Nikkor-S 5cm f1.4 from the Allied Occupation era. White barrel. Marked Nippon Kogaku Tokyo. Serial number 317555, with matching last three digits. Nikon S internal bayonet mount.

This is a Nikkor lens from the era of Nikon M, MS, and early Nikon S bodies, when the cameras were engraved with Made In Occupied Japan (MIOJ). It is estimated to have been manufactured between 1950 and 1951.

Constructed with a 3-group, 7-element Sonnar-type design. Filter diameter is 43mm. At the time, it was the first 50mm lens in the world to achieve an f1.4 aperture, although it was said to be closer to f1.5 in actual performance.

The rendering is soft at wide open to around f2, but stopping down to f4 transforms the image sharply. In recent years, a variety of adapters for Leica and mirrorless mounts have become available, offering expanded ways to enjoy this lens.

There are minor scuffs on the barrel and some shine on the knurled parts, but no noticeable scratches or dents. Considering its age, the lens is in good cosmetic condition for a Nikkor of this era.
Fully overhauled in July 2025, including cleaning of the aperture blades.
The front element shows a few faint cleaning marks, but they have virtually no impact on image quality. The glass is clear with no haze.
Included are a later-period plastic front cap with the Mt. Fuji logo, an aluminum rear cap, and a leather case.