Once Richard Heene admitted in court that he wrongly sent authorities on a wild goose chase across Colorado to save the son he thought was aloft in a runaway balloon, friends and supporters seemed to take off just about as fast as that balloon. All except for one: Steven C. Barber, a 48-year-old filmmaker who says he still believes Heene really thought his son was in the balloon as it spun wildly through the skies on Oct. 15. He plans to prove it, Barber says, when he releases the documentary “Balloon Boy: Guilty Until Proven Innocent” later this year. Barber has known Heene for more than 10 years and says he has dozens of hours of film of the backyard inventor pursuing one science project after another. He compiled much of that footage, the filmmaker says, in an effort to help Heene land a TV reality show chronicling his science adventures. What Heene was trying to do with the balloon, Barber says, was solve the world's traffic problems by creating a cheap, lighter-than-air vehicle that would allow people to float over congested freeways. Although the idea may sound far-fetched to some, even ridiculous to others, Barber says, Heene is a “mad genius” with a penchant for exploring offbeat scientific theories. He's willing to show only one brief snippet of film, however, taken before the launch, when the balloon was still in pieces on the floor of Heene's Fort Collins, Colo., home and he was explaining how he planned to put it together. Barber said he filmed that segment for one of the many TV show pitches he helped put together for Heene over the years. Barber, whose previous films include the World War II-era documentary “Return to Tarawa: The Leon Cooper Story,” acknowledges he is announcing his plans for “Balloon Boy” just as he is beginning to promote another movie. His documentary, “Unbeaten,” on a 267-mile (430-kilometer) wheelchair race through Alaska, is in theaters this week in an effort to get consideration for an Oscar at the 2011 Academy Awards.