The web of intimacy and influence that connected Tina Modotti and her teacher, mentor, and lover Edward Weston was most apparent during the years they spent in Mexico. From 1923 to 1926, when Weston returned to California and Modotti, already passionately involved in the country’s radical politics, joined the Mexican Communist Party, the couple engaged in a vigorous creative exchange that affected both their careers. The results of that exchange can be seen in this remarkable show, which gives slightly more space to Modotti, whose work tends to overshadow Weston’s emotionally and challenge it to rise to the political occasion. Weston’s photos, including a variation on his famous pepper and a voluptuous Modotti nude, are models of modernist restraint—brilliantly composed but a bit chilly. Modotti could be just as severe: Her fine-tuned study of telegraph wires proves she learned Weston’s lessons well. But her roses are impossibly lush, and she doesn’t suppress her revolutionary fire. A photo of her post-Weston lover, Cuban radical Julio Antonio Mella, sleeping bare-chested on the grass, is erotic, tender, and artful in a style utterly her own.