 Marvel put the project in production as its first self-financed film, with Paramount Pictures distributing.Favreau signed on as director in April 2006, and faced opposition from Marvel when trying to cast Downey in the title role; the actor was signed in September.Filming took place from March to June 2007, primarily in California to differentiate the film from numerous other superhero stories that are set in New York City-esque environments.