Fifteen minutes may not seem very long for a title character to appear in a movie, but according to Sirius Black portrayer Gary Oldman in an interview appearing in the latest issue of The Book LA, that's about how long he'll actually appear in Harry Potter and the Prisoner of Azkaban.
Q: Aren't you the title character?
A: Yes, I am the title character, but in the book, as in film, one awaits the arrival of Sirius Black... There's a big buildup. It was anywhere between 12 and 15 days of shooting, spread out. Harry Potter is a 4 to 6 hour shooting day, but that is spread out over 12, because the children have to be tutored and fed and rested, and the animals of course - Scabbers the rat gets a break every 15 minutes.
Q: Does that make it hard or easier to act?
A: It makes it a little harder to keep a focus, a continuity, or a level of emotion and energy. But when you take on a movie that involves children and animals and special effects, it's a process that you just have to surrender to. It's time consuming, and it 's slow, and it can be bone-crushingly boring, until those moments when you're actually in the moment doing it. But the three main kids, Rupert (Grint), Emma (Watson) and Daniel (Radcliffe), are focused and professional and unspoiled, not remotely precocious or pretentious. They are just down to earth, really nice kids. And I adore Dan, who plays Harry. He is the coolest coolest kid.