Weegee was among the first to fully realize the camera's unique power to capture split-second drama and exaggerated emotion. But his profound influence on other photographers, most famously on Diane Arbus, derives not only from his sensational subject matter and his use of the blinding, close-up flash, but also from his eagerness to photograph the city at all hours, at all levels: coffee shops at three in the morning, hot summer evenings in the tenements,...