ONE SUMMER AFTERNOON IN PÈRE LACHAISE, the sprawling cemetery in the east of Paris, a white-haired man, neatly dressed, was tending his own grave. First, he brushed away a spider web that had formed in a corner of his chapel, a small box-like structure that he had chosen as his place of rest. He then swept the slabs that, in time, will be lifted to allow his coffin and that of his wife, Anne, to be lowered into the earth. On a stone shelf was a large camera, sculpted from black granite, its “lens” so polished that the man, a photographer named André Chabot, could be seen in reflection. Finally, he stooped—not without effort—to lift a few strips of film brought as offerings by tourists, then wound these around the…