If you are allergic to big, pretty pictures, stay away from Julie Blackmon’s photographs. But their glossy surfaces coat shadowy domestic setups: children out of control or with too much control, surrounded by a level of household wealth that promises bright order and results in light horror. Blackmon is a Missouri mom of three and the eldest of nine children; she emerged as a photographer around a decade ago. Her last solo show at G. Gibson Gallery was six years ago. Undertow is all new work. (G. Gibson Gallery, 300 S Washington St, ggibsongallery.com, by appointment, free, through July 13)