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 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.
The Nikon F-mount successor is the Nikon Z-mount. The FTZ II lens adapter allows many F-mount lenses to be used on Z-mount cameras.
History
The Nikon F-mount is one of only two SLR lens mounts 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. The F-mount is also popular in scientific and industrial applications, most notably machine vision. The F-mount has been in production for over years, the only SLR lens mount with such longevity.Design
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 can cause mechanical damage to later model bodies unless they are modified to meet the AI specification; and AF-P lenses 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 and unlock clockwise. Nearly all F-mount lenses have zoom and focus controls that rotate in the clockwise direction 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. The aperture rings have two sets of f-stop numbers. On cameras equipped with Nikon's Aperture Direct Readout system, a small window under the pentaprism reads the smaller scale and displays the selected f-stop in the viewfinder.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.Pre-autofocus
There are four major generations of manual-focus Nikkor lens styles, which may be distinguished cosmetically and functionally:Image:Nikon F SLR camera with NIKKOR-S Auto 1,4 f=5,8cm.JPG|thumb|upright=1.2|Nikon F professional SLR camera with eyelevel prism and early NIKKOR-S Auto 1,4 f=5,8cm lens
; A — Auto Nikkor, introduced in 1959: Designation for the first generation of F-mount lenses, introduced in 1959. These were all single-coated, and meter coupling was provided by a prong fixed to the lens's aperture ring. The Photomic T through-the-lens light meter introduced in 1965 worked at full aperture, so the maximum aperture of the lens had to be communicated to the meter via a manual setting on the ASA dial. The Nikkormat FTn and FTn metered finder for the Nikon F introduced semi-automatic aperture indexing which was achieved by mounting the lens with the aperture ring set to 5.6, and then turning the ring to first the minimum and then the maximum apertures. Early versions are marked "Nippon Kogaku Japan" and have their focal lengths stated in centimetres, but models produced after about 1965 have focal lengths stated in millimetres. The "Nippon Kogaku Japan" engraving was replaced by "Nikon" from 1971 onwards.
Mounting a non-AI lens can damage many modern Nikon camera bodies. AI-cameras that still may use non-AI lenses includes the Nikon F2A/F2AS with Photomic A or AS finder, Nikon EL2, as well as Nikon FM and FE. In addition, the Nikon Df, a DSLR introduced in late 2013, can use non-AI lenses. The A lenses can be converted to the AI specification; see AI'd below.
Image:Nikon F2 SB SLR camera with GN Auto Nikkor 2,8 f=45mm lens.JPG|thumb|upright=1.2|Nikon F2SB professional SLR camera with GN Auto Nikkor 1:2,8 f=45mm AI lens
; K — "Modern" or "New" Nikkors introduced in 1974: While Pre-AI for compatibility purposes, K-type lenses introduced the new cosmetics that would be used from 1977 onwards for AI-type lenses. The scalloped-metal focus rings were replaced with rubber grip insets, and the use of element number and coating designations was discontinued. The 'K' designation itself is believed to be derived from the Japanese "konnichi-teki", loosely translatable as "modern" or "contemporary".
; AI — Manual focus with "Automatic Maximum-Aperture Indexing," introduced in 1977: The AI standard adds a Meter Coupling Ridge to the aperture ring, which encodes the current aperture setting relative to the maximum, and a Lens Speed Indexing Post on the mounting flange, which encodes the maximum aperture itself. The Ridge and Post couple to the camera's light meter. Lenses designated AI-S, Series E, and AF all include these features of AI. Current professional Nikon camera bodies link with the Meter Coupling Ridge, but the Lens Speed Indexing Post is ignored and the maximum aperture value is set electronically by the operator instead. AI-designated lenses also improved on the original Meter Coupling Prong, adding cutaways which allow more ambient light to fall on the aperture ring, increasing visibility on cameras which optically projected the setting inside the viewfinder.
Image:NikonFE2blkfrt50f14.jpg|thumb|upright=1.2|A typical AI-S lens: A Nikkor 50mm 1:1.4 showing "Nikon" engravings, rubber focus ring, and new-style Meter Coupling Prong distinguished by its cutaway sections. The lens is mounted on a Nikon FE2 camera.
; AI-S — AI lenses with standardized aperture control, introduced in 1981: The successor to AI, the AI-S specification added two mechanical enhancements — standardized aperture control, and the Focal Length Indexing Ridge — required for the shutter priority and other auto-aperture exposure modes of the Nikon FA, F-301/N2000, and F-501/N2020 cameras. Later cameras did not require these features, and interoperate with AI and AI-S lenses identically. The term AI-S is now commonly used to refer to manual focus lenses, and Nikon continues to produce eight prime lens models in its AI-S line. All Nikon AF lenses with aperture rings also meet the AI-S specification, except for their lack of a Meter Coupling Prong. Visually, AI-S lenses can quickly be identified by the smallest aperture setting being marked in orange,
Autofocus lenses
; AF : The original autofocus designation, indicating focus driven by a motor inside the camera body. All AF lenses have an integrated CPU. Used in the form "AF Nikkor", this should not be confused with the original autofocus lenses for the F3AF camera, which were designated "AF-Nikkor" and are considered predecessors to AF-I lenses.;AF-N : Indicates the "New" version of an AF lens. The change from plastic focus rings on early AF lenses to the a new "rubber inset focus ring" is often indicated by the AF-N designation. Introduced in 1990.
;AF-I : Driven by a coreless DC motor. Used only in long telephoto lenses. Introduced in 1992.
;AF-D : Designation for an AF lens with "D" functionality. Introduced in 1992.
;AF-S : Uses a "Silent Wave Motor" to focus quietly and quickly. Similar to Canon's "USM" technology. Introduced in 1996.
;AF-P : Autofocus using a stepper motor. First F-Mount lens in 2015 after being introduced 2011 in the Nikon 1-mount. All DX AF-P lenses omit the physical AF/MF switch — those with Vibration Reduction omit the VR-switch.
Fully AF-P compatible without any firmware update are the Nikon D850, D500, D7500, D5600, D3400, D3500, Nikon-1 series with FT1 adapter and newer DSLR cameras. The Nikon Z-mount cameras with FTZ adapter are also fully compatible. Fully AF-P compatible after update are the Nikon D5, D5500 and D5300. After update the following cameras lack a software VR-switch: D4S, D4, D810, D810A, D800, D800E, D750, D610, D600, Df, D7200, D7100 and D3300 if the lens includes no physical VR-switch, VR is always on. Additionally they lack "Manual focus ring in AF mode", the manual override of autofocus.
The Nikon D3X, D3S, D3, D700, D300, D300S, D7000 and D2XS operate only AF-P FX lenses with additionally restrictions that after a reactivation from the standby mode a automatic or manual refocusing must take place as the focus is reset to infinity as they wake up. To avoid this, the standby time may be set in the camera for a longer time or "Unlimited". The D5200 works with DX and FX lenses, but additionally displays a "Lens not attached" message if a lens lock switch was activated when the camera is turned on.
The AF-P focus motor will not work with all Nikon film cameras and D1 to other D2 series, D200, D100, D5100, D5000, D90, D80, D70 series, D3200, D3100, D3000, D60, D50, D40 and D40X. Standard is VR = on and focus to infinity with all cameras only supporting E-type lenses. Not to be confused with old AI-P "Program" lenses.