MINNEAPOLIS – For much of the 20th century, going to the movies meant walking to a single-screen neighborhood theater, where the light from a projector passed through strips of celluloid. Jeffrey Eisentraut loved that experience so much when he was growing up that he eventually moved to Southern Illinois to run three historic theaters: the Orpheum in Hillsboro, the Canna in Gillespie and the Roseland in Pana. But now Eisentraut and other independent operators are under siege.

The villain is technology. The movie studios are rapidly replacing traditional reels of celluloid film with hard drives that are cheaper for them to ship and compatible with lucrative 3-D technology. Hollywood says that the digital conversion will benefit moviegoers with consistently bright images and state-of-the-art sound. But in the next few months, exhibitors who don’t purchase expensive new digital projectors may be forced out of business.

Since the first flicker of a nickelodeon, movie-theater owners have invested in many upgrades, from stereo sound to stadium seating, even while losing large portions of their audience to television, home video and the Internet. But the cost of the digital conversion is unprecedented: about $50,000 per auditorium.