Nikon D2Xs Image Quality

Resolution
High resolution, 1,900 lines of strong detail.

Our laboratory resolution chart revealed distinct line patterns down to about 1,900 lines per picture height, though you could perhaps argue for close to 2,000 lines horizontally. Extinction didn't occur until well past the 2,000 line point, about 2,600 lines horizontally, 2400 lines vertically, as seen on our 2x resolution target shot (all numbers there refer to 1/2 the actual resolution, as the chart is shot at half-size). Use these numbers to compare with other cameras of similar resolution, or use them to see just what higher resolution can mean in terms of potential detail.

See full set of test images with explanations
See thumbnails of all test and gallery images

Sharpness & Detail
Reasonably sharp images overall, with good definition. Minor edge-enhancement on high-contrast subjects and minimal noise suppression in the shadows.

The Nikon D2Xs captures a great deal of fine detail, but its very conservative in-camera sharpening gives its images a somewhat soft look straight from the camera. The upside of this though, is that there's little or no loss of fine detail to the sharpening process, and its images take strong/tight sharpening in post processing very well. (For instance, try Adobe Photoshop's Unsharp Masking with settings of 0.3 pixel radius and 300%.)

Noise-suppression systems in digital cameras tend to flatten-out detail in areas of subtle contrast. The effects can often be seen in shots of human hair, where the individual strands are lost and an almost "watercolor" look appears. The crop above right shows only a tiny amount of noise suppression in the mid shadows, though the darker shadow areas do have limited detail. Still, good definition of individual strands.

Saturation & Hue Accuracy
Accurate color overall, though some oversaturation in strong blues and some reds, and slight undersaturation elsewhere. Still, generally good color with pleasing results throughout the range.

Most consumer digital cameras produce color that's more highly saturated (more intense) than found in the original subjects. This is simply because most people like their color a bit brighter than life. Like most pro DSLRs, the Nikon D2Xs renders colors much more accurately, showing almost dead-on hue and saturation, with only minor oversaturation of reds and some blues. Some strong greens and yellows are slightly undersaturated, but the deviation from 100% accuracy is very minor. Where oversaturation is most problematic is on Caucasian skin tones, as it's very easy for these "memory colors" to be seen as too bright, too pink, too yellow, etc. Here, the D2Xs performed well, though in some cases skin tones just slightly pink or warm. Still, the results were quite pleasing, and very close to absolute accuracy.

The other important part of color rendition is hue accuracy. Hue is "what color" the color is. The Nikon D2Xs again did very well here, with only very minor hue shifts in some reds, blues, cyans, and greens. Average color deviation was only 4.6 delta-E units, easily placing the D2Xs in the top rank of cameras we've tested.

Exposure and White Balance

Indoors, incandescent lighting
Very good color with the Manual and 2,650K white balance settings, just slightly cool and flat. Less positive exposure compensation required than usual.

Color balance indoors under household incandescent lighting was pretty warm with both the Auto and Incandescent white balance settings, though the Manual and 2,650K options produced very good results. Both were slightly magenta and a tad cool-looking, so we chose the 2,650K option, which was the warmer of the two. It's entirely reasonable for a pro DSLR to show a warm color balance on this shot when in Incandescent white balance mode. Such cameras are set to expect a 3200K white point in Incandescent mode, matching professional studio lighting. The household incandescent light source used here is much warmer-hued, at a color temperature of ~2600K. We would like to see better performance in Auto white balance mode, however.

The Nikon D2Xs required slightly less than the average amount of positive exposure compensation here, at +0.7 EV. Though overall color is a little pale and flat when compared to consumer cameras, the D2Xs' rendering is more true to the original subject, and hue accuracy is surprisingly good, with only slight purplish tints in the blue flowers. (Many digital cameras reproduce these flowers with a dark, purplish tint, so the D2Xs did quite well here.) Our test lighting for this shot is a mixture of 60 and 100 watt household incandescent bulbs, a rather yellow light source, but a very common one in typical home settings here in the U.S.

Outdoors, daylight
Accurate, though slightly flat color overall. Pretty good exposure as well, though high contrast under harsh lighting.

Outdoors, the Nikon D2Xs responded to harsh sunlight with slightly high contrast and slightly less saturated color. (Although the latter is probably simply a reflection of the D2Xs' bias towards color accuracy, rather than "punch.") Consistent with the indoor shots, the D2Xs typically required less than the average amount of positive exposure compensation however, and held onto a good level of detail in the shadows (though some noise suppression limits shadow detail).

See full set of test images with explanations
See thumbnails of all test and gallery images

ISO & Noise Performance
Very low noise at the low and moderate ISO settings, with very good results up to about ISO 400. Very smooth images, but significant loss of fine detail from ISO 800 on though.

Noise levels are low to moderate at the Nikon D2Xs' lower sensitivity settings, with excellent results to about ISO 400. At ISOs 800 and 1,600, noise levels are relatively low, but at the cost of significant blurring in areas of subtle contrast. At ISO 3,200, noise is quite high, with a significant loss of fine detail and a very strong grain pattern. Saturation also drops noticeably at high ISO settings.

The shots above are somewhat of an acid test for image noise, as the incandescent light source really emphasizes blue-channel noise. Performance under daylight-balanced lighting does still show the same overall behavior as above though, as shown by the crops below from our still-life shots.

In the crops from the Still Life shot shown above, we can see the D2Xs making its trade-offs between noise, subject detail, and color saturation. At low ISO, the camera does well in all three areas, up to perhaps ISO 400. At ISO 800 though, subtle subject details are flattened out, most noticeably in reds and other warm-hued colors, but to some extent across the spectrum. This approach does succeed in holding noise levels in check in areas of flat tint however. Images shot at the "unofficial" ISO of 1,600 (marked only as "H 1" in the camera's readouts) are still quite noise-free, but at the cost of significant subject detail in areas of subtle contrast. Color saturation decreases somewhat at ISO 800 and 1,600 as well. Finally, at ISO 3,200 (marked only as "H 2" in the camera's readouts), color saturation declines further, fine detail is largely gone, and noise in flat tints is quite pronounced. Bottom line, shots taken at ISO 1,600 make very nice-looking 8x10 inch prints, but with some loss of detail in areas of subtle contrast, and slightly lower saturation overall.

Extremes: Sunlit and low light tests
High resolution with strong overall detail, but high contrast and slightly limited shadow detail. Good low-light performance, capable of capturing bright images under average city street lighting as well as near darkness.

Sunlight:
Because digital cameras are more like slide film than negative film (in that they tend to have a more limited tonal range), we test them in the harshest situations to see how they handle scenes with bright highlights and dark shadows, as well as what kind of sensitivity they have in low light. The shot above is designed to mimic the very harsh, contrasty effect of direct noonday sunlight, a very tough challenge for most digital cameras. (You can read details of this test here.)

The Nikon D2Xs produced high contrast under the harsh lighting of the test above, tending to lose highlight detail a little early, but preserving very good detail in the shadows. Some noise suppression is visible in the shadows as well, which accounts for most of the relatively small loss of detail there. Though some areas look a little dark at +0.3 EV, I preferred it to the image at +0.7 EV, which had too many blown highlights for my preference, particularly in Marti's face. A pro would likely prefer the default exposure, which held onto almost all the highlight detail, albeit at the cost of a rather dark image overall. (Actually, a pro photographer would use some fill illumination on a shot like this, unless there was no other alternative, as in many photojournalism or sports settings.)

One side note on the above shots: I shot them with the Nikkor 18-70mm DX lens, which is quite sharp when stopped down to f/7.1 where these shots were taken. Despite my best efforts though (putting a focus sensor right on Marti's forehead/hair, then reframing to take the shot), the D2Xs consistently back-focused a bit here, putting the skin of her neck in sharp focus, and throwing her face slightly out of focus. I also found this somewhat the case on the Indoor shots, where I used a part of the flower bouquet as the focal point to get around it. We didn't have any problem with the 100mm lens we used for most of the studio shots, but it's possible that either the camera or our 18-70mm lens needed to be tweaked by Nikon service.

Low light:
The Nikon D2Xs captured bright images down to the darkest light level we test at (about 1/16 as bright as average city street lighting at night), at all of the ISO settings. Some of the dimmer exposures resulted in a slightly magenta color cast with the Auto white balance setting, but overall color is still pretty good. The camera's autofocus system was able to focus on the subject down to below the 1/16 foot-candle light level unassisted, an impressive performance, and one that's in synch with the exposure system. Do keep in mind though, that the very long shutter times necessary here absolutely demand the use of a tripod or other camera support to get sharp photos. (A useful trick is to just prop the camera on a convenient surface, and use its self-timer to release the shutter. This avoids any jiggling from your finger pressing the shutter button, and can work quite well when you don't have a tripod handy.)

NOTE: This low light test is conducted with a stationary subject, and the camera mounted on a sturdy tripod. Most digital cameras will fail miserably when faced with a moving subject in dim lighting. (For example, a child's ballet recital or a holiday pageant in a gymnasium.)

Print Quality
Excellent print quality, great color, prints as large as 13x19 are quite sharp, particularly with a little post-capture sharpening in Photoshop. ISO 1600 images lose a little subtle detail, but are still sharp in higher-contrast areas, and surprisingly clean to boot.

Testing hundreds of digital cameras, we've found that you can only tell just so much about a camera's image quality by viewing its images on-screen. Ultimately, there's no substitute for printing a lot of images and examining them closely. For this reason, we now routinely print sample images from the cameras we test on our Canon i9900 studio printer, and on the Canon iP5200 here in the office. (See the Canon i9900 review for details on that model.)

Images from the Nikon D2Xs hold together exceptionally well at large output sizes, with very little tendency to break up and display visible pixels as the output size is cranked up. With just a little judicious sharpening in Photoshop, 13x19 prints can be quite crisp, and even 20x30 inch prints can be surprisingly sharp looking.

Color-wise, the Nikon D2Xs is a model of appeal and accuracy. It shows slight oversaturation in reds and some blues, but the overall accuracy is really excellent, among the best we've seen.