Kirsten Johnson assembled this impressionistic memoir from footage she shot over 25 years as a documentary cinematographer, working for such filmmakers as Michael Moore, Laura Poitras, Gini Reticker, Amy Ziering, and Kirby Dick. At one point Johnson’s producers assembled a “trauma cut” that highlighted all the horrible and hair-raising things she’d witnessed, but the finished version is more mercurial, focusing on odd moments that, as Johnson explains in an opening title, “have marked me and leave me wondering still.” A prosecutor in Jasper, Texas, presents physical evidence in the trial of three white men who chained a black man to their truck and dragged him to his death; philosopher Jacques Derrida notes the camera following him around on the street and jokes that he’s a true American now; a young black woman, represented onscreen only by her restless hands in her lap, explains why she’s about to get an abortion and ultimately bursts into tears. Personal footage of Johnson’s family and friends, woven into the documentary scenes, enhances the sense that any life is a series of amazements.