Two Chicago-area businesses played important behind-the-scenes roles in the installation of the Cyrus Tang Hall of China exhibit at Chicago’s Field Museum. IMARK member Paramont EO, Woodridge, Illinois, teamed
up with Lightswitch Architectural, a lighting and visual design firm with offices in Chicago and throughout the country, to provide an LED-based lighting system for the exhibit. The Cyrus Tang Hall of China exhibition is the nation’s only major permanent museum installation focusing on 5,000 years of Chinese history and culture. The 6,000-square-foot exhibit required specialized lighting design and equipment to minimize light degradation of the 350 objects displayed and to support the visitor experience, according to Alvaro Amat, exhibition design director at the Field Museum.

In addition to being extremely energy efficient and having a lifecycle several times that of conventional light sources, a major reason for LED’s growing popularity in museums is that LED emits no artifact-degrading ultraviolet (UV) light. “Museum exhibitions must be responsive to a broad age range of viewers—including those with limited or poor vision due to age or other impediments—but also to protect the often delicate nature of the objects displayed,” Amat explained.

“For instance, many of the artifacts displayed can be affected by UV light or visible daylight in certain wavelengths and intensities. The impact of UV can range from fading of colors and pigments to cracking and irreversible decomposition of more fragile and priceless materials,” he said. Thatcher Waller, senior lighting designer at Lightswitch Architectural, said the majority of the fixtures lighting the exhibition are solid-state LEDs. “The recent advances in LED lighting technology have made our job easier because of the quality of light we can achieve that we couldn’t before,” Waller said. “LED addresses our two biggest problems with incandescent lighting, which were color temperature and UV. With LED, we can achieve better color rendering on the artifacts and LED’s lack of UV means there is minimal light degradation to the objects displayed.”

The recent upgrade to LEDs to illuminate Michelangelo’s masterpiece on the ceiling of the Sistine Chapel is just one of the latest in a series of high-profile installations that show how far LED technology has come in museum and high-profile art applications—not only in terms of its acceptance and adoption, but also in terms of its performance.

A recent study of LED use in museums by the U.S. Department of Energy found that 40 percent of museums now identify LED as their principal lighting type—compared to almost none in a similar 2009 study. For Waller, the exhibition’s challenges went beyond ensuring that the type of lighting selected and the amount of light on objects didn’t negatively impact the artifacts.

“Our biggest challenge was enhancing the visitor experience by allowing them to see the artifacts as they were originally seen when they weren’t artifacts,” Waller said. “Many of the objects in the exhibition would have been mostly seen in daylight. For example, the Spirit Stones on display in the East Garden at the end of the exhibition would have originally been experienced outside in a garden, so we created that type of light.”

Another challenge of this particular project was balancing the display case lighting with the light from the reading rails that stretch the length of the cases and the touchscreens that are in front of them. To allow the artifacts to be seen as they were intended to be seen, Lightswitch replicated daylight conditions using white, 3,000 Kelvin (K), LED lighting. “We balanced the three types of light—case lighting, reading rail backlighting and light from the touch screens—by controlling the amount of light on or emanating from each surface and
ensuring that they were all evenly illuminated,” Waller explained. “We did that with prototypes and mockups and by working with the touchscreen fabricators to make sure that the light matched the case lighting.”

“In addition to procuring all the exhibition lighting components, Paramont EO double-checked the custom fixture measurements, color temperatures, beam shapes and sizes to ensure the supplied equipment performed as envisioned,” said Scott Shellberg, director of lighting design and applications at Paramont EO, a company that was named a “Showroom of the Year Finalist” by Residential Lighting. “Lighting helps us create atmospheres for the different kinds of spaces that guide the visitor experience and drive the overall narrative of the exhibition,” Amat said. “The Cyrus Tang Hall of China required a calm atmosphere, a feeling of respect and contemplation, peace and harmony, plus even and soft lighting for the multitude of objects presented.”

“To accommodate the diverse variety of objects and artifacts on display, the light levels in the display cases vary,” Waller continued. “Some sensitive artifacts, such as paper and fabric, required five foot-candles (fc) or less of light and others, like stone, were illuminated with up to 20 fc of light.” Lightswitch employees coordinated with the museum staff to determine in advance the final object placements, so that the designers could map out the lighting accordingly. Then they designed case lighting that is broken up into sections that can be tuned using the control system to provide the proper light levels for each type of object when the viewer approaches.

“The recessed fixtures were selected for their quality of light output and flexibility for focusing,” he said. “For the slate walls, we used IO graze fixtures because of the light output. The lighting is controlled by an electronic theater control (ETC) paradigm that provides 0-10 volts and traditional phase dimming.”A lot can get lost in translation between the vision and the end result,” Shellberg explained. “Paramont EO’s attention to detail and knowledge of LEDs ensured the designer’s vision was realized and achieved the desired effect.”

“As lighting designers, we look at the reliability and track record of our lighting supplier, as well as the capacity to deliver and respond to our specific needs,” Waller said. “Paramont EO not only fulfilled these requirements, it was able to provide a wide range of very specific lighting equipment solutions, taking special care to deliver the best product fit for each part of the project.”