The 50mm f/1.5 is one of the rarest of all Nikon lenses, produced less than a year in 1950 for the unsynced Nikon M. It was Nikon's first "Super-speed Lens." The 50mm f/1.5 was soon replaced by the even faster 50mm f/1.4 so Nikon could have temporary bragging rights of producing the world's fastest 50mm lens. It was produced only in chrome, with a surprising minimum aperture of f/11. The 50mm f/1.5 Nikkor has sometimes been mistaken for the very similar 50mm f/1.4 by those who just don't bother to read the f/stops -- to the delight of buyers and dismay of sellers. Total production in both Nikon and Leica screw mounts was about 800. It is estimated about 300 were Leica screw mount, leaving only about 500 to satisfy Nikon rangefinder collector's quest to have Nikon's 1st super speed lens, making the 50mm f/1.5 rarer than even the 50mm f/1.1.
The oddest thing about the 50mm f/1.5 is the aperture ring. Unlike the later 50mm f/1.4, the outer knurled ring does NOT turn. It is fixed. To change apertures on the 1.5, turn the inner, or 2nd knurled ring! Surprisingly, the 50mm f/1.5 has the same 40.5 filter size as the slower 50/2 Nikon. It has 7 elements in 3 groups, similar to the later 50mm f/1.4, with no less than a dozen diaphragm blades! Take note that although it will fit properly on any Nikon rangefinder, the 50mm f/1.5 was originally made for the unsynced Nikon M.
