
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 1958, and features a three-lug bayonet mount with a 44mm throat and a flange to focal plane distance of 46.5mm. The company continues, with the 2020 D6 model, to use variations of the same lens mount specification for its film and digital SLR cameras.
History.
The Nikon F-mount is one of only two SLR lens mounts (the other being the Pentax K-mount) which were not abandoned by their associated manufacturer upon the introduction of autofocus, but rather extended to meet new requirements related to metering, autofocus, and aperture control. The large variety of F-mount compatible lenses makes it the largest system of interchangeable flange-mount photographic lenses in history. Over 400 different Nikkor lenses are compatible with the system (other details can be found at the Nikkor "The Thousand and One Nights" site). The F-mount is also popular in scientific and industrial applications, most notably machine vision. The F-mount has been in production for over five decades, making it the only SLR lens mount which has been produced for over 50 years.
System of lenses.
In addition to Nikon's own range of "Nikkor" lenses, brands of F-mount photographic lenses include Zeiss, Voigtländer, Schneider, Angénieux, Samyang, Sigma, Tokina, Tamron, Hartblei, Kiev-Arsenal, Lensbaby, and Vivitar. F-mount cameras include current models from Nikon, Fujifilm, Sinar, JVC, Kenko and Horseman. Numerous other manufacturers employ the F-mount in non-photographic imaging applications.
Compatibility.
The F-mount has a significant degree of both backward and forward compatibility. Many current autofocus F-mount lenses can be used on the original Nikon F, and the earliest manual-focus F-mount lenses of the 1960s and early 1970s can, with some modification, still be used to their fullest on all professional-class Nikon cameras. Incompatibilities do exist, however, and adventurous F-mount users should consult product documentation in order to avoid problems. For example, many electronic camera bodies cannot meter without a CPU enabled lens; the aperture of G designated lenses cannot be controlled without an electronic camera body; non-AI lenses (manufactured prior to 1977) can cause mechanical damage to later model bodies unless they are modified to meet the AI specification; and AF-P lenses (introduced in 2016) will not focus, even manually, on cameras introduced before roughly 2013. Many manual focus lenses can be converted to allow metering with consumer Nikon bodies by adding a Dandelion chip to the lens.
Image circle.
Most Nikon F-mount lenses cover a minimum of the standard 36×24mm area of 35mm format and the Nikon FX format, while DX designated lenses cover the 24×16mm area of the Nikon DX format, and industrial F-mount lenses have varying coverage. DX lenses may produce vignetting when used on film and FX cameras. However, Nikon lenses designed for film cameras will work on Nikon digital system cameras with the limitations noted above.
Mounting and control rings.
F-mount lenses lock by turning counter-clockwise (when looking at the front of lens) and unlock clockwise. Nearly all F-mount lenses have zoom and focus controls that rotate in the clockwise direction (as viewed from behind the camera) to increase focal length and focus distance respectively. This convention is also used in Pentax K-mount and Sony A-mount lenses but is opposite of the direction normally used by Canon. F-mount lenses also typically have aperture rings that turn clockwise to close.
Nikkor.
Designations.
Nikon has introduced many proprietary designations for F-mount Nikkor lenses, reflecting design variations and developments both in lenses and the F-mount itself. There are also "unofficial" designations used by collectors and dealers to differentiate similar lenses.
Manual-focus lenses.
Perspective control (PC) lenses.
Nikon PC lenses, like other perspective control lenses, offer adjustments that duplicate certain view camera movements. The 28mm and 35mm PC lenses support shifting the lens in relation to the film or sensor plane, while Nikon's 19mm, 24mm, 45mm, and 85mm PC-E lenses also support tilting.
Nikon currently offers four different PC lenses for sale: the four PC-E Nikkors (2008 and 2016), and the 85mm PC-Nikkor (1999). The 45mm and 85mm "Micro" lenses offer close focus (0.5 magnification) for macrophotography. The PC-E lenses (the "E" designates an electromagnetic diaphragm) offer automatic aperture control with all DSLRs with CMOS image sensor except the Nikon D90. With earlier DSLRs and all "analog" film camera models, a PC-E lens operates like a PC lens. The PC Micro-Nikkor 85mm 2.8D lens offers only preset aperture control, actuated mechanically by pressing a plunger.
History.
In July 1962, Nikon released the first interchangeable perspective-control lens available for a single-lens reflex camera, the 35mm 3.5 PC-Nikkor. This was followed in 1968 by a redesigned 35mm 2.8 PC-Nikkor in which the shifting portion of the lens was further from the camera's body, in order to clear the new "Photomic" meters. The last optical redesign of this 35mm lens was released in 1980.
The 35mm PC-Nikkor did not meet the need of photographers for a wider-angle lens, so in July 1975 Nikon released the 28mm 4 PC-Nikkor. In February 1981 Nikon released an improved version of this lens, the 28mm 3.5 PC-Nikkor, with a new optical design. This was the last of the completely manual PC-Nikkors to be offered.
Automatic focus lenses.
Lenses with integrated autofocus motors.
Nikkor lenses designated AF-S, AF-I, or AF-P have integrated autofocus motors, but other manufacturers included in the list do not designate it as clearly. These lenses are needed for autofocus on certain newer low-end Nikon cameras which lack an autofocus motor. These are the Nikon D40, D40X, D60, D3xxx (most recent: D3400), D5xxx (most recent: D5600) and the Nikon 1 series with FT1 adapter.
Other Brands.
Zeiss ZF.
Zeiss ZF series lenses are manual-focus designs Nikon AI-S type aperture indexing. They are manufactured by Cosina to Zeiss specifications.
Four design variations are designated ZF, ZF.2, ZF-I, and ZF-IR.
ZF is the original product line. 
ZF.2 lenses are CPU-enabled (similar to Nikon AI-P lenses) offering full metering compatibility with the full range of AF Nikon SLR cameras. 
ZF-I lenses add mechanical locks for focus and aperture, and additional environmental sealing, for industrial applications. 
ZF-IR lenses are adapted to infrared imaging, with coatings that transmit wavelengths up to 1100 nm, and focus scales marked for infrared.
Zeiss CP.2.
CP.2 lenses are a series of Zeiss "CompactPrime" cinema lenses which present F-mount as one of three mounting options. The lenses cover the 36×24 mm area of the 35mm format or Nikon FX format, and lenses 28 mm and longer share a common T-stop (T/) of 2.1.