The Watermill Center is presenting a weekend of screenings starting tomorrow at 4:15 p.m., when the Hamptons International Film Festival will show Katharina Otto-Bernstein’s “Absolute Wilson,” a portrait of the center’s founder and artistic director, Robert Wilson, at the East Hampton Cinema. The film will be screened again, at 4 on Saturday, at the center itself, where it will be followed by a conversation between the filmmaker and Dr. Frank Hentschker, executive director of the City University’s Martin E. Segal Theatre Center in Manhattan.