Nikon's long telephoto — the manual-focus Nikkor-H Auto 300mm f/4.5 for the F mount, wildlife reach.
The Nikkor-H Auto 300mm f/4.5 is a long telephoto for the Nikon F system, introduced in the late 1960s. The H code marks its element count, and it gave F-system photographers substantial reach for wildlife, sport and distant subjects at a moderate f/4.5 aperture, in a design lighter than the fast super-telephotos of its day.
This is a manual-focus Nikon F lens with a maximum aperture of f/4.5 and a fixed 300mm focal length, using an automatic diaphragm for full-aperture viewing. It is a long telephoto operating with normal reflex viewing on the F system. Only the verified focal, aperture and mount are stated; construction details are omitted to avoid error.
The 300mm focal length gives strong reach and heavy compression for distant subjects, with the f/4.5 aperture balancing size against speed. It suits wildlife, sport and other distant subjects, typically on a tripod or with support given the long focal length. Sharpness is good stopped down, and careful technique keeps images crisp.
On the used market the Nikkor-H 300mm f/4.5 is collectible and fairly available, valued as an early long tele. Inspect the elements for haze, fungus and separation, check coatings, confirm the automatic diaphragm operates, and test the long focus throw for smooth action. It adapts to mirrorless where its reach remains useful, though a support is advisable.