The San Francisco International Film Festival launched its 50th anniversary edition Thursday night in apt style.The oldest extant such event in the Western Hemisphere opened with a movie at the city’s last remaining art-deco movie palace, the 1922 Castro Theatre, then moved over for a party at the near-palatial City Hall, built in 1915 to replace the one destroyed in the ’06 quake. Putting art before glitz, at least for two hours, was opening night selection “The Golden Door,” a forthcoming Miramax release and French-Italian coprod about Sicilian immigrants to the U.S. a century ago. As Exec Director Graham Leggat noted beforehand, SFIFF is sole fest to have programmed all three pics to date by Italo helmer Emanuele Crialese, who showed up to introduce it alongside his recurrent star Vincenzo Amato. Native Roman Crialese, who studied film at NYU, joked that his own path had an Atlantic-crossing element: “If I’d stayed in Italy and didn’t emigrate to the U.S., I would certainly be a lawyer.” While some viewers remarked pic seemed a tad long, slow and abstract for an opener, it nonetheless served notice that fest remains willing to make challenging choices even for its “Big Nights.” Though latter to come will be considerably starrier, with tributes to Spike Lee on Wednesday and Robin Williams the following Friday. This Sunday’s docu preem “Fog City Mavericks” is expected to lure Bay Area-residing luminaries George Lucas, Williams, Philip Kaufman, Carroll Ballard, Brad Bird, Christopher Columbus, Walter Murch, Saul Zaentz and others for post-screening Q&A at the Castro. Calling the fest he’s headed since late ’05 “the flagship international film festival of the Americas,” Leggat paid tribute to those “founding figures, our colossi” who’d preceded him — founder Irving Levin, subsequent E.D. Claude Jarman, longtime artistic director (now at Tribeca) Peter Scarlet, and still-active Board prez George Gund III, an unpopular, shortlived A.D. between Scarlet and Leggat was obliquely referenced in his mention of recent “lean years” SFIFF is now bouncing back from. Notable attendees for the night included AMPAS president Sid and producer spouse Nancy Ganis; Peter Coyote and S.F. Film Commission head Stephanie Coyote; former mayor Willie Brown; thesp Delroy Lindo; and famed local documentarian Les Blank.