Choosing the right NIKKOR Lens

Let’s start with format – the size of your camera’s image sensor. At 24x16mm, the Nikon DX-format is the smaller sensor, while the larger FX-format sensor measures 36x24mm, roughly the same size as 35mm film (which is why it’s sometimes referred to as ‘full frame’).

Different NIKKOR lenses are designed to accommodate these different sensor sizes. DX lenses (no prizes for guessing that they’re the ones with DX in their name) are optimised for use with the smaller DX sensor, and tend to be smaller and lighter than non-DX lenses. This not only keeps down the weight of your DX camera in use, but it also means DX lenses are cheaper to produce than non-DX lenses, since less material is used in their construction. FX lenses are designed for use on Nikon FX-format DSLRs cameras, and they don’t have DX (or FX, for that matter) in their names.

The DX’s smaller sensor covers a correspondingly smaller proportion of the image (around 44.44% of the FX sensor) projected by the lens, resulting in a 1.5x crop factor compared to what an FX camera’s sensor can cover. This means that a 24mm lens on a DX sensor camera will provide basically the same view as a 36mm lens (24mm x 1.5) on an FX camera. The larger FX sensor has a proportionately greater ‘light-gathering’ area, and offers higher sensitivity and generally lower noise, with no crop factor.

A DX-format camera can use both DX and FX lenses, but if you attach a DX lens to an FX camera, it will automatically select DX crop mode – recording an image only from the centre section of the sensor – to avoid vignetting, so the image will be magnified 1.5x times.

There are two basic types of lenses – primes and zooms. Prime lenses have a single fixed focal length, while zooms have variable focal lengths.

Using a zoom reduces the number of times you need to change lenses, which saves time and limits the chances of dust entering the camera. It also enables fast changes in perspective without you having to move an inch, which can be very handy for sports and candids. But the zoom’s main advantage is its versatility: it’s ideal when you’re shooting a range of subjects, such as landscapes and portraits, and you just want one lens to cover them all. A couple of zooms can do the job of a whole bag of primes, saving you money, as well as weight and bulk when you’re on the move.

Primes tend to be more compact and lightweight than zooms, as their construction is usually simpler, and that can also mean they’re a bit cheaper (although that’s not always the case!). They also tend to be ‘faster’ – having a larger maximum aperture (e.g. f/1.4 to f/2.8) that allows more light to hit the sensor. This is particularly helpful when shooting in low light, as it increases the possibility of hand-holding the camera and freezing the subject without shake or blur. That large aperture also means you can get a really shallow depth of field, which is handy for portraiture where you might want a softer or blurred background (‘bokeh’) to focus attention on your subject. And, because you physically have to walk into or step back from your subject when shooting with a prime, you might even find it prompts you to be more creative in your picture making.

Nikon’s current lens line-up is mostly autofocusing, with 10 lenses that are manual focus only. Of course, you can actually manually focus any autofocus NIKKOR lens, simply by setting it to the manual focus mode.

Manual focus NIKKORS focus silently, and they’re all fast primes. There are two main types of autofocus (AF) NIKKORs: AF and AF-S. An AF lens doesn’t have a built-in focus motor, which means the camera needs its own focus motor to utilise the lens’s AF capabilities. Nikon’s enthusiast and pro DSLRs (including the D7200, D750, D810, D4S and D5) all incorporate a focus motor. If you use an AF lens with a camera that doesn’t have one, you’ll have to manually focus the lens yourself. The electronic rangefinder – visible in the lower left of the viewfinder – will confirm when your subject is in focus by lighting up with a green dot.

An AF-S lens comes with Nikon’s exclusive Silent Wave Motor (SWM) built in. This enables the lens to control the focusing function, and results in faster and far quieter autofocusing. AF-S lenses can be used by any type of Nikon DSLR – both those without a built-in focus motor (consumer-level DSLRs such as the D5300 and D5500) and those with. Nikon has also just introduced AF-P lenses into its NIKKOR range, which use stepping motors to drive the autofocus for fast and quiet AF (these are already used in Nikon 1 system lenses).

• Here’s what those letters and numbers on the lens barrel mean…
• D – a D-type lens relays subject-to-camera-distance information to Nikon DSLRs with 3D Color Matrix Metering, 3D Matrix Metering, 3D Multi-Sensor Balanced Fill-Flash and i-TTL Balanced Fill-Flash. Many D-type lenses have an aperture ring, which is especially useful for adjusting aperture while recording D-movies .
• ED – an ED lens features Nikon’s ED (extra-low dispersion) glass, which corrects chromatic aberrations, yielding sharper images with better colour contrast.
• G – this indicates the lens doesn’t have an aperture ring, and therefore will be slightly lighter than an equivalent lens with an aperture ring.
• IF – this stands for internal focusing. Internally focused lenses don’t change length externally when you focus – all the activity is taking place inside the lens.
• MA/M – an MA or M switch on the side of the lens means you can go from autofocus to manual with virtually no time lag, and without changing any settings on the camera.
• N – this means the lens has Nikon’s Nano Crystal Coat, an incredibly effective anti-reflective coating (this minimises reflections, reducing ghosting and flare)
• VR – stands for Vibration Reduction, an image-stabilising technology that enables you to hand-hold several stops slower without causing blur, so it’s ideal for low-light shooting. Some VR lenses also have a Normal/Active switch, with Active designed for more unstable situations e.g. high winds.This is designed to offset just one specific axis of movement when the other is intentional (as might be found when shooting from a moving vehicle)
• VR II – indicates that this is the second generation of that particular lens, with enhanced VR capabalities usually one stop over its predecessor.
• 1:1, 1:2, 1:4 etc. – you’ll see these numbers on Micro-NIKKOR lenses, which are designed for close-up photography, and they indicate the reproduction ratio. 1:1 is life-size, 1:2 is half life-size, and so on.