IQ: D600 vs D800

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Low light image quality

The D600 uses the same sensor (albeit placed in front of a different image processing engine) to that found in theSony Alpha SLT-A99. As you can see from the various test pages scattered through this review, it offers very good image quality in a range of different situations, including subdued and poor light. The examples on this page are intended to show in-depth, just what the D600's sensor can do, and how you can get the most out of its JPEG and Raw output for the best results at high ISO settings, in marginal lighting conditions. Note that we will replace or augment some of the examples on this page with comparisons against the not-yet-available Canon EOS 6D at the earliest opportunity.

Real-world samples (JPEG)

The D600 matches or exceeds its nearest competition in terms of pixel count, and easily offers among the best image quality, too. Even when the light drops and you reach for the highest ISO settings, JPEG and Raw files contain plenty of detail, and it is only above ISO 6400 (the D600's highest 'standard' ISO sensitivity setting) that noise really becomes an issue for practical purposes. As you can see from the images on this page, and in our samples galleries, we've come a long way in the past few years. We'd have no qualms setting out to shoot night-time street scenes with the D600 handheld at ISO 6400. As always, you'll get the best results by shooting and carefully processing .NEF Raw files, but JPEGs are eminently usable.

ISO 1600 - JPEG, artificial light100% crop
ISO 1400 - JPEG, artificial light100% crop
ISO 6400 - JPEG, mixed daylight/artificial100% crop
ISO 6400 - JPEG, artificial light100% crop

The images here weren't taken at high ISO settings in order to specifically see what the camera could do, they were taken at these settings because it wasnecessaryin the specific situations in which we found ourselves. Image quality is very high even at ISO 6400, and although not as sharp at 100% as we'd expect from JPEGs taken at lower ISO sensitivity settings, overall image quality is very impressive. There's no banding in these shots, and although noise is visible at ISO 6400, it's unobtrusive. The D600's AWB system has done well in all three cases, as well.

Noise-reduction (JPEG NR settings versus Raw)

If you're a JPEG shooter, you've got no option but to leave noise reduction to the camera itself, but you do still get a degree of control over how the D600 deals with high ISO noise - you can adjust it in four steps, from 'Off' to 'High'. The following example should give you an idea of the difference between these settings in normal use.

We set this scene up under very low tungsten light, and shot it at all five of the D600's noise-reduction settings in JPEG mode at ISO 12,800, and once more in Raw. White balance was set manually, from a gray card.

We processed the Raw file 'to taste' in ACR 7.3 to give you an idea of the difference between tweaking JPEG parameters and carefully processing Raw output.

NR Off - 100% Crop (detail)100% Crop (shadow)
NR Low - 100% Crop (detail)100% Crop (shadow)
NR Normal - 100% Crop (detail)100% Crop (shadow)
NR High - 100% Crop (detail)100% Crop (shadow)
Raw - processed in ACR 7.3 beta (detail)100% Crop (shadow)

The images above show precisely what we'd expect - at high ISO sensitivity settings, turning the D600's JPEG high ISO noise reduction down to 'low' or 'normal' gives grittier results, which are sharper when examined critically, but the trade-off is relatively high levels of luminance noise, and some speckles of blue chroma noise - especially in shadow areas. Under warm tungsten light, blue, speckly shadows are a real risk, and can look very unpleasant and unnatural. The 'Normal' level of noise reduction, which is set by default, is a good compromise between sharpness and noise reduction, but 'High' reduces luminance noise at the expense of fine detail, limiting sharpness when compared to the results when NR is turned to 'low' or 'off'. On the plus side, the more intense chroma noise reduction has neutralized the blue noise in the shadows, but has reduced color saturation in the rest of the image in the process.

None of the JPEG noise reduction settings can compare to a carefully processed Raw file though, and if you're prepared to spend a little time adjusting the various parameters (we're using a beta version of Adobe Camera Raw 7.3 in this case) you'll be rewarded with higher resolution, more natural-looking detail and cleaner shadow areas.

D600 versus D800 in low light (JPEG)

For this test, we wanted to see how the D600 and D800 compare at identical (default) JPEG settings. For ease of comparison, we've reduced the D800's 36MP output to 24MP, to match the D600. This allows us to get a good idea of how the two cameras compare at an equal output size, such as a large print. If you're curious about what the original D800 files look like before downsampling, click on the magnifying glass icons on the thumbnails below (original image will open in a new tab).

We set this scene up under very low tungsten light, and shot it using both the D600 and the D800. Exposure settings and shooting parameters were identical with both cameras, and white balance was set manually, using a gray card.

Click on the magnifying glass symbol on the images below for the full-sized (un-resized, in the case of the D800) originals.
D600D800 (resampled to 24MP)
ISO 3200 - 100% CropISO 3200 - 100% Crop
ISO 6400 - 100% CropISO 6400 - 100% Crop
ISO 12800 - 100% CropISO 12800 - 100% Crop

We're downscaling the D800's files to 24MP here, so it's no surprised that at a pixel level, the D800's JPEG output looks fractionally sharper than the D600. Also interesting to note though is that beyond ISO 3200, the difference in detail reproduction between the D600 and downsampled D800 images is fractional. The D800 clearly contains more detail at ISO 3200 but at ISO 6400 - and certainly by ISO 12800 - detail capture is all but identical even at very close examination. This isn't a huge surprise - the camera with the most pixels will always outresolve the one with fewer in ideal conditions, but at a certain point, noise will get in the way until there's little real benefit to be had from the extra pixel count.

D600 versus D800 in low light (Raw - no NR)

Here's exactly the same scene, showing comparative image quality in Raw mode at ISO 12800. Again, we've downsampled the D800 to 24MP, to match the D600 and again, we've provided a link to the full-sized original image for download. We've also provided a link to the original .NEF Raw files from both cameras. Note that we're presenting these images with zero sharpening, and noise reduction turned down to '0' in Adobe Camera Raw 7.3 (beta).

D600 - ISO 12800, Raw (No NR)D800 - ISO 12800, Raw (No NR)
100% Crop100% Crop

The story when we examine the D600's Raw output alongside the D800 is basically the same as it is for JPEG. The two cameras are very very similar when examined in this way. The D800 gives sharper images when downsized to 24MP from its native 36MP, which could mean fractionally better print quality in large prints, but the difference is small.

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