Nippon-Kogaku Nikkor QC 13.5cm f/3.5

Nippon-Kogaku Nikkor QC 13.5cm f/3.5

Among the long lenses built around Nikon's rangefinder system, the Nikkor-Q.C 13.5cm f/3.5 is a compact telephoto whose name encodes its construction: in Nippon Kogaku's lettering scheme the "Q" (from the Latin quattuor) signals a four-element design, and the trailing "C" marks the optics as coated [1]. The lens was produced for Nikon's S-series rangefinder bodies and was also supplied in a Leica thread mount, which lets it couple to the rangefinders of LTM cameras[2]. Period examples carry the Nippon Kogaku Japan engraving and the red "R" focusing index common to the maker's rangefinder telephotos of the era.

Optically the lens uses four elements arranged in three groups, a classic short telephoto layout for the focal length, and it stops down with a ten-blade aperture that gives a near-circular opening. It focuses to a minimum of 1.5 m and accepts 43 mm filters. The barrel was offered in both black and silver (chrome) finishes and weighs about 406 g, making it a manageable companion to a rangefinder body. Focusing is helical and the mount is rangefinder coupled, so the lens drives the camera's coincident-image rangefinder directly rather than relying on an accessory or guesswork.

The lens appears in collector listings under the closely related Nikkor-Q and Nikkor-Q.C designations, the difference being the coated optics indicated by the "C" suffix[3]. Examples are documented in black-and-chrome trim, and a scarcer all-black version marked "E.P." (a designation tied to military and export Post Exchange sales) is also known. Buyers should confirm which mount a given example carries, since the same optical unit was sold in Nikon S bayonet, Contax-compatible, and Leica screw forms.

Optical qualities

Rendering Documentation of this specific lens's rendering is limited, and detailed independent test data is sparse. What can be stated with confidence follows from the design itself: a coated four-element telephoto of this period is built for moderate contrast and controlled flare relative to uncoated predecessors, with the coating ("C") intended to improve light transmission and reduce internal reflections. The ten-blade diaphragm supports a rounded out-of-focus rendering when stopped down. Absent corroborating measured results, no specific claims about edge sharpness, distortion, or vignetting are made here.

History

Development and Launch The Nikkor-Q.C 13.5cm f/3.5 belongs to the family of interchangeable lenses Nippon Kogaku built for its rangefinder cameras, the line that culminated in the Nikon S, S2, and SP bodies. As the moderate telephoto in that kit, it complemented the standard 5cm lenses and the shorter portrait-length Nikkors, and its coated four-element design reflects the postwar move from uncoated to coated optics across the range.

Production Evolution The lens is recorded both as Nikkor-Q and Nikkor-Q.C, the latter denoting the coated version, and was supplied in black and chrome barrels as well as in different mounts for the Nikon, Contax, and Leica-thread ecosystems. A dedicated repair and teardown of the Nikkor-Q.C 13.5cm f/3.5 rangefinder lens has been published, indicating the barrel is serviceable by experienced technicians.

Special editions No broad family of factory special editions is widely documented for this lens. A rare all-black example marked "E.P.," associated with military and export Post Exchange distribution, has appeared in the collector market.

Collector Notes When evaluating an example, verify the mount first, because the optical unit was sold in Nikon S, Contax, and Leica screw forms, and a lens advertised for one system will not couple correctly on another. Confirm that the engraving reads Nippon Kogaku Japan and check for the coated "C" designation if that variant is wanted. As with any lens of this age, inspect the coatings and internal elements for haze and cleaning marks, and confirm smooth helical focus and a clean ten-blade diaphragm; the existence of a published teardown suggests cleaning and re-lubrication are feasible if needed. Original caps, the matching hood, and 43 mm filters are worth confirming before purchase.