The Rodenstock APO-Sironar N 100mm f/5.6 is a compact normal-to-wide large format lens with a 151mm image circle and 72-degree coverage. At just 170g with a 40.5mm filter thread, it is one of the lightest lenses for large format photography. The N designation indicates Rodenstock's standard APO-Sironar line with apochromatic correction. It covers 6x12cm format with movements and is popular for lightweight travel kits.