what is nikon f?
Nikon F-mount. The Nikon F-mount is a type of interchangeable lens mount developed by Nikon for its 35mm format Single-lens reflex cameras. The F-mount was first introduced on the Nikon F camera in 1959, and features a three-lug bayonet mount with a 44 mm throat and a flange to focal plane distance of 46.5 mm. The company continues to use variations of the same lens mount specification for its film and digital SLR cameras.