How many kinds of camera lenses are there? Talk about the advantages of each type and the comparison of each type in detail.

Camera lens classification accurately, the lens can be divided into zoom and fixed focus. We just tried a zoom lens, which is a zoom lens, that is, a lens that can be pushed and pulled. In addition, there are fixed-focus lenses, that is, you can't change the focal length by only one focal segment or only one viewing angle. The appearance of the two lenses is obviously different. A fixed-focus lens has only one focus ring (which controls the definition, which will be introduced later), while a zoom lens has two rings, a focus ring (which controls the definition) and a zoom ring (which controls the viewing angle, that is, push and pull).

Fixed-focus lenses are easy to classify because of their fixed focal length: wide-angle lenses: generally, lenses below 35mm are wide-angle lenses, and lenses below 28mm are super wide-angle lenses. Wide-angle lens has a wide angle of view, a strong sense of depth, and the scenery will be deformed, which is more suitable for shooting larger scenes, such as buildings and gatherings. Medium focus lens: Generally, lenses from 36mm to 134mm are medium focus lenses. The medium focus lens is close to people's normal perspective and perspective, and the deformation of the scene is small, so it is suitable for taking portraits, landscapes, tourist commemorative photos and so on. Telephoto lens: Generally, lenses higher than 135mm are telephoto lenses, also called telephoto lenses. Among them, the lens larger than 300mm is a super telephoto lens. The telephoto lens has small viewing angle, weak perspective and small scene deformation. Suitable for shooting things that are inaccessible, such as wild animals and stages. It can also be used to blur the background and shoot portraits. The zoom lens is difficult to be generalized because of the change of focal length. Assuming that its focal length changes between one or two segments of wide-angle, medium-focus and telephoto, it can also be called wide-angle zoom lens, medium-long zoom lens and so on. See (published by Electronic Industry Press) [1] Editing various lenses and technical terms in this paragraph. Nikon's technical terms aspherical lens-ASP can make lenses with special optical characteristics because of the use of aspherical lenses. 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 adopted three kinds of aspheric lenses: precision grinding aspheric lenses is the highest expression of lens manufacturing technology and 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 Nikon's unique contribution to portrait photography is Nikon's unique 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 fast zoom lenses with maximum aperture, such as 17-35mm, 28-70mm and 80-200 mm, which enables these lenses to perform autofocus operation quickly and quietly, thus being suitable for shooting sports and operating scenes quickly. Nikon now 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 close-range correction (CRC) close-range focusing is a very needed function 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. D-type distance information D-type and G-type Nichols 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. DX 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 -ED lens is made by Nikon optical designer and Nikon lens expert. ED lens is 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. For details of G series lenses, please click here. IF internal focusing 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. Nano-crystalline coating technology Nikon has developed nano-crystalline coating, which is a new anti-reflective lens coating technology, which can reduce ghosts and spots, especially images taken under strong sunlight or light. The technology was developed as a by-product of Nikon NSR (Nikon Distribution and Repeat) semiconductor manufacturing system. Phase Fresnel (PF) Nanocrystalline Coating Seen through Microscope Nikon can make phase Fresnel (PF) lenses by using and relying on more advanced optical technology, thus making 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. Backward focusing 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-DC 135mm 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. Super ED lens Super ED lens is another new development of Nikon's own ED lens technology. Nikon optical designer and Nikon lens expert * * * developed the super ed lens, and its optical characteristics are similar to those of fluorite lens. 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 IF ED lens Super ED lens is not as easy to crack as fluorite lens, and its optical performance changes less 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 -SIC In order to improve the performance of its optical lens, Nikon adopted a unique multi-layer lens coating technology to reduce ghost images and light spots to a negligible degree. 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–Shock Absorbing System, an innovative system, can prevent image blurring 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. VR 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 Canon high-end EF lens terminology image stabilizer 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 (USM) 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. Carl zeiss and Sony are from West Germany, carl zeiss has advanced optical technology, and Sony will be an optical layman. With strong technical support, Sony has become a big name of consumer-grade DC. In recent years, Sony's SLR cameras have been 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 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 autofocus Zeiss brand lens produced at present. 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. Include: Sony α carl zeiss distagon t *1:2 24mm zassm [sal-24f2z] Sony α carl zeiss Planar t *1:1.485mm za [sal-85f14z]. Sony α carl zeiss Sonnar T *1:1.8135mm za [sal-135f18z] Sony α carl zeiss Vario-Sonnar T * dt1:3.5-/.