Technical terms of camera lens

Due to the use of aspheric lenses, lenses with special optical characteristics can be made. Using aspherical lenses means that the lens can be made smaller and lighter, which is usually better than similar lenses that only use spherical lenses. Nikon introduced the first aspherical lens camera lens with 1968: 10mm F5.6 OP fisheye. The world's fastest 28mm lens (AF Nikkor 28mm f/ 1.4D) adopts aspherical lens to ensure its compact structure. By eliminating radial latent light or arrow coma, it can even achieve excellent performance with its maximum aperture. The surface of aspheric lens is an ideal curved surface, which can correct these aberrations. Aspheric lenses-even with the largest aperture-can actually eliminate coma and other types of lens aberrations. They are very useful for correcting the image distortion formed by wide-angle lenses. Nikon uses three kinds of aspherical lenses:

Precision grinding aspheric lens is the highest expression of lens manufacturing technology, which requires extremely strict manufacturing standards.

Hybrid lenses are made by casting special plastic on optical lenses.

Aspheric lens with molded lens is manufactured by using special metal mold technology to mold a specific type of optical lens.

For details about aspheric lenses, please click here.

Auto focus DC- nikkor lens

One of Nikon's unique contributions to portrait photography is Nikon's proprietary defocused image control DC (defocused image control) technology.

This innovative Nikon technology allows users of autofocus DC- nikkor lens to control the spherical aberration of the foreground or background by rotating the DC ring of the lens, so as to accurately control the ambiguity of the background and foreground, and thus shoot beautiful human images. This will create a circular blur suitable for portrait shooting. These lenses are unique to Nikon.

AF-S nikkor lens

Nikon's AF-S technology involves ultra-telephoto lenses such as 300mm, 400mm, 500mm and 600mm, and zoom lenses such as 17-35mm, 28-70mm and 80-200 mm with fast maximum aperture ... This enables these lenses to perform autofocus operation quickly and quietly, thus making them suitable for shooting sports and operation scenes quickly. Nikon integrates this technology into Nikon's various lenses, such as the 24-85 AFS–G lens.

SWM technology used in Nikon AF-S lens focuses light by converting traveling waves into rotational energy. Ultrasonic traveling waves can form spiral patterns in the lens barrel. The motor is located at the top of the traveling wave, which drives the motor from below. In principle, it's similar to surfing. Traveling waves drive or push surfers to keep their balance. This can make high-speed autofocus very accurate and quiet. The lens receives power and focusing instructions from the camera body to drive the internal focusing motor, so it can only be used on a suitable camera.

AF-S motor

Short range correction (CRC)

Close focus is a very desirable feature for all lenses. The closer the focal length of a telephoto lens is, the more realistic the photos will be. Even if you use a wide-angle lens that can focus at close range, you can shoot interesting perspective images.

AF 24mm F2.8D

Nikon is a pioneer in the development of short-range correction (CRC) system. Sometimes referred to as a "floating lens" design, each lens group moves independently to achieve precise focusing. This ensures the best lens performance even when shooting at close range. CRC system is used in fisheye, wide-angle, macro and some nikkor lens with medium and long focal length, which makes it perform well in both short-range and long-range focusing. Nikon designers have been trying to provide advanced and efficient functions for Nikon nikkor lens, and CRC is another example.

range information

D-type and G-type Nikon can transmit the distance between the object and the camera to the body of AF Nikon camera through the encoder in the lens. This makes it possible to improve the performance of supplementary flash, such as 3D matrix photometry and 3D multiple inductive equalization.

Advanced (short for deluxe)

Nikon has launched a series of new DX nikkor lens. These DX nikkor lens are specially designed for Nikon's "D series" SLR camera series (D 1, D 1X, D 100, D70 and D2H). In order to meet the requirements, digital images are made of 24 x 16 mm (approximate) photoreceptor formats. Please click here to learn more about DX lens.

Ultra-low dispersion lens

Ed (Ultra Low Dispersion) lenses developed by Nikon optical designers and Nikon lens experts are used in some telephoto and telephoto zoom lenses to provide clear and colorful images by effectively reducing the significant aberrations in telephoto lenses. In short, aberration is the image and dispersion formed when light with different wavelengths passes through an optical lens. The best explanation is that white light is composed of three colors (red, blue and green). When the light passes through the lens, it is separated, and as a result, it is not recombined in the correct position to produce a clear image, thus forming this phenomenon.

ED lens can prevent this scattering/separation of light, so it can produce clear images. In the past, special optical lenses with irregular scattering characteristics, especially calcium fluoride crystals, were needed to correct this problem. However, fluorite is easy to crack and sensitive to temperature changes, which may change the refractive index of the lens and adversely affect the focusing.

Nikon designers and engineers brainstormed and developed ed lens, which has all the advantages of calcium fluoride lens without its disadvantages. Using this innovative technology, Nikon has developed several ed lenses suitable for various lenses.

They also provide perfect clarity and contrast when the maximum aperture is used. In this way, Nicole ED series lens has become an outstanding representative of Nikon's innovative and efficient lens.

G–g series

Nikon has launched a series of new lenses called AF-G. Please click here for details about G series lenses.

If the internal focus

Nikon's IF technology can focus without changing the lens size. As early as 1977, when Nikon introduced the IF lens, in order to move the front lens back and forth, the telephoto lens needed to rotate the focusing ring for a long time to get the longer lens you needed for focusing. For some larger telephoto lenses, a special screw handle can be added to facilitate focusing. With the IF design, the movement of all internal optical lenses is confined to the inside of the non-extended lens barrel.

This can make the structure of the lens smaller and get a closer focal length. In addition, a smaller and lighter focusing lens group is adopted to ensure fast focusing. Most Nicole telephoto lenses and some Nicole zoom lenses use intermediate frequency systems. Among them, AF-S Nikkor has actually become the standard equipment of the rapidly developing sports photography in the world.

Nanocrystalline coating technology

Nikon has developed nanocrystalline coating, which is a new anti-reflective lens coating technology, which can reduce ghosts and spots, especially images taken in strong sunlight or light.

An image taken with a lens without a nanocrystalline coating an image taken with a lens with a nanocrystalline coating.

This technology was developed as a by-product of Nikon NSR (Nikon Distribution and Repetition) semiconductor manufacturing system.

Nanocrystalline coating seen under microscope

Fresnel phase

By using and relying on more advanced optical technology, Nikon can manufacture phase Fresnel (PF) lenses, and can make smaller and more economical telephoto lenses. The first telephoto lens using this technology is TC-E3PF of COOLPIX 8400, which is shorter than TC-E3ED by 18% and lighter by 33%.

The cross-sectional view of TC-E3PF highlights the PF lens in yellow.

An advanced property of PF lens is that it can correct aberration in a way similar to ed lens. With its professional manufacturing experience and production capacity of aspheric lens, Nikon can also successfully apply this technology to other types of lenses.

Focus backward

In Nikon's backward focusing (RF) system, all lenses can be divided into specific lens groups, and only the rear lens group moves when focusing.

Af-DC135mm F2D

Because the rear lens group is smaller than the front lens group, especially in the high-speed telephoto lens group, radio frequency technology can make the lens group move more smoothly and quickly. Radio frequency can also bring high optical performance.

Ultra HD lens

Super ED lens is another new development of Nikon's own ED lens technology. Nikon optical designers and Nikon lens experts jointly developed super ED lenses, whose optical characteristics are similar to those of fluorite lenses. The reflectivity and optical dispersion of super ED lens are even lower than that of ED lens, and it has better performance in eliminating secondary spectrum and correcting aberration.

AF-S VR 200mm F2G intermediate frequency sharpening lens

Super ED lens is not as easy to crack as fluorite lens, and its optical properties change less than fluorite lens when the temperature changes sharply (called thermal shock). The lens with super ED lens can provide excellent optical performance even in harsh shooting environment, and can shoot clear and bright images even with the fastest aperture. Nikon promises to constantly innovate and improve the performance of optical lenses, and super ED lens is another example.

Super coating-silicon carbide

In order to improve the performance of its optical lens, Nikon adopted a unique multi-layer lens coating technology to reduce ghosts and light spots to negligible levels. Nikon's breakthrough NIC coating technology has been improved, and Nikon's super coating has brought many advantages, including reducing reflection in a wider wavelength range, better color balance and reduction. Nikon super coating is very effective for lenses with many lenses (such as zoom Nico).

The top half of this lens is not coated with SIC, while the buttons are coated with SIC.

At the same time, Nikon's multi-layer coating process is perfectly combined with the design of each special lens. After careful calculation, the number of coating layers of each lens is completely suitable for this lens. The type and lens used ensure a consistent color balance, which is the characteristic of nikkor lens. Therefore, this kind of lens has a higher standard than other industries.

Vr–damping system

This innovative system can prevent blurred images caused by camera vibration and provide the effect equivalent to shooting at three shutter speeds. It allows manual shooting in dusty, night and even poor light internal environment. The VR system can also automatically detect when the photographer takes a panoramic view-no special mode is needed.

The VR lens group is equipped with two angular velocity sensors. One is used to detect "pitch" (rotating up and down on a specific axis) and the other is used to detect "deflection" (rotating left and right on a specific axis).

Calculate immediately according to the collected data, and use the results to calculate the target position to which the VR lens group will move. Then, VCM will move the VR lens group to this position. This is not a simple drive, but a continuous monitoring action, which means that the processor will constantly check whether the lens is in the correct position. Incredible as it may be, all these operations are completed by the microprocessor in 1 millisecond (only one thousandth of a second).

Fortunately, VR nikkor lens is very advanced. It can actually judge whether the action is intentional (such as panoramic shooting) and only correct it as unconscious action. Its principle lies in the built-in algorithm in VR nikkor lens. These algorithms are developed based on about 5000 vibration data samples of cameras, and under what circumstances the types of camera vibration can be judged. The VR mechanism is to let the photographer (with or without experience) move the lens at will, and only correct all the unexpected manual actions of the photographer.

Virtual reality lens equipment

VR nikkor lens can bring convenience to photographers in many ways. The slower shutter speed can be selected by three-level speed adjustment, which makes the lens suitable for telephoto shooting in scenes such as night football matches. It is also more convenient to use color reversal films with low sensitivity. By lowering the shutter speed limit, you don't need to bring a tripod at any time. Canon high-end EF lens technical terms

Image stabilizer

Image Stabilizer, English name: image stabilizer.

A big obstacle to shooting is "jitter". Usually, in order to avoid jitter, it is necessary to adopt a shutter speed faster than "1/ focal length" seconds. However, if you shoot in a dark place, or use a hand with low sensitivity, you must slow down the shutter speed, which will easily blur the shot picture. The image stabilizer independently developed by Canon compensates for jitter by moving some optical systems in parallel, thus reducing the shooting failure caused by jitter.

In real life, carrying a tripod is a very troublesome thing. For example, when hiking, traveling or using a tripod are not allowed, it is difficult to avoid image blur when shooting in low illumination, no matter how stable the hand-held camera is. Canon has a way to solve this problem. A kind of SLR mirror with built-in image stabilizer has been developed successfully. According to the vibration angle and times of the lens, the rotating unit and the moving optical system of the optical compensation system will perform compensation motion to correct the vibration.

Ultrasonic motor

The ultrasonic motor (USM) in Canon EF lens is driven by ultrasonic vibration force, which is fast and quiet, making the autofocus operation of EF lens fast, accurate and almost silent. This kind of direct drive structure is very simple, which improves durability and work efficiency. Ultrasonic motors are divided into two types: ring and miniature. The former is mostly used for large aperture and super telephoto lenses; The latter is mostly used for economical lenses. Proper use will make the autofocus effect better.

Make a shot

If the refractive index of light passing through the lens changes, it will lead to color bleeding (color difference), which will lead to the decline of image quality. In order to compensate it, it is necessary to combine multiple convex mirrors and concave mirror to offset it. Therefore, the original telephoto lens and zoom lens need to use multiple lenses, resulting in a large lens volume. Canon took the lead in developing "DO (Diffractive Optics) lens" for cameras, which successfully solved these problems.

Super UD lens /UD mirror

UD (Ultra Low Dispersion = Ultra Low Dispersion) lens developed by Canon is an optical lens with low refraction and low dispersion. Two UD lenses can obtain almost the same high-performance optical characteristics as fluorite lenses. Carl zeiss from Germany, with advanced optical technology, will be an optical layman of Sony. With strong technical support, Sony has become a big name of consumer-grade DC. Sony's SLR cameras are constantly innovating and constantly correcting various problems. The SLR market has changed the situation that two companies dominate and three companies divide the world. Sony and carl zeiss used a variety of high-end optical SLR lenses together. Unfortunately, the lack of a rich lens product system has led to the situation that customers can afford the machine but can't afford the lens. However, domestic players are turning to manufacturers such as Longteng!

1.ZA series

ZA series lens, according to official website, is an autofocus SLR lens jointly produced by Sony and Zeiss. Lens The optical lens is provided by Zeiss, and the electronic system is designed by Sony. ZA series lens is the only Zeiss brand lens with autofocus function. According to the tests of websites such as photodo, the optical quality of ZA lens is excellent, which can meet the demanding requirements of high-pixel digital SLR cameras for resolution. Including:

Sony α carl zeiss distagont *1:2 24mm zassm [sal-24f2z]

Sony α carl zeiss plane t *1:1.4 85mm za [sal-85f14z]

Sony α carl zeiss Sonnar T *1:1.8135mm za [sal-135f18z].

Sony α carl zeiss vario-sonnart * dt1:3.5-1:4.516-80mmza [sal-1680z]

Sony α carl zeiss Vario-Sonnar T *1:2.8 24-70mm ZA SSM [SAL-2470Z]

Sony α carl zeiss vario-sonnart *1:2.816-35mm zassm [sal-1635z]