Copal 0, Image circle at 1: infinite =262mm Apo-Sironar-N The Apo-Sironar-N is the all-round lens for the professional photographer. Typical applications are product shots of every kind, industrial subjects, landscape and city photography. The Apo-Sironar-N equally provides an ideal longer focus lens with smaller formats. Monorail view cameras permit almost unlimited extension (especially with extension bellows). As a result optically problematic tele lens designs whose Barlow group tends to produce color fringes are no longer needed; their short back focal length only provides advantages for cameras without a bellows for focusing. The six-element Apo-Sironar-N bears the “Apo” designation without restriction despite its very advantageous price. The field angle is 72°. The image circle diameter exceeds the diagonal of the recommended format by around 45%; this gives the photographer considerable edge quality together with abundant shift and swing or tilt possibilities.