Making Things Brighter

Photo: Elle Starkman, PPPL

PPPL's Eliot Feibush at the Lab's upgraded Visualization Wall.

The colors are brighter, and the images are sharper on the upgraded Visualization Wall, a high-resolution, rear-projection system at PPPL.

That's just part of the recent work of PPPL computational scientist and software developer Eliot Feibush, who, within the past year, has had a hand in improving two visual-projection systems at PPPL and creating Princeton University’s largest-ever visualization display wall.

"I tried to keep building off the lessons of each one," said Feibush, who has been part of PPPL’s Computational Plasma Physics Group and worked on the Lab's Visualization Wall since November 2001.

PPPL Visualization Wall

PPPL's wall project began in 2000 based on a multi-projector design developed by the University's Computer Science Department in 1998. It used 12 projectors to discern eight million pixels, but the images appeared tiled. The projectors varied in brightness and color, and drifted out of alignment.

"We had been stewarding the world's oldest display wall," said Feibush. "It was time to find an upgrade path."

By 2009, PPPL Media Services Head Carl Scimeca provided a spare auditorium projector to replace the multi-projector display. But there were still some problems with the plastic screen, which had permanently warped, causing images to be out of focus. The old screen also transmitted only 40 percent of the projector's light intensity, absorbing the rest.

Feibush knew from working on the University display wall that a translucent vinyl screen could stretch flat for a completely focused image. In June, PPPL's Larry Jones and Ray Whitley installed a new screen that now transmits 75 percent of the light. The change has enhanced the brightness and contrast of the display.

"There's a lot of detail that we never saw before," Feibush said.

The recently installed system will allow for finer experimental data and simulation visualization. It is well suited for smaller audiences that do not require the Lab's auditorium. Scimeca also installed audio-video conferencing capabilities earlier this year.

The wall's upgrade goal includes eventually restoring the resolution to eight million pixels via four high-definition projectors, which now cost a sixth of the original 12 projectors.

Photo: Elle Starkman, PPPL

PPPL's Eliot Feibush at the PICSciE display wall at Princeton University's Lewis Library.

University Display Wall

Knowing the troubles of multi-projector displays, Feibush advocated for a single-projector system for the University's new rear-screen display. Based on a digital cinema projector, he designed a seamless display wall with eight million pixels. Light from the projector reflects off an angled mirror to fill the 9-by-17 foot fabric screen. The Princeton Institute for Computational Science and Engineering (PICSciE) in the Lewis Library began using the display in December.

Researchers are generating scientific visualizations, where users see and work with large amounts of data, simulations, graphs, images, or videos. The system has been used for visualizing astrophysical and geospatial data — data that have a geographic context. The first round of judging for the University's annual "Art of Science" competition in May took place on the wall. A group designing a new computer center uses the display weekly instead of rolling out blueprints. Feibush expects others will find more uses for the system.

"I've been doing computer graphics for over 30 years, and this is the best display I've ever seen," Feibush said of the PICSciE system. "In 1977 the only graphics you could find were in a few research labs. Now people carry a million pixels in their pocket. Today only a few universities have a high-resolution display wall. I'm eager to see some creative new applications."

NSTX Control Room Wall

A different creativity improved the three-projector display in the control room of PPPL's National Spherical Torus Experiment (NSTX). The display colors were faded and distorted because constant use of the projectors had scorched the polarizers, the plastic films in front of their light bulbs. Rather than replace the expensive projectors, Feibush negotiated with the manufacturer for a cost-effective replacement of the polarizers. Over a period of four months, each projector was sent to the manufacturer, while the other two remained in the control room. Finally, all of them have been reinstalled and calibrated by the NSTX Controls and Data Acquisition Group to recreate the three-projector display.

Feibush said improving the quality of all three display walls has been a successful ongoing collaboration between PPPL and the University.

"Princeton's computer science research fostered our Lab's Visualization Wall, which, in turn, led to the NSTX control room display," he said. "We contributed our expertise to the PICSciE display wall, and then we applied that experience to our own upgrade."