By BROOKS BARNES

LOS ANGELES - The imminent return to three-dimensional filmmaking is in danger of becoming Hollywood’s latest flop. Some of the mightiest forces in film - Jeffrey Katzenberg, James Cameron, John Lasseter - think the masses will soon demand that all movies be shown in newly available digital 3-D. Mr. Katzenberg, in particular, has pushed the format, traveling the globe to herald the technology as a transformative moment for cinema akin to the introduction of sound.


He has plenty of fellow believers, at least in Hollywood. The Walt Disney Company alone has 15 three-dimensional movies in development. Twentieth Century Fox is betting an estimated $200 million on “Avatar,”a 3-D space adventure directed by Mr. Cameron and set for December release, his first nondocumentary film since 1997’s“Titanic.”All told, the movie factory has over 30 3-D pictures on the way.


But analysts are starting to warn that all of that product could find itself with no place to go. Studios, thrilled by 3-D’s dual promises of higher profits and artistic advancement, have aggressively embraced the technology without waiting for movie theaters to get on board. And without those expensive upgrades to projection equipment at the multiplex, mass market 3-D releases are not tenable.


“It’s starting to look like there will be a lot of disappointed producers unable to realize the upside of these 3-D investments,”said Harold L.Vogel, a media analyst and the author of“Entertainment Industry Economics.”Filming in 3-D adds about $15 million to production costs, he said, but can send profit soaring because of premium ticket pricing.


Only about 1,300 of North America’s 40,000 or so movie screens support digital 3-D, along with 250 large-screen Imax theaters. Abroad, where films now generate up to 70 percent of their theatrical revenue, only a few hundred theaters can support the technology. It costs about $100,000 for each full upgrade.


Studios require about 3,000 screens in North America for most new releases. Big-budget movies like “Avatar”or“Monsters vs. Aliens,”a 3-D entry from DreamWorks Animation, typically open on more than 4,000 screens.


“The crunch has everybody scrambling,”said Chuck Viane, president for domestic distribution for Walt Disney Studios.“We had expected many more screens to be available by now, no doubt about it.”


Upgrades have lagged primarily because of industry infighting over who will pay the cost. Studios expected theaters to take the lead because digital equipment would allow them to raise prices - tickets to the new crop of 3-D movies run as high as $25 each . Exhibitors, hurt by soaring real estate costs, wanted studios to pay.


Movie chains and four of the six major studios agreed in September on a plan to convert more than 15,000 theaters. But the financing plan came together just as the credit markets froze.


Studios and exhibitors say the upgrade plan is not in jeopardy.“This is a long-term commitment and a long-term strategy,”Mr.Katzenberg, the chief of DreamWorks, said recently.


People who remember 3-D from the 1950s associate it with low-budget films ,stiff cardboard glasses and jerky, stomachturning camera movements.


This time, movie executives insist that everything has changed. Digital projectors deliver the images with perfect precision - eliminating headaches and nausea - while plastic glasses have replaced the cardboard.


Most important, say filmmakers, new equipment allows movies to be built in 3-D from the start, providing a more immersive and realistic viewing experience and not one based just on visual gimmicks.