Bayonet - what is it? Nikon F mount

2024 Author: Sierra Becker | [email protected]. Last modified: 2024-02-26 03:46

Bayonet is the scientific name for a lens mount for photo and video equipment. It can be a mounting system or a special unit with which a lens is mounted on the camera. Leading camera companies have developed their own mount standards, so often a mount from one company is incompatible with another. However, there are standardized systems and additional devices (for example, a bayonet adapter) that allow you to install optics from different companies. The most common mount types are Nikon F, Canon EF and Sony E.

Nikon F mount

With the development of photography, it became clear that standard optics, tightly connected to the body of the device, are not able to satisfy the creative ideas of professionals. The solution was found in the use of interchangeable lenses. Nikon was one of the first to introduce the standard for fixing interchangeable lenses. A bayonet type, introduced by Nikon in 1959, is a bayonet-type connector used to connect a 35mm camera (body) and lens.

Lenses with the original F-mount system were used extensively until 1977, until a compatible lens appearedelement of type AI. Even modern Nikon lenses can be used with the Type F fixture and work fine with older cameras, although mounting may require minor mechanical adjustments.

Operation principle

The bayonet is a fairly simple device. In order to attach an F-type lens to the camera, one must manually align the protrusion on the lens with the metering bar, which was fixed at f/5.6. Later, this type of lens was also referred to as pre-AI or non-AI.

Compatibility

Nikon F mount lenses work great with all modern Nikon cameras at least in manual exposure mode, especially if modified to be compatible with AI mount. In this case, the operation of the aperture priority modes will depend on the camera model. Matrix metering requires special upgrades to the mount, so it usually won't work with these lenses, even if they're upgraded to AI standard.

Design Features

Already starting with lenses equipped with the Nikon F mount system, the company used a jump aperture mechanism. That is, this detail is constantly open when focusing and closes only an instant before the moment of photographing. This ensures that the image in the viewfinder does not darken or hinder aiming even when the aperture ring is turned to the closed position. Structurally, this is implemented in the form of a lever built into the camera socket, which is lowered beforeto take a photo. Another lever is released in the lens, which, under the action of a spring, closes the aperture blades.

Nikon mount type AI

AI (Automatic Indexing) - an improved version of the first Nikon F mount - was proposed in 1977. Fans of Nikon products were waiting for an updated system that made it possible to change optics faster. Sometimes a masterpiece is separated from a mediocre photo by a few wasted seconds spent on changing lenses. And the photo giant introduced a new mount. This is a modernized design that allows you to put the lens with one hand movement and not waste time hitting the index bar with the aperture ring.

When used on modern cameras, AI lenses can work in modes such as manual (M) and aperture priority (A) with spot or center exposure metering. Some cameras may also use the matrix metering method.

Old-style (F) lenses are very easy to upgrade to AI by building up a protrusion that, by touching the lever in the camera mount, reports the position of the aperture ring.

Innovations

It was expected that the main innovation would be the establishment of mechanical levers that should tell the camera about the focal length of the lens. Experts assumed that the new Nikon cameras would somehow use this information. But this did not affect the upgraded mount. The designers went the other way: modern lenses transmit the necessary information electronically. This methodturned out to be much cheaper and more reliable. AI lenses are now sold for next to nothing, although they are not inferior to modern AI-S (for example, they do not have a quick program mode).

Soviet and Ukrainian cameras and lenses

On the territory of the USSR and Ukraine, 35 mm cameras and lenses compatible with the Nikon AI mount were produced by the Kyiv Arsenal plant. Among the cells were the following:

• Kyiv-17;
• Kyiv-20;
• Kyiv-19;
• Kyiv-19M;
• Arsat lens line.

Nikon AI-s mount

This is the next evolution of interchangeable lenses. This device is still in use today. It is easy to cast it from AI by the specific rounded cutout on the mount, the depth of field scale on the chrome ring (in AI the surface is black), the minimum aperture designation applied in orange paint.

The letter "S" means that the aperture closing ratio linearly affects the deviations of the aperture indicator lever in the bayonet. Thanks to the innovation in cameras with autofocus, the accuracy of aperture measurement has been significantly improved. For manual models, this improvement does not matter.

Compatibility with previous types

• All AI-S lenses are compatible with AI lenses.
• All AF, AF-I and AF-S lenses are also compatible with the AI-S mount system.
• All AI-S lenses work on Nikon DSLRs in at least manual mode.
• Most Nikon SLR cameras, including digital ones, canOperate in Aperture Priority mode except for some consumer-grade devices.

Before planning a purchase, please read your camera's user manual, which always provides information on support for specific lens types.

P-type mount

This hybrid standard was introduced in 1988 specifically for telephoto manual lenses, which were supposed to hold Nikon's position until telephoto AF lenses became mainstream. At that time, the best "auto focusers" were models with parameters 300 mm f/2 8.

Nikon released a few P-type lenses, including the 500mm f/4 P (1988); 1200-1700mm f/5, 6-8, 0 P ED; 45mm f/2, 8 P.

P-type lenses are manual AI-S with a few electronic AF mount contacts added. This approach made it possible to use the matrix metering mode, which only appeared on autofocus cameras.

AF mount

Nikon's autofocus AF lenses (except AF-I and AF-S) are focused by the rotation of a motor in the camera, which is transmitted through a special mechanism to the detachable lens. Photographers called such a mechanism a “screwdriver”. Now this system looks primitive compared to Canon's autofocus system, but this design made it possible back in 1980 to maintain full compatibility with non-autofocus lenses. All autofocus devices (including AI-S) work fine on non-autofocus cameras. However, devices that do not supportAI will still need improvement.

AF-N type mount

The AF-N designation was introduced only to distinguish older series AF lenses from newer ones. After the release of the first AF lenses, Nikon decided that with such a convenient technology, no one would photograph in manual mode again. Therefore, the first AF lenses were equipped with a thin, uncomfortable manual focus ring, which was almost impossible to use. However, it turned out that photographers prefer the good old wide rubberized focus rings. Therefore, the engineers returned them back to autofocus lenses and called the new modifications AF-N. Modern lenses have convenient focus rings, so the AF-N designation no longer applies to them.

AF-D type mount

Lenses in this category tell the "intelligence" of the camera about the distance at which they are focused. Theoretically, in specific situations, this should help the matrix metering system determine the exposure more accurately, especially when using a flash. But in practice, the AF-D mount has more marketing value than practical. Moreover, the presence of AF-D can even cause incorrect exposure if the flash and the sensor (film) are at different distances from the subject.

Focus speed has nothing to do with the presence or absence of AF-D mount support. It's just that these are newer lenses, so they function faster than their predecessors. All AF-D lenses, like AF and AI-S, work great on non-AF cameras.

Canon EF

The mount is not a Nikon exclusive concept. Other companies also developed their interchangeable lens mount systems. Eternal competitor - Canon - is also famous for its thoughtful types of mount designs. At a time when Nikon was pushing the AI-S system, Canon was showing off a great EF mount.

The Canon mount first appeared on the EOS 650 in 1987 when the company launched its autofocus SLR series. This element differed from analogues, first of all, by the presence of electrical contacts, through which control information was transmitted to the lens. At the same time, mechanical aperture control, autofocus drive and some other properties were abandoned in the EF mount. Much later, a similar control option was used by Olympus in the Four-Thirds system.

Canon EF-S

The EF-S option provides a short distance from the rear lens to the image sensor. It is partially EF compliant because EF mount lenses can be used in EF and EF-S mount cameras.

Sony E-mount

E-mount is Sony's proprietary lens mount for Alpha NEX series mirrorless cameras and NXCAM camcorders. This is a fairly recent development, introduced in 2010 and implemented for the first time in Sony α series products (NEX-3, -5 cameras). The connection feature of the E-mount system is a ten-pin digital interface.

Bayonet with index"E" is used in mirrorless compact cameras equipped with sensors that produce image quality at the level of "DSLRs". At the same time, for SLR cameras, Sony engineers use the A-mount for advanced interchangeable lenses with a system of translucent mirrors. The two systems, in addition to some design features, differ in the size of the working distance. This is the distance from the focal plane (matrix) to the end of the lens. In SLR cameras, the matrix and the lens are separated by a mirror, so the working distance is large, and the physical size of interchangeable lenses increases. The E-mount device does not require a mirror, so the lenses are much lighter and more compact.

Compatible with third party products

Surprisingly, Japanese designers did not go their own way, but chose an openness strategy. Features such as the Sony E mount allow the production of specialized adapters that connect the lens to almost any modern mount from the following companies:

• Pentax;
• Olympus;
• Nikon;
• Leica;
• Hasselblad;
• Exacta;
• Minolta AF;
• Canon EF;
• Contarex;
• Contax;
• Rollei;
• Micro 4:3;
• Threaded T-mount, type C, M39×1, M42×1 and others.

In 2011, the company unveiled features of the Sony mount, allowing third parties to manufacture their own lenses for Japanese cameras.

Conclusion

At first glance, the bayonet is not a technically complex design. However, this node performs several important functions. It allows you to change the types of lenses depending on the tasks performed, and the more thoughtful the design, the faster and more convenient the replacement of optics. The second important task is the transfer of digital information in modern cameras through electrical contacts on the lens and mount, which allows the lens and camera to synchronize to get the highest quality pictures and video frames.