The arrival of the Nikon D3 in 2007 heralded a new dawn for Nikon. As the company's first ever full-frame DSLR, the D3 offered a then class-leading sensitivity range up to the equivalent of ISO 25,600 – bringing with it all kinds of new possibilities for low-light photography. The enhanced sensitivity range was backed-up by a professional-grade build quality and flawless performance so it was hardly surprising that it soon became the go-to camera for many professional sports and news shooters. While 2010’s Nikon D3s – with its even greater ISO range of 102,400 – may have provided an update, the D4 takes the range into new territory altogether, improving the specification of the D3s in just about every area possible.
The Nikon D4 uses an all-new full-frame FX CMOS sensor that offers an effective resolution of 16.2MP – a sizeable improvement over the 12.1MP of the D3/D3s. Compared to other professional-grade DSLRs such as the 18.2MP Canon 1 D X, or indeed Nikon’s own 36.3MP D800 and 24.3MP D600 models the D4’s sensor might initially seem a little bit underpowered. However, for professional news and sports photographers working on-location the need is more for a camera that’s as reliable at ISO 6400 as it is at ISO 200 than it is about being able to blow images up to billboard proportions. In other words, the light-gathering capabilities of the sensor and how it performs in testing conditions are what really count.
In addition to the new sensor the D4 also gets Nikon’s latest generation of EXPEED 3 image processor. This offers 14-bit A/D conversion and 16-bit image processing and, combined with the new sensor, is able to provide the D4 with a standard ISO range of 100-12,800. This can be further expanded up to ISO 204,800 – something only the Canon EOS-1D X can match.
The D4 is capable of shooting full-res images at a maximum continuous shooting speed of 11fps, although to retain full control over AF and exposure control this drops to 10fps. The shutter has been redesigned too, with the resultant Kevlar/carbon fibre-composite unit tested to 400,000 releases – 100,000 more than the D3s.
Internally, there's a new 91,000-pixel metering system that takes the place of the 1005-pixel module used in previous flagship Nikon DSLRs. This works in tandem with Nikon's Advanced Scene Recognition System to calculate not only the correct metering values, but also to manage white balance, flash exposure, Active D-lighting and the AF system.
The Multi-CAM3500FX autofocus system that was introduced for the D3 has also been updated. The new system keeps the same 51-point AF arrangement, however the central 15 cross-type AF sensors are now sensitive up to f/8, which will doubtless be useful for wildlife photographers using teleconverters and long telephoto lenses. Nikon also claims that the D4’s AF system is faster than the D3’s and much more accurate in low light too, with the ability to focus right down to -2EV, which essentially means moonlight.
On the back of the camera the rear LCD monitor has been slightly enlarged to 3.2in (from 3in), and although resolution remains at 921k-dots the colour gamut is now close to the sRGB colour space for more accurate representation of colours. In addition, the screen is shielded by an anti-reflective coating. Should you prefer – and many users most certainly will – to use the optical viewfinder then the D4's provides 100% coverage with a magnification of 0.7x.
In terms of HD movie recording the D4 greatly improves on the (720p @ 30fps) capabilities of the D3s with 1080p movie capture at 30/25/24fps using H.264 compression. Should you want to create slow-motion movies then there’s also the option to record 720p HD footage at 60/50fps. In addition, there are three movie crop modes: FX, DX (1.5x) and 2.7x (native 1920 x 1080). ON the side of the camera you’ll find a dedicated ‘microphone in’ jack, with the camera offering 20 individual audio level settings. Next to this is a headphones socket that you can use to monitor sound levels in real time with. Should you want to you can also output the D4's uncompressed live feed to a suitable storage device via the HDMI connection.
Adding to its excellent all-round connectivity the D4 also gets an Ethernet port, which makes it possible to transmit images directly from the camera via a wired connection. Should you want to go wireless then you’ll need to purchase the optional WT-5 WiFi transmitter (£500) that screws onto the side of the body. With this dongle attached it's possible to control the camera via an iPhone, iPad or computer with a live feed of what the camera sees beamed direct to whatever device you’ve got it hooked up to.
The D4 is powered by a 2000mAh (10.8V) EN-EL18 proprietary battery. It’s important to note that this is a new battery that uses a different connector layout from the battery used by the D3 and D3s – in other words D3/D3s owners won’t be able to mix and match their battery collection. Nikon branded EN-EL18 replacements/spares cost around £110 at present.
For storage purposes the D4 is treated to twin memory card slots: one for XQD cards (the only DSLR on the to offer this option at present) and the other for CompactFlash. Seen as the natural successor to CompactFlash, XQD cards offer super-fast write speeds of up to 168MB/s and can presently store up to 64GB of data. The D4’s twin slots offer plenty of flexibility and can be set up in a variety of ways, for example with one acting as an overflow to the other, or with one recording JPEGs and the other Raw files, or even with one recording stills and the other storing video.