In 1956, two years after the introduction of the Nikon S2, Nikon delivered a stunning new 35mm (3.5cm) lens of 7 element 5 group design with a maximum aperture of 1:1.8.  It employed rare earth Lanthanum glass to improve spherical aberration and curvature of field, enhancing both sharpness and image flatness. This Nikon mount lens used a convex shaped rear lens element larger than the front, which minimized the spherical aberration and coma problems usually associated with fast wide angle optics. It was one in a series of excellent fast optics produced by Nikon for their rangefinders, following the 8.5cm 1;1.5 in 1953 and the 5.0cm 1:1.1 in 1956. The 3.5cm 1.8 was Nikon’s shot across Leica’s bow, given Leitz’s preeminence in wide angle design, incorporating the highest technology of the period to produce optics as good, or better than, the Leitz offerings……

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