In 1938, Penn bought a Rolleiflex with earnings from drawings published in Harper's Bazaar, using it to record his observations in what he called "camera-notes." These images reveal an interest in vernacular signage and painting that continued to animate Penn during the Second World War, in Europe and India. In addition to photographing "the lulls, the lags, the quiet interims and backwaters of war," he used his camera to collect examples of political graffiti, traces of resistance and occupation.