ROCHESTER - As mainstream photography turns digital, the mammoth film-manufacturing hub that George Eastman opened here in 1891 is swiftly shrinking.

A decade ago, when it stretched across 1,600 acres, Kodak Park was easily the biggest industrial complex in the Northeast. By year-end, when Eastman Kodak Co. wraps up a drastic, four-year digital overhaul, its miles-long perimeter will encompass a mere 700 acres.

The factories where film, paper and other chemical-based products were made by generations of Kodakers are disappearing just as fast.

The company used explosives to implode three cavernous buildings this summer and has sold big tracts to developers, most recently a 330-acre plot anchored by a 2.1 million-square-foot warehouse.

Robert Burley, a photography professor at Ryerson University in Toronto, felt a tremor in his heart when Building 50 - a four-story paper products plant built in 1918 - was reduced in seconds to a pile of rubble on an overcast morning in mid-September.

“It's a very significant time in the history of photography, and the implosion of that building really made the point very strongly,” Burley said.

The transition to a world without film is occurring at lightning pace.

An estimated 67 percent of U.S. households had digital cameras in 2006, up from 20 percent in 2002, according to market research group InfoTrends.

Even as revenues in its traditional businesses tumble, Kodak is still leaning hard on high-margin film to generate the profits needed to see it through the most painful passage in its 126-year history.

Kodak Park, now a mix of old-world chemical plants and the most advanced filmmaking technology anywhere, sprouted up on an abandoned fruit farm a few miles north of downtown two years after Eastman launched silver-halide film in 1889. More than 200,000 employees have passed through its gates.

Only about 100 buildings will be left this winter, down from 212 in the 1990s. Kodak's work force also is contracting: its global payroll will soon slide to 34,000, half what it was five years ago. In Rochester, there will be fewer than 10,000 employees - versus 60,400 in 1983.

Kodak's “shrinking structural presence” has raised fears among residents that “perhaps we're not on a track to success” and that Kodak might even relocate its headquarters elsewhere, Mayor Robert Duffy said.

Yet despite the turmoil in the photography industry, “I don't get discouraged,” he said. “If they can get on a path to the future, and I know they can, it's going to benefit Rochester.”

The shift to digital is irreversible now - Kodak's digital research operations are based at Kodak Park - but Burley thinks Kodak “wasn't changing fast enough” before the arrival in 2003 of its current chief executive, Antonio Perez.

“I think Perez realizes that the company does have a lot to offer and can be successful in this new electronic system of image-making,” Burley said. “But dramatic changes are required, and required quickly.”