Comcast Corp. unveiled to employees yesterday a 15-minute Christmas show on the superbig video wall in its Center City headquarters lobby, which is open to the public.

The video was created and edited by David Niles, who modernized the Christmas show at New York's Radio City Music Hall in the mid-1990s. The Comcast show contains a 90-second Nutcracker, a vertiginous computer-enhanced view of a Santa flying his sleigh into lights-aglow Philadelphia, and winter-dressed dancers on the Art Museum steps.

The video opens to the public at 10 a.m. Thanksgiving and will show daily on the hour through New Year's at the Comcast Center, 17th and Arch Streets. The last show each day will begin at 8 p.m.

The specs for the video wall are impressive: The screen is 83 feet wide and 25 feet high. Comcast calls it the world's largest four-millimeter LED screen, with 10 million pixels. The screen is five times brighter than the latest high-definition TV.

Comcast and Liberty Property Trust, which built the new Comcast Center, are seeking to attract city visitors and downtown workers to the office complex, which includes retail shops and restaurants. A person can enter the Comcast lobby through Suburban Station.

Brian L. Roberts, chief executive officer, said the video was a 21st-century version of a holiday show, a complement to the traditional holiday light show at the Center City Macy's, a few blocks away. The Macy's light show was first shown in the 1950s.

Ray Biswanger, executive director of the Friends of the Wanamaker Organ, said Macy's had modernized the light show with energy-efficient lights and had brought back the "magic Christmas tree."

"I'm hoping that we're so close to each other that it will be fun," Comcast's Roberts said. "The organ and what it represents is fantastic."

Comcast says it will collect toys and books for needy children in its lobby during the holiday season.

Contact staff writer Bob Fernandez at 215-854-5897 or