Nikkor 55mm f1.2 First produced in December 1965
From "The Complete Nikon System" by Peter Braczko
With this fast standard lens, Nikon met the needs of photographers who had to work under extremely poor lighting conditions; however,
miracles in image quality couldn't be expected when the lens was used at full aperture. The 55mm f/1.2 was the first Nikkor to use a new method of applying multi-layer lens coatings in the production process.
The large front lens element is surrounded by the lens data engraving inside the front of the focusing barrel. The aperture ring has an easily-gripped scalloped design, and the lens has a wide mounting ring.
The unusually large rear lens elementis a notable feature. Early examples, which can be recognised by their Nippon Kogaku engraving, have the triangular meter coupling prong which was later changed to a semicircular shape for use with Photomic attachments.