Inventor Tim Jenison, a designer of post-production equipment for film and TV (he did Video Toaster), is not an artist. But he wants to know how Johannes Vermeer, back in the 1600s, created his photo-realistic paintings. He produces his best guess: a mirror on an arm, reflecting the source material in tiny chunks, so the painter is able to meticulously reproduce on canvas. Is it art or is it mechanics? Tim’s Vermeer suffers from two problems: the production quality varies wildly in composition and grade, from the PBS-like talking heads to the ratty home video portions. The other is producer/narrator Penn Jillette (Teller directs), who is not content to be merely dictating the action but also needs to be part of it. But the doc is worth a look for Jenison himself—a calm, engaging presence whose success you root for—and for its back half, which shows the process he goes through to recreate the setting of Vermeer’s “The Music Lesson”—at one point he chops his own lathe in half—to say nothing of the actual four-month painting process, which recalls, stroke by stroke, the question of why we make art in the first place.