Photography has a 180-year history and women are a big part of it—not as subjects in front of the camera, but as visionaries behind it. For those who don’t already know this, a trip to the High Museum is in order. From the 19th century’s Anna Atkins, with her cyanotype photograms of seaweed, to the 21st century’s Mickalene Thomas, with her joyous mashups of Black liberation and classical iconography, “Underexposed” presents 100 photographs from the museum’s collection, images that chart the trajectory of female photographers and their influence—past, present, future. —E.C.