Which wide-angle lens should I choose for Nikon? SLR cameras from this manufacturer can be divided into two groups. Models ranging from amateur cameras to the D500 have smaller APS-C image sensors (Nikon calls it DX), while cameras older than the D610 have full-frame (FX) sensors.
The selection of optics must be made in accordance with the sensor size, because a full-frame ultra-wide-angle lens will not provide the required angle of view on APS-C cameras.
The difference here is that you can use smaller DX format optics on lower resolution full frame FX cameras. It's not ideal, but if it was used on a DX model (eg a lens for example) and then the owner upgraded to FX, it should still be usable.
Sigma 10-20/3.5
This lens offers a brilliant combination of performance, technical characteristics and quality. Costs $399.99. It features a constant maximum aperture and no image stabilization.
It's newer, bigger and better than the original ultra-wides you can still buy, and not much more expensive than its predecessor. This is a professional, high-quality, high-aperture optic with a quiet annular ultrasonic zoom and a seven-blade diaphragm. The model is quite impressive and is equipped with a thread for a filter with a diameter of 82 mm. According to user reviews, its sharpness and contrast are excellent, uniform at all focal lengths. The color of the fringing is very well controlled, with distortion only becoming really noticeable at the short end of the range. This is a great lens for other small format models with an excellent price-quality ratio.
Sigma 8-16/4.5-5.6
Features an incredibly wide viewing angle and smooth autofocus with just 2x zoom and no filter ring.
Sigma 10-20/3.5 lenses are a bit like modern classics in terms of its specifications, performance and price, but if you need wider-angle optics, then you should still pay attention to this model. It only has a 2x zoom, but at such focal lengths the extra 2 mm gives huge difference in the angle of view. The lens is quite long because the hood is built into the body, but the build is very good and the zoom ring operates smoothly, as does the ultrasonic AF system. According to users, the only downside to the ultra-wide angle is the more noticeable barrel distortion at the lower end of the range, but as an optic that provides the most possible review, she has no equal.
Nikon AF-S DX 10-24/3.5-4.5G
Like other lenses suitable for Nikon, this model, compared to similar third-party optics, seems too expensive ($796.95). In its favor is the presence of a 2.4x zoom, the same as the Tamron 10-24mm, although the latter will cost almost half the price. But Nikon's build quality and design are excellent, with ultrasonic autofocus that makes setup fast, quiet and smooth, along with excellent handling. Image sharpness at the mid-aperture is no more impressive than most other competing lenses, but the manufacturer still maintains sharpness well wide open, and images remain sharp in the corners of the frame. Vignetting is also fairly well controlled.
Tokina AT-X Pro 12-28/4 DX
With a minimum of 12mm, this wide-angle lens for Nikon isn't quite as 'wide-angle' as most of its rivals, but it does offer a larger maximum zoom that gives it more versatility. It feels reliable and features the new SD-M silent AF based on the GMR (Giant Magnetoresistance) system. According to customer reviews, the optics still lacks a full-time manual mode, but you can quickly switch from manual to automatic focusing and vice versa using a switch on the lens. The amount of barrel distortion is disappointing minimum settings zoom, but at long focal lengths it is practically absent. The sharpness is respectable, although it is not as good as the Tokina 11-16 mm.
Tokina AT-X Pro 11-16/2.8 DX II
The comparatively paltry 1.45x zoom at both minimum and maximum focal lengths is unimpressive. But the specification that sets it apart from the rest is its widest f/2.8 aperture, which remains consistent across the entire range. This makes this one of the brightest on the market. An update to the previous model includes an AF motor, allowing it to be used with cheaper Nikon cameras such as the D3300 and D5500, which do not have built-in AF motors. Sharpness is good across the zoom range, although color fringing is a bit excessive and distortion levels are somewhat disappointing.
Full frame
Although the manufacturer's full-frame cameras allow the use of ultra-wide-angle DX format optics, this option is reserved for emergency situations, since the camera must operate in crop mode, losing more than half of its resolution. Therefore, owners should invest in good Nikon lenses that match the sensor size.
Nikon AF-S 14-24/2.8
This lens is impressive in size, but its performance is exceptional. Nikon's top-end ultra-wide-angle zoom is designed for full-length SLR cameras, and it is amazing with its characteristics. While the lens doesn't offer the widest field of view, it comes close, and does so with a constant maximum aperture of 2.8 and superb image quality, and, quite remarkably, remarkably low levels of distortion and aberration. Of course, this comes at a cost ($1,696.95), and not just financially. According to owners, the lens is not only expensive, it is also large and heavy, with a very convex front lens, which requires a fixed petal-shaped lens hood and prevents the use of conventional filters. Autofocus is incredibly fast - faster than all of its competitors.
Tamron 15-30/2.8
This lens is not as wide as the previous model, but it still has a wider field of view than most others. Tamron has developed a line of fast zoom optics with a constant wide aperture of f/2.8, and this model takes it into the ultra-wide field, continuing its tradition of impressive build quality, weather-resistant design, ultrasonic autofocus and image stabilization. It's a large lens, but it balances well on full-frame Nikon cameras. According to user reviews, sharpness is impeccable from the center to the very edge of the frame throughout the entire zoom range. The color of the edging is well controlled, vibration compensation gives a 4 stop advantage.
Nikon AF-S 16-35/4G
The first wide-angle lens for Nikon with optical stabilizer. It is based on the second generation of vibration reduction system and provides a four-stop advantage. The lens lacks the focal length range and maximum aperture of competing models, but has become a popular and lighter alternative for landscape photographers - especially since it can accept standard filters. Its other advantages include silent ultrasonic AF with full-time manual adjustment and a waterproof connection. According to owners, the image quality is good, although barrel distortion is very noticeable at 16 mm.
Nikon AF-S 18-35/3.5-4.5
This is a variable aperture lens that is smaller and cheaper than the 14-24mm and 16-35mm models. The user loses a little in the angle of view, and the variable maximum aperture is cheaper, which hints at the amateur audience. The lens does not suppress vibration, although overall the build quality is good. Another simplification is the integrated rather than nanocrystalline coating of the optics, although its resistance to ghosting and flare is still high. Owners report that chromatic aberration is well-controlled for a lens at this price point, and fine detail is captured very well, even at the edges of the image, although sharpness at the short end of the zoom range can't match the Nikon 16-35mm.
Sigma 12-24/4.5-5.6
This is the full frame equivalent of the APS-C Sigma 8-16mm format. With a 122-degree field of view at the shortest focal length, the lens surpasses anything available in full-frame SLR cameras Nikon without resorting to using a fisheye lens. There's ultrasonic ring AF and excellent center sharpness throughout the camera's zoom, although it falls off towards the corners of the frame when using wide apertures at short focal lengths. According to owners, barrel distortion is quite well controlled, although it is often weak point ultra-wide-angle optics. Variable aperture is not ideal, there is no image stabilizer, but if the maximum possible angle review is the main condition, then this lens should top the list of contenders.
Tokina AT-X 16-28/2.8
It's a heavy and large wide-angle lens for Nikon, weighing in at almost a kilogram, partly due to its constant f-number of 2.8. It has a quiet DC AF motor and a GMS module, which, according to the manufacturer, provides faster and quieter AF. This is certainly true compared to some older Tokina models. The optics are distinguished by the presence of a mechanism connected to a ring that serves to switch between manual and autofocus. According to the owners, this is very convenient, as it eliminates the need to manually set modes on the camera body or lens. According to users, control and image quality are very good, with high level sharpness in the center and subdued color fringing, although the corners could be sharper. The built-in lens hood helps avoid ghosting but eliminates the use of filters.
Nikon has produced a huge number of lenses today. Some of them can be recommended to everyone, but some I would not recommend to anyone. But today we are talking about the best lenses from Nikon. We will not take the most expensive lenses - there was a separate article about this..
10th place. Nikon 40mm f/2.8G AF-S DX Micro
So, 10th place is occupied by the only macro lens in our TOP. This is Nikon's most budget macro lens to date. It is only suitable for cropped cameras. This lens will give you the opportunity to get acquainted with macro photography for little money - that’s its main advantage. 
9th place. Nikon 24-85mm f/3.5-4.5G ED VR AF-S
This lens is essentially a kit lens for full-frame cameras. Considering the low price, especially if you buy it in a package with a camera, it legitimately ranks 9th on our list. As for the picture quality, you shouldn't expect miracles here: this is a lens entry level for a full frame camera. 
8th place. Nikon 18-55mm f/3.5-5.6G AF-S VR II
Essentially an analogue of 24-85mm, but for a crop camera. He took best place only because it costs much less. But don't think that this lens is bad. For a beginner, this is an excellent option that allows you not to spend a lot of money on additional lenses at first, while not limiting its owner in any way: you can shoot portraits, landscapes, and even light macro. 
7th place. Nikon 55-300mm f/4.5-5.6G ED DX VR AF-S
I reviewed this lens. It is suitable only for crop cameras and is inexpensive compared to its analogue for full frame(70-300mm). At the same time, its picture quality remains at a good level, and the lens itself, despite the budget, is made of quite high quality. 55-300mm is the kind of glass that is bought to complement the whale 18-55mm. And the lens copes with this task perfectly. 
6th place. Nikon 24-120mm f/4G ED VR AF-S
A lens designed for a full frame camera. Of course, like other lenses for FF, it can be used on a cropped camera, but this is not very convenient due to the insufficiently wide viewing angle at 24mm on a cropped camera. But at full frame this lens is quite versatile. Compared to the 24-85mm, it wins in all respects, but loses only in price. Nevertheless, the lens is very decent, which confirms its sixth place in our TOP. 
5th place. Nikon 50mm f/1.4G AF-S
Considering that this lens has an f/1.4 aperture, its price is not at all high. He only takes fifth place only because he has an alternative. We'll talk about it a little lower. Returning to the 50mm f/1.4, I would like to note the following advantages besides the price: beautiful bokeh, high-quality construction, modern design, built-in autofocus motor. 
4th place. Nikon 70-200mm f/4G ED VR AF-S
This lens would have ranked higher if not for its price. Moreover, before the exchange rate jumps, its price seemed quite reasonable. However, the 70-200mm f/4G is an excellent long focal length zoom lens with a constant f/4 aperture. It has simply excellent sharp images, not much inferior to the top-end 70-200mm f/2.8G. In addition, it is lightweight (for such a lens), has a high-quality image stabilizer and a chic design (this is already premium, no matter how you look at it). 
3rd place. Nikon 50mm f/1.8G AF-S
Here is an alternative to the fifty-kopeck piece that took fifth place. The 50mm f/1.8G is cheaper, and there are far fewer complaints about its autofocus performance. It just so happens that a more expensive lens is praised much less than its cheaper version. This lens is perfect as a universal prime lens for a full-frame camera. 
2nd place. Nikon 85mm f/1.8G AF-S
In my humble opinion, this lens is the best portrait lens for Nikon today in terms of price/quality ratio. Sharp and precise. Its potential is better revealed on full-frame cameras, but this lens can also show a lot on a cropped camera. 
1st place. Nikon 35mm f/1.8G AF-S DX
This
They allow you to focus on an object without making any physical effort in the form of “twist the focus ring” or “try to determine by eye whether the object is in focus.” With the advent of autofocus, the everyday life of a photographer has become much easier and more fun. Yes, many will not agree with me and will say that all the romance of the shooting process has disappeared, but oh well, let everyone who disagrees focus romantically with their hands.
Nikon began producing lenses and cameras with autofocus (AF hereinafter) already in 1986. All lenses that had AF were marked - AF (autofocus).
The AF operating mechanism is very simple, since in 1986 no one even dreamed of digital, autofocus was mechanical. The process was as simple as a door; a gearbox was installed on the lens:
and in the camera there is a drive:
The camera determines the required distance to the object, the drive rotates the gearbox and voila - autofocus. Popularly, this method of focusing is called “screwdriver”, i.e. There is a “screwdriver” in the camera.
Examples of cameras with a “screwdriver”: D50/D70/D80/D90 /D200/D300/D7000 /D7100 /D700 /D750 /D810 /D3
AF-S (Aftofocus silent/quiet autofocus). Lenses of this type appeared relatively recently. They focus much quieter (some almost silently) and much faster than AF lenses. The difference is that the drive is already in the lens, and the camera only sends signals through the contacts:
the drive is already adjusting optical design at the required distance. In general, it doesn’t matter how it’s done, but the result is fast and silent autofocus.
Now about the main thing, Nikon has made a division between its digital cameras for commercial purposes. What division?
But what, starting with the release of a budget SLR camera, all budget versions of Nikon DSLRs are produced only with AF-S focusing, i.e. they are all without a “screwdriver”, namely this: / /D60/D3000/ / / / /D5200 /D3300 /D5300 /D5500.Important: AF-S works on all Nikon digital cameras, so you don’t have to worry about autofocus, but for AF lenses to have autofocus
I often come across questions like “will this or that Nikon Nikkor lens fit my camera?” It so happened historically that all lenses from 1961 onwards can be installed on all Nikon cameras - be they SLR or digital. But every rule has its exceptions and snags.
About the possibility of installation on the camera - FX and DX
Nikon digital cutting cameras are divided into two types: FX and DX, depending on the size of the sensor. Lenses for these cameras are marked in the same way. FX lenses are designed for full frame FX cameras, DX lenses are designed for crop cameras. Nikon FX cameras have a matrix the size of a classic 35mm film, DX cameras have a smaller matrix, the so-called cropped one, with a frame diagonal 1.5 times smaller than in FX. About the difference between DX and FX in more detail in the section on crop factor.
Attention: in general case Nikon DX cameras are APS-C cameras and Nikon FX are APS cameras. Often, third-party manufacturers use APS-C and APS instead of the abbreviations DX, FX, since this is a more general concept.
Before the release of DX cameras, there were only full-frame Nikon FX lenses, which actually do not have the FX designation, since at that time there was no need to separate full frame and cropped. Examples of lenses from full-frame cameras:
Nikon AF Nikkor 85mm f/1.8D,
Nikon 70-300mm f/4.5-5.6G IF-ED AF-S VR Zoom-Nikkor,
Nikon 50mm f/1.4 AF-D NIKKOR
If the lens does not have a DX designation, it means it is from an FX camera.
After the release of DX digital SLR cameras, the manufacturer, to save on glass, iron and plastic, began producing DX lenses. And all crop lenses already had the DX designation. Examples of DX lenses:
Nikon 35mm f/1.8G AF-S DX Nikkor,
Nikon 18-105mm f/3.5-5.6G ED VR AF-S DX Nikkor,
Nikon 18-55mm f/3.5-5.6G ED II AF-S DX Zoom-Nikkor
As you can see, all lenses have the letters DX in their names.
Important about DX and FX
All Nikon FX lenses can be used on APS-C cameras with a crop sensor, such as D1, D2, D100, D200, D300(s), D70(s), D80, D90, D7000, D40(x), D60, D3000, D3100, D3200, D5000, D5100, etc.
All Nikon DX lenses can and are preferably used on APS-C cameras with a cropped matrix.
All Nikon DX lenses can be used on full-frame APS cameras such as Nikon D3, D3s, D3x, D4, D700, D800, D800E, but the camera will either use only part of its sensor to take the photo, or the resulting image will have irreparable vignetting. This is due to the fact that DX lenses cannot project the image onto the large sensor of FX cameras. The use of DX lenses on FX cameras is not recommended. Full frame cameras can automatically recognize a DX lens and configure itself to work with it. Personally, I don't see the point in buying an expensive full frame DSLR camera and using "simple" DX lenses on it.
For all Nikon FX cameras, it is recommended to use only FX lenses.
All full-frame lenses (lenses from FX cameras) can be used on DX cameras without any problems, you just need to take into account visual effect from the crop factor.
If we summarize the above points, then a small conclusion suggests itself - regular FX lenses can be used on all types of FX and DX cameras. And lenses from cropped DX cameras are not recommended for use on full-frame FX cameras.
DX and FX lenses
A small note, I did not call DX more “simple” out of malice. It just so happens that all professional optics from Nikon are full-frame lenses; the only professional lens for DX cameras is the Nikon 17-55mm f/2.8G IF-ED AF-S DX Zoom-Nikkor.
Attention: The DX lens does not indicate equivalent focal length, but the usual focal length for 35mm film. Focal length is a physical parameter of the lens itself, which does not change when installed on different cameras. For both FX and DX lenses, to find out the EGF for DX cameras, you need to multiply the focal length by the crop factor 1.5.
About the automatic focusing feature
The designations AF, AF-I, AF-S are responsible for the ability to automatically focus the lens on a Nikon camera.
What is the difference between AF-S and AF lenses? In an AF lens, focusing occurs due to the camera motor (they say that the camera has a screwdriver or a focusing motor); in AF-S, focusing occurs due to the lens motor. Therefore, when choosing a camera, see if it has a built-in focusing motor; it will allow you to work with both AF-S and AF optics. Below, in more detail.
AF lenses do not have a built-in autofocus module and will autofocus on cameras that have a focus motor.
The following Nikon digital SLR cameras can work with AF lenses in autofocus mode:
D50, D70, D70s, D80, D90, D100, D200, D300, D300s, D7000, D700, D800, D800E, D7000, D1, D1h, D1x, D2x, D2xs, D2h, D2hs, D3, D3x, D3s, D4. since they have a built-in focusing motor. An example of an AF lens is the Nikon 50mm F1.8D AF. In turn, this lens will not have the ability to automatically focus on Nikon D40, D40x, D60, D3000, D3100, D3200, D5000, D5100 cameras since they do not have a built-in focusing motor. It is often said that junior cameras from the Nikon line cannot use “serious optics” - this is a misconception. We are only talking about the fact that autofocus will not work, all other functions will work just as well. And with manual focusing, confirmation of successful focusing will be indicated by a green circle in the viewfinder, and Live View and the electronic rangefinder have not been canceled.
Lenses marked AF-S indicate that they already have a built-in focusing motor, and that these lenses will automatically focus on all Nikon cameras. Therefore, if you have one of the younger Nikon digital SLR cameras, then ideally only AF-S lenses are suitable for you. These include Nikon 50mm F1.8G AF-S. Often, on AF-S lenses you can also find the prefix SWM, which means Silent Wave Motor.
AF-I are very rare lenses, usually very expensive and long focal length. I've never held an AF-I, so I can't say anything more.
When choosing a lens, the most important parameters are its type (FX, DX) and focusing method. If you now know which FX or DX camera you have with or without a built-in focusing motor, then by choosing a lens based on just these two parameters you will get everything required functions for shooting.
About aperture control options
On Nikon lenses you can find another interesting designation G - a lens with such a letter means that you can only control the aperture directly from the camera, and there is simply no aperture control ring. G (Gelded) lenses are actually impossible to use with older film cameras, since the aperture will be permanently closed. Also, lenses with an aperture control ring (not G) can be used more flexibly for various types of photo research, for example, such as macro with a reversing adapter.
Myths: It is often said that there are D and G lenses, D with an aperture control ring, and G without an aperture ring. In fact, this is not so, the letter D (often referred to as AF-D) means that it is possible to convey the focusing distance to the subject to the camera - this makes it easier to calculate the flash power for the correct exposure. It so happened that almost all D lenses have an aperture control ring. It’s just that previously they didn’t designate the division into lenses with and without an aperture ring.
To use a non-G type lens in the same way as a G lens (control the aperture from the camera), you need to set the aperture control ring to the maximum F number value, usually F16, F22, F32 and switch the special switch on the lens. Typically, lenses are either G and AF-S or AF and D, but there are exceptions, for example Nikon 70-300mm f/4.0-5.6G AF Zoom-Nikkor - a very strange specimen that does not have an aperture control ring, but at the same time At the same time, there is an old screwdriver autofocus. But at the same time, there are no lenses designated AF-S and D.
The remaining letters in the lens names simply indicate the presence of some additional features. Consider the long name of the Nikon 18-200mm f/3.5-5.6G IF-ED AF-S DX VR Zoom-Nikkor lens
18-200mm is an indicator of the focal length limits of the lens. 18mm is the widest possible angle, 200mm is the narrowest possible angle.
f/3.5-5.6 is an indicator of the lens aperture limits. The maximum aperture of F3.5 is available at 18mm focal length; at 200mm only F5.6 is available. That is, this indicates that when zooming, the lens aperture changes.
G - the aperture can only be controlled from the camera. There is no aperture ring.
IF - Internal Focusing - a lens with internal focusing; when focusing, the front lens does not rotate or move back and forth. Important when using filters.
ED - Extra-low Dispersion Glass indicates that the lens uses special low-dispersion glass, which allows you to get a better picture
AF-S - the lens has a built-in focusing motor and any Nikon digital SLR camera can focus automatically
DX - the lens is designed for DX cameras; on FX cameras it will produce strong vignetting.
VR - Vibration Reduction - vibration suppression, which will allow you to use more long exposures. The effectiveness of VR is described in the instructions for the lens. I have already written about image stabilizers.
Zoom-Nikkor is just a beautiful attachment that says that it is a zoom lens. All lenses from Nikon are called Nikkor. In fact, Nikkor and Nikon are the same thing.
Likewise, just by the name of any lens you can glean a lot of useful information.
Conclusion
All modern Nikon lenses can be installed on all modern Nikon SLR and film cameras. But there are a number of functionality limitations that are described in the article.
Many people have heard about the “crop factor”, as well as DX cameras and FX cameras, but few understand what this means. In fact, there is nothing complicated about it.
There is a misconception that when using the same lens on FX and DX cameras, its focal length changes, and it must be multiplied or divided by the crop factor. This is all speculation of uneducated people, but first things first.
Historically, 35mm film (more precisely, its dimensions are 24x36mm) was and remains very popular. At the dawn of the digital age, Nikon wisely decided that it would be a good idea to make a digital camera so that it could screw on the old lenses that had been produced for decades.
The idea was good, but there were problems with implementation. It’s too expensive to make a full-frame sensor, and there’s no point in making a very small one. As a result, a “golden mean” was found - a sensor whose diagonal size was one and a half (1.5) times smaller than a 35mm film frame. 1.5 is the crop factor (“crop” in English means crop). By the way, Canon found the optimal solution in the form of a crop factor of 1.6. Nikon called the crop DX.
DX lenses appeared because the sensor area was reduced by more than 2 times and it was possible to save on the production of expensive optics, thereby making DX technology accessible to amateurs. Here is a visual picture of how much the sensor area has decreased:
The first rectangle is the 35mm film or FX sensor. The second is the DX sensor versus FX. The third is the 4:3 format, which is widely used Olympus, Panasonic, and many others. In the lower row are typical point-and-shoot sensors. For example, the lower right, which is 1/2.5″, in the popular model Canon A470 . The FX sensor, that is, full-frame, appeared relatively recently and completely matches the frame size of 35mm film and works perfectly with all old lenses.
Why is there such a zoo of sensors? It's all about the price. Even now, in the “age of NTR” (NTR – Scientific and Technical Revolution, my geography teacher said so, but no one could understand what it means), the production of an FX sensor costs about 20 times more than a DX. This is why FX cameras are so expensive.
But what, after all, do these sensors give us? In the case of Nikon, we get excellent compatibility with all Nikon lenses, save money, but what's the catch? The catch is that a lens with a focal length of 35mm, for example, on a DX camera will have a narrower angle of view than on an FX camera. This can be clearly seen in the title picture.
This is where confusion arises for many. The viewing angle on a DX camera is narrowed in such a way as if you were looking through a lens with a focal length of 1.5 times greater on an FX camera, that is, about 50mm. However, the focal length does not change! The viewing angle changes. That is, you need to cut out a piece of the picture from a 35mm frame. This will be what you see on the DX camera. And vice versa - if you are used to using a 50mm lens on a DX camera, screwing it on to an FX camera, the frame boundaries will seem to expand for you, and not the focal length will change. Changing the focal length is equivalent to zooming in/out on the subject, but you won't notice any of that. Here's an example:
I took 2 frames, and then combined them in Photoshop and highlighted them with brightness for clarity. One shot is in FX mode (35mm), the other is DX. As you can see, no change in focal length occurs.
In a nutshell, focal length is the distance from the center of the lens to the sensor. It is clear that it will not change if the lens is the same, and only the size of the sensor changes. Those who don’t understand it in words can watch the video:Confusion with focal length arises due to the fact that the illusion of proximity is created. After all, the cut piece from the frame is stretched across the entire screen. This is similar to “digital zoom”. You compare a 10x15 photo printed from a 35mm shot with a photo of the same size printed from a DX shot and the objects appear to be closer in the second print. Yes, they are closer, but not due to a change in focal length, but due to the fact that a piece of the frame was cut out and stretched to the size of a 35mm frame.
Why is it important that it is not the focal length that changes, but the viewing angle? Because focal length affects many things. For example, when the focal length changes, the depth of field. None of this happens if you remove the 50mm lens from DX and attach it to FX. Depth of field will remain the same. In addition, by changing the focal length, the composition of the frame will also change.
What is the use of FX, what do we pay money for? Thanks to large sizes, the sensor allows you to get rid of digital noise at high ISO. If noise is visible on a point-and-shoot camera at ISOs greater than 400, then on an FX camera you can hardly see it at ISO 3200. In low-light conditions, for example indoors, this is critically important and allows you to photograph without a flash.
All FX lenses work great on a DX camera. All DX lenses work great on an FX camera, but there is one caveat. If it is a Nikon lens, then the camera automatically switches to DX mode. If it is not Nikon, then you may need to manually switch through the camera menu. You can force disable DX mode, then you will get something like this.
