The first Friday of each month, the Cleveland Museum of Art hosts its popular Mix at CMA event. The museum stays open later than normal for the occasion, which features dance, drink and a theme-based program. Tonight's event celebrates the new exhibit Proof: Photography in the Era of the Contact Sheet.; it also offers attendees a chance to hear the sweet and/or scandalous love stories behind some of the art in the museum's permanent collection. Tickets are $10 in advance, or $15 at the door. CMA members get in for free. The party runs from 6 to 10 p.m. (Niesel)