Art Ginsburg, founder of Art’s Deli in Studio City, died Wednesday. He was 78. Art’s Deli served as a gathering place for some of the film and television elite in its early days. Today, industry veterans such as MTM Productions old-timer Abby Singer and Paul Thomas Anderson, director of such blockbusters as “Boogie Nights” and “There Will Be Blood,” can still be found at the deli. Ginsburg handed off daily operations of the deli, which opened on Ventura Boulevard in 1957, to his children in 2010. His son, Harold Ginsburg, has been managing the Valley landmark since. The deli has announced that it will close Friday to observe a day of mourning for its founder.