LED. But, as described above, many d.p.’s are finding it far from “just like tungsten.”
Okada discovered this firsthand on a project he was shooting three years ago, when he employed an LED light to augment the tungsten fixtures he had on the rest of the set. “The manufacturer claimed it to be a ‘tungsten’ LED source,” he recalls.
Though the light from the LED appeared tungsten-y on set, when Okada viewed dailies of the footage, he got a nasty surprise: “Her face was totally cyan,” that un-skinlike color between blue and green. The image also could not be repaired in post — there simply wasn’t enough of the right color of light on the film for a color timer to bring out. “That’s when I knew we had to look into this. I didn’t want it to happen to anyone else. Though manufacturers like to suggest, ‘Abandon everything else, you can just switch over to this,’ that was not the case.”
Such lighting providers as Mole-Richardson, Arri, PRG Lighting, Gekko and LitePanels have been working hard trying to make something that simulates tungsten, but with limited success.
That’s where the Academy comes in. “We’re dealing with an industry and an art that has had been dominated by one source — tungsten — for years,” Erland says. “Our goal is to encourage the development of lights that simulate tungsten.”
But, adds Okada, “We want to make sure that they don’t end up like the way street lights were when they switched from tungsten bulbs to sodium vapor, where everything was so blue you couldn’t see what color anything was.”
Most of us know LEDs these days from the cheesy flashlights from Home Depot that emit light much like those street lights Okada mentions — they’re blue, and it’s hard to see anything. Those are the low end of the LED world. Lighting manufacturers get better quality LEDs that are called “white” — though not quite.
“If it’s the only light on in the room, it looks white, because your eye adapts,” says Kodak Entertainment Imaging’s Gary Einhaus. “It looks white to your eye, because you don’t have any other point of reference to compare it to. But therein lies the problem with LEDs. Your eye adapts to them, but to film or a digital camera sensor, it doesn’t necessarily look white.”
Adds Erland: “Our brains have a built-in color corrector that makes everything OK. Film does not. The response is not only different in film, but from one film stock to another and from film stock to a digital camera.”
One might expect that lighting manufacturers would be turning to film stock makers like Kodak and telling them, “These are the de facto lights now — make your film match what’s coming out of our lights,” which, in effect, is what happened when tungsten film first showed up — thus, “tungsten-balanced film.”
But it’s not so simple with LED light fixtures — they’re all different.
“The problem is, there’s no standard,” says Einhaus. “It’s a moving target.”
Some manufacturers, such as Mole, have gone the route of working with an LED supplier, Osram, to develop a white LED that leans a lot closer toward the real tungsten look than most. To the point, even, that some d.p.’s are comfortable using them regularly as primary light sources.
“We used the Mole LEDs on ‘Captain America,’ and they performed as designed and required no gelling to get them to harmonize with natural tungsten and daylight sources on the set,” says cinematographer Shelly Johnson.
Other companies, like Arri and Gekko, are focusing on so-called “multi-emitter” lights — fixtures that have other color LEDs besides white, in an attempt to better replicate light that looks like tungsten.
“They’re available either with a fixed output, at either tungsten or daylight, or variable in between,” by way of a tunable adjustment, says Arri’s VP of Lighting Products John Gresch.
Johnson has used tunable LED fixtures, primarily with digital cameras, which permit him to see on a monitor how the image is turning out before committing to the image and that turned out to be a good idea.
“We had one set where we were using the tunable LEDs and wanted to accomplish a soft pale blue wash on a wall. I mixed the LEDs by eye, and when we got them on camera, instead of being a pale blue, they were a saturated purple. So I went the opposite direction and balanced the color mixing of the light through the camera until I saw the color value I wanted through the lens,” which, to the eye, was a Kelly green. “None of that green photographed, but was visible on set.” It was nonetheless a shock to the set’s designer. “I showed him the way it looked on the monitor, and his heart rate returned to normal.”
For Johnson, it’s a matter of getting used to what’s showing up on set. “LEDs are simply a new technology that a cinemato-grapher has to do his homework with in order to get these lights to function to their full potential.”
The Academy will, of course, continue to study LED and other types of sources as they appear on the market. “We’re now seeing an evolution of the design of the lights,” says Einhaus. “With the improvements we’ve seen, from early to current, and how much it’s improved, suggests to me they’re certainly moving in the right direction.
Adds Erland, “The introduction of any new technology like this is going to be a bumpy ride. And we’re trying to smooth it as best we can.”