After successfully rebooting the Batman franchise with 2005’s “Batman Returns,” Nolan created a darker sequel, fueled by a truly terrifying performance from Heath Ledger, to even greater acclaim. More to the point, “The Dark Knight” has scored the best box office numbers of 2008. The soft-spoken British director, who made Super-8 home movies as a kid, has always loved pushing the technical limits of filmmaking. “Memento,” which he also scripted, began at the end of the story and ran backward; “The Prestige” was a tour-de-force thriller about magic and illusion. Appropriately, “Knight” is the first major feature film that used an Imax camera to shoot long sequences.