Let There Be Light Emitting Diodes: How to Illuminate the Sistine Chapel

With the help of strategically placed fixtures, Michelangelo's work is getting some mood lighting.

When Michelangelo painted the ceiling of the Sistine Chapel, he did so, for the most part, using the light of the sun that streamed through the windows of the building. And for the past 500 years since then, viewers have admired the results of that work, for the most part, with the help of that same light source. It wasn’t until the 1980s that, concerned about solar radiation damaging the frescos' paint, Vatican officials blocked off the chapel's windows. In their place they installed a system of halogen light bulbs that emitted pigment-preserving, low-energy light.

That switch, however, has made viewing the Sistine Chapel something of a difficulty for visitors. The chapel's ceiling is 6,135 square feet in area; viewers observe its expanse from the ground. All the details Michelangelo included in his fresco—arms lifted, fingers stretched—tend, from that distance, to blur and fade.

Enter light. Another kind of light.

Next month, the Wall Street Journal reports, the famous ceiling will be getting a new look in the form of new lights. Some 7,000 LEDs, to be precise—with fixtures that will be studded around the perimeter of the chapel. The German lighting manufacturer Osram, which is providing the lights to the Vatican, custom-designed an illumination system for the Sistine project—one that involves dozens of miniature tripods, anchored into the crevices of the ledge that runs around the chapel walls.

One of the challenges Osram’s designers faced was that fact that, when you’re lighting a ceiling like the Sistine’s, you’re not just looking for uniformity. You’re also looking to create an environment that will best allow visitors to appreciate the colors and details of the ceiling’s art. Michelangelo adjusted his work to account for the shape of his architectural canvas; the lighting designers of 2014 needed to do the same. Osram technicians analyzed 280 patches on both the chapel's ceiling and its wall frescos, creating a spectrum map of the colors Michelangelo used in decorating the Sistine’s surfaces. From there, they designed an interactive system of LEDs that blend red, blue, green, and white shades of light—each combination meant to optimize the display of the frescos.

More technically, as LEDs Magazine explains it,

The new lighting will be aimed precisely in the same direction as the natural light with the fixtures hidden below windows. The SSL project will ensure uniform lighting with no glare, although illuminance levels will rise to 50 to 100 lx—a level typical of museum lighting of artwork. That level will provide a much better viewing experience while still minimizing degradation of the work, especially since LEDs don't emit energy in the UV band.

The Roman chapel, the Journal notes, isn’t the first artistic venue to experiment with illuminatory improvement. Last year, courtesy of Toshiba, Paris's Louvre Museum got some LEDs to light, among other works, the Mona Lisa. Also making the LED switch: London's National Portrait Gallery, Amsterdam's Rijksmuseum, and Boston's Museum of Fine Arts.

Museum designers say that the LEDs—which have been stress-tested to ensure that they don't fade paintings' pigments—don't just allow for more visual clarity in the viewing experience. They also have a more pragmatic benefit: LEDs have a longer life than traditional halogen bulbs. Which means that the museums housing nearly priceless works of art can worry a little less often about doing one of the most basic jobs there is: changing the light bulbs.