What does AS mean in Nikon lens?

emergency department

ED (ultra-low dispersion) is a very common symbol, which has been basically popularized in Nikon's mid-range and above lenses. Indicates that the lens made of ED glass is used in the lens. Because the visible light of different colors (red, blue, green, ...) is different, the refractive index after passing through the optical lens is also different, and it can't converge on the same plane position, especially on the telescope head with long focal length. The red and blue with short wavelength are easy to cause obvious dispersion, which is why the purple edge that puzzles many digital cameras comes from it. ED glass has the abnormal refractive index of colored light, so the light passing through the ED lens can still converge on the same point accurately, so it is called ultra-low dispersion. This material plays a great role in improving lens dispersion, brightness and sharpness, and color expression. ED lens can also be called one of Nikon's housekeeping skills.

sic

SIC (super-integrated coating and super-comprehensive coating), the significance of coating to the lens goes without saying, right? In order to better improve the color and optical performance, modern lenses generally adopt multi-layer coating, and even some coatings can reach as many as 10 layers (super EBC coating of some Fuji Dragon lenses), which is amazing. The lens coating is an antireflection film, which can change the reflection characteristics of the lens surface, make the light easier to transmit rather than reflect, and improve the color performance of the lens, such as the color of the lens is yellow. You only need to coat a film with antireflection effect on the blue color to make up for it. Nikon's coating technology is not among the three most advanced supermodels in the world, but its performance is still extraordinary. For example, the famous golden wide-angle Nicole 17-35/2.8ED, at least half of its anti-glare ability comes from excellent coating.

ordinary

There are many kinds of n. If you see n on an older lens, it probably means something new. However, in recent years, the N with the hexagonal bottom hollowed out on the new lens is Nikon's new technology, nano-crystalline clothes. The biggest function of this coating is to prevent the lens from reflecting light and increase transparency. For example, the new Nicole 105/2.8 micro uses this. By the way, because the surface reflection of CCD/CMOS is much more serious than that of film, many old lenses are used in digital cameras, and the image quality will be slightly reduced. Each factory has done two main tasks specifically for the optimization of digital cameras. One is to change the optical design of the lens to make the light incident vertically as much as possible, so that it will not exit even if it is reflected, and the imaging quality will not be too high. On the other hand, the solution is to coat the rear lens to inhibit the reflection of the lens surface.

active server pages

ASP (aspherical lens element) aspherical lens group is familiar to everyone, so the benefits of aspherical lens will not be listed one by one. Interestingly, Nikon said that its first lens using aspherical lenses was produced in 1968 (I vaguely remember it was a fisheye lens, but I forgot the parameters). However, as we all know, Nikon uses an aspherical lens, and the most famous lens is actually NOCT 58/ 1.2. Nikon is more kind to use aspherical lenses, and doesn't brag much. Unlike Pentax, which needs to be marked with an eye-catching al, Lycra can write an ASPH symbol for robbing money.

Cyclic redundancy test

CRC (Close-range Correction System) Close-range Correction System (CRC) is one of Nikon's most important focusing inventions, which can provide excellent image quality when focusing at close range and increasing the focus range. Using CRC system, the lenses will form a "floating lens" design, and each lens group will move independently when focusing, which can ensure the best optical performance even when shooting at close range. The most famous lens used in this system is AF28/1.4d. ..

if

Internal focus (IF), internal focus. This is a good explanation, that is, when focusing, the length of the lens body remains unchanged, while the lens moves inside the lens barrel to complete the focusing work. Generally speaking, lenses that require better sealing will adopt internal focusing design, which also makes the focusing speed faster (the moving distance of the lens is relatively short), and the representative works are AF 180/2.8ED.

Radio frequency (radio frequency)

After focusing (RF), focusing behind the mirror. This is a little different from the internal emphasis above. The main feature is that when focusing, the rear lens group moves and the front lens group does not rotate. This design facilitates the use of optical filters, especially polarizers or gradient lenses with directional restrictions. A typical example is af85/1.4d. ..

direct current

DC is the symbol of caustics control lens. At one time, major manufacturers were fascinated by the Jiao Wai blur effect of defocus control lenses, so they produced many such lenses, such as Nikon's AF 135/2DC and Minolta's housekeeping lens Minolta AF 135/2.8 [T4.5] STF.

D

D stands for distance information, distance information. This thing is not new at all, mainly because the lens can transmit distance information to the fuselage. In fact, the biggest function of this system is to cooperate with the flash to achieve more accurate flash compensation. Nikon SB28 is called the magic lamp because of its accurate fill light, and the D system is indispensable. Of course, it can also cooperate with Nikon's unique 3D matrix metering system.

G

G is the symbol of Nikon's new generation lens, but this symbol only means that there is no aperture ring, and the aperture is completely controlled by the fuselage. G-mirror can be compatible with cameras after F4, but cameras before that can't, including the famous F3 (without aperture ring, you can't transmit aperture information to the fuselage, use a P). Note that G-mirror only has no aperture ring, and there are apertures and aperture rods, so be sure to pay attention when describing it. It is wrong to say that the G-mirror is a lens without aperture.

Single white male

SWM is a silent wave motor. Do many people want to say that they have not seen this sign? Put it another way, you will understand. You've seen AF-S, right? This is the thing, Nikon's ultrasonic motor. Some people may wonder, ultrasonic motor doesn't seem to be a high technology, why did it come out in recent years? There is a simple reason. The patent protection period of ultrasonic motor originally applied by Canon is only 15 years. Just now, let's recall, when did the ultrasonic waves from other countries except Canon come out?

VR（Virtual Reality）

Vibration reduction (VR) eliminates vibration. I don't need to say more about VR. Nikon is proud of its anti-shake (vibration reduction) system, which has fast response and good effect. Unfortunately, lenses with VR are basically sky-high prices (the cheapest VR telephoto lens also has a good effect). Regarding the controversial anti-shake of fuselage or mirror, Bian Xiao just wants to make a metaphor to illustrate my personal opinion. When I was a child, everyone played a little trick, that is, reflecting sunlight to the wall (blackboard, ceiling, girls' faces, etc. ) with a mirror? You have to know that if the mirror moves a little at a small angle, the light spot will move a long distance, and that's the problem. If we want to keep the relative position of the light spot on the wall, is it more effective to stabilize the mirror or the wall?

mergers and acquisitions (M&A)

Manual/automatic mode. Let's talk about this matter. In the previous fuselage-driven nikkor lens, M/A stands for automatic manual switching. Nikon first made this mechanical device like Longteng SP90, which is sleeve push-pull type. Later, it made a circle to rotate and switch between manual and fuselage drive. However, the strength of this circle is somewhat insufficient, and many of them are broken during their service life. The third generation XGP is troubled by this trouble. There is an old version of AF 65438 in the lens used by Bian Xiao before. After the appearance of a large number of AFS lenses, Nikon gave this M/A a new meaning, that is, full-time manual focusing, which means that the focal length of the lens can be manually adjusted at any time whether it is in the state of body control focusing or not, which is very convenient, which is a huge progress for Nikon (although it has appeared on Canon EOS system for 10 years).

Advanced (short for deluxe)

DX Nicole. DX mirror is a series of special lenses specially designed for APS digital SLR cameras. Therefore, the image field is not large enough to be used in film cameras and full-frame digital SLR cameras, but the advantage is that the image quality is not low or even better, and it is also lighter, which meets the needs of low-end consumers. Nikon once blew DX into the future standard frame when there was no Quan Huafu, and even made the sky-high AFS 17-55/2.8 DX. Fortunately, after installing DX lens on D3, it will automatically switch to DX format mode, which can be regarded as comforting the injured mind of users.

Another version:

Nikon lens logo

Auto focus: auto focus

AI: Automatic indexing and automatic maximum aperture transfer technology, which is the process and method of transferring the maximum aperture value of a lens to a photometric system for normal exposure measurement.

Ai-s: automatic indexing shutter indexing technology.

SWM: silent Wabe motor ultrasonic motor, focusing quietly and quickly.

AF-S: autofocus driven by ultrasonic motor, where S is the representation of its ultrasonic motor SWM.

AF-I: The lens has a built-in motor, but it is not a lens with an ultrasonic motor.

G: Without a lens with an aperture ring, the aperture priority cannot be realized on Nikon's fuselage, and the aperture cannot be adjusted.

D: The lens with distance information can realize 3D matrix photometry, 3D multiple induction equalization and other functions to supplement the flash, making photometry and flash more accurate.

If: internal focusing, the first lens does not rotate when focusing, and the lens volume remains unchanged, which is suitable for installing filters.

RF: rear focus. When focusing, only the rear lens group will move to focus.

DC: defocus-image control Nikon defocus image control technology, generally used in portrait photography lens, can create a circular hazy effect outside the focus.

Ed: Ultra-low dispersion glass lens developed by ultra-low dispersion Nikon, which can reduce chromatic aberration and have good definition.

VR: the function of lens image stabilizer for vibration reduction Nikon. The speed of the safety shutter can be reduced by about 3 gears.

NIC: Nikon integrated coating Nikon multilayer coating.

Sic: super staggered coating Nikon SIC: super integrated coating, minimizing ghosts and light spots. It is an improvement on NIC.

ASP: Aspheric aspheric lens can remove coma and chromatic aberration of other different lenses.

CRC: Close-range correction system is Nikon's most important focusing invention, which can guarantee excellent lens performance even when shooting at close range.

DX: Nikon's lens specially designed for DX format, that is, its APS-C digital SLR, is equipped with a smaller image circle, which is smaller and lighter. But you can't use the whole picture, otherwise there will be obvious dark corners just now.

Nine: It is also a special lens for APS-C format.

M/A: Manual/autofocus manual/autofocus switching, full-time manual focusing.