Overall Performance

The Nikon D600 is a very nimble and responsive camera with a wealth of external controls that put just about any shooting control you're ever likely to need a button-press away. You'll undoubtedly need to spend some time at the outset, however, configuring the camera's vast array of custom settings to your liking. Whether navigating through menu screens or using the command dials to change shooting parameters, you're never far off from being ready to capture an image. From power-on to first exposure with the camera in MF mode occurs in just under 0.3 seconds (approx) which is as good as instant, for any practical purpose.

Cycling among the 39 AF-area points can be done easily and quickly by 'feel' with the camera held to your eye in the shooting position. It should be noted, however, that the actual coverage of the D600's AF area is notably less than that of the D800, as we'll demonstrate further down this page.

Another area in which the D600 lags behind the D800 is its AF sensitivity in poor light. The D800 is rated for accurate focus in light as low as EV-2, which is approximately equivalent to moonlight. In use, we've found this to be true. The D600 is rated down to EV-1, and in normal use, with a 50mm F1.4 prime mounted, we've found that indeed, the D800 is the better tool in low light. But when shooting low-contrast targets at EV levels between 0-1, the difference between the two cameras is only noticeable at the point where we could barely perceive our subject in their viewfinders. The Canon EOS 6D has an AF system rated down to -3EV, and we will perform more in-depth comparisons between this and the D600 when the 6D becomes available.

In good light, the D600's AF system proved very capable in all of the environments in which we used it. In the hundreds of frames that we've shot with the camera, including images taken at night and in very poor interior lighting, only a handful are anything other than totally sharp. As usual, if you're working in marginal light the central AF point is your best bet, but in normal everyday shooting, the D600's AF system is very capable.

Continuous Shooting and Buffering

The D600 features dual SD card slots. You can specify either card slot as a primary storage source, with the remaining slot configured as overflow (default) or duplicate storage. When shooting in RAW+JPEG mode, you can also record raw files to card slot 1, with JPEGs recorded to slot 2.

As you'll see in the tables that follow, the number of images you can shoot with the D600 before filling its buffer varies according to the image quality settings. Crucially, you can still shoot single images as well as access all of the camera menus and shooting options while data is being written to the card. The D600 offers two drive modes; Continuous Hi and Continuous Lo. With a 5.5 fps speed in 'Hi' mode, the D600 bests the frame rate of the higher-resolution D800, falling just shy of the top speed of the 16MP D7000.

You can shoot the D600 in either a full-frame (FX) or 1.5x crop factor (DX) mode. Shooting in DX mode may be attractive for those who want significantly higher burst capacity and faster buffer-full rates, as you can see in the tables below.

For the timing tests below we used a Sandisk Extreme Pro 64GB Class 10 SD card (95MB/s). Active D-Lighting and lens distortion correction were disabled. Raw file output was set to the camera's default 14-bit, lossless compression settings.

FX Mode: Continuous Hi

JPEG Large/Fine
Frame rate 5.5 fps 5.5 fps 5.5 fps
Burst capacity 30 images 15 images 13 images
Buffer full rate 2.2 fps 1.5 fps max .85 fps
Write complete 25 sec. 14 sec. 17 sec.

DX mode: Continuous Hi

JPEG Large/Fine
Frame rate 5.5 fps 5.5 fps 5.5 fps
Burst capacity 100 images 30 images 20 images
Buffer full rate 4 fps 2 fps 1.5 fps max
Write complete 1 min, 8 sec. 27 sec. 16 sec.

Frame rates are consistent regardless of image quality or crop mode. The smaller DX format image files do allow for substantially higher burst capacity and increased frame rates once the camera buffer is full.

Continuous Lo at 3 fps: FX mode

The D600 gives you the option of specifying the maximum frame rate when the camera dial is set to Continuous Lo drive mode. It can be set between 1 and 5 fps ,topping out just shy of the rate for Continuous Hi. The table below shows results at the camera's default setting of 3 fps.

JPEG Large/Fine
Frame rate 3.0 fps 3.0 fps 3.0 fps
Burst capacity 100 images 20 images 16 images
Buffer full rate 2.2 fps 1.5 fps max .83 fps
Write complete 1 min, 8 sec. 19 sec. 20 sec.

As you can see, the only real benefit of shooting at a slower frame rate is that it allows longer shooting bursts at maximum speed.

Autofocus area

Of potentially significant concern for sports or wildlife shooters who shoot with Nikon's previous FX-format DSLRs is the size of the D600's AF area. Although the D600 is a full frame camera, Nikon has chosen to mate it with an AF system adapted that of the D7000, a DX format camera. As a result, the D600 has noticeably smaller coverage of the total scene area than its full frame siblings, the D4 and D800. This isn't unprecedented - the Canon EOS 6D offers an AF array smaller than Nikon's 51-point system too, for example, but it might fox someone who's simply become used to the focussing system in a D700 or D800 (or D4).

Superimposed over this image are the 39-point AF area region for the D600 and the larger 51-point counterpart found on the D800. The smaller coverage of the D600 won't matter most of the time but for some purposes - such as sports and wildlife photography, the smaller coverage could cause problems for someone used to working with one of Nikon's other high-end DSLRs.

In the (simulated) example shown here, the soccer player on the right, in the white jersey, is still largely covered by the wider AF array of the D800, but is almost beyond the reach of the D600's smaller AF area.

One way to minimize this limitation of course, is by shooting with the D600 set to its DX crop mode. This yields a very usable 10.5MP file and effectively allows the AF area to cover a significantly larger portion of the recordable scene. The point remains, however, that the D600's AF coverage is unusually small for a full frame DSLR and may indeed make the camera less appealing as a D800 backup for action shooters.

Something we've noticed when shooting in very low-light conditions is that focus acquisition is much more successful when using the central AF points. We've consistently seen instances where the AF points in the central 3 x 3 grid can lock focus quickly, yet attempting to focus on the same subject with outer AF points leads to focus hunt and ultimately a failure to confirm focus at all. We stress that this is limited to very low light situations and it's certainly not unreasonable to expect improved AF performance towards the center of the array. Shooters who work often in low light should be aware, however, that there are conditions under which these outer AF points will be of little practical use.

Sensor residue

An issue that has been reported widely on the web concerns the unusual frequency with which the D600 attracts dust and/or oil residue on its sensor, particularly in the upper left area of an image, which of course corresponds to the bottom right portion of the actual sensor. And sure enough, shortly after we received our review sample and began our studio testing we found we had to conduct a rudimentary non-invasive sensor cleaning.

In the first image below, debris is visible in the upper left corner even at this reduced thumbnail size. Click through to see a full resolution version which we've enhanced with an extreme contrast adjustment to make the debris more visible. We've paired the 'dirty' image with one taken using the same sensor immediately after being cleaned by a professional lens rental shop near our Seattle office*. As you can see, the difference before and after the cleaning is striking. Bear in mind that our D600 arrived new and at the time when we got its sensor professionally cleaned, we'd been shooting with the camera for only about four weeks, under conditions no different than our typical review process.

Sensor after normal use (~ 1 month) Sensor after professional cleaning

We can only speculate at this point as to the cause of the issue. What we can say is that simply blowing air did not remove all of the debris; a wet clean was required, suggesting that some contaminant may have found its way onto the sensor. We are of course, pursuing this issue with Nikon directly, and will update this review as more information comes to light.

* Our thanks to the lens rental department of Glazers Camera in Seattle.