Because of the NX10's rather aggressive default sharpening (see subsequent slides), clean, small detail areas look very good and noise-free up through ISO 400. You can clearly spot where the noise reduction steps up at ISO 800, where softness increases and there's a noticeable white balance shift. ISO 1,600 and up are pretty comparable to the rest of its class; usable for some scenes and small sizes, but generally best avoided.
It's notable that the NX10 delivered exceptionally low numbers on our noise tests, and the photos of the Color Checker charts at the various sensitivities used to derive the numbers do look very good. While it's usually true that high ISO sensitivity photos exhibit less noise in sufficient light than in low light, I've never seen quite as dramatic a gap as with the NX10. So if you need high sensitivities to be able to get faster shutter speeds in bright light, the NX10 fares quite well. But that doesn't translate to great high ISO shots in low light.
While a photo's fine details look OK at middle ISO sensitivities, it's generally because in its default settings Samsung applies excessive sharpening. As a side effect, though, artifacts get exacerbated in areas that might otherwise exhibit little noise. For example, note the very visible color noise and the blotchy luminance noise patterns here.
(1/125 sec, f8, evaluative metering, tungsten white balance, ISO 400, 18-55mm lens at 45mm, default JPEG settings)
While the camera preserves color saturation at high ISO sensitivities, you can see a lot of color noise and clipping in the shadows. And I couldn't get a better result out of the raw file using Samsung's custom version of SilkyPix (as of posting, Adobe had not yet added NX10 support in Camera Raw).
The NX10's default oversharpening becomes apparent in situations such as like this. In the top version, using the camera's default settings, you can see how sharpening brought out excessive crunchiness in the photos. I processed the raw version (bottom) in the bundled version of Silkypix, and by switching to the Natural setting got a much better result.
(1/80, f5.6, ISO 100, evaluative metering, AWB, 18-55mm lens at 55mm)
At 50mm, the 50-200mm lens displays a little barrel distortion--not a lot, but more than one expects to see at 50mm.
(1/100, f18, ISO 100, evaluative metering, AWB, default Picture Wizard setting, 18-55mm lens at 18mm)
Although the 30mm and 18-55mm lenses are pretty clean with respect to aberration, the 50-200mm displays some fringing at the edges of the frame. In-camera JPEG processing seems to clean it up automatically; it didn't appear in the JPEG versions of this photo but did in the raw (shown).
Also note that sensor cleaning on start-up is disabled by default. It only became an issue when I noticed this dark spot in the sky in several shots, which turned out to be a piece of schmutz on the sensor rather than a UFO. Enabling the cleaning cleared it right up. However, it not only operates when you turn the camera on, but every time it comes out of standby mode as well.
The NX10's color settings (dubbed Picture Wizard) are a bit of a mystery. On one hand, in this series of shots, Calm delivers the most accurate rendering, albeit a little flat, while the defaults boost saturation (and possibly contrast) until the color is borderline wrong. However, on our test shots of a Color Checker under daylight-balanced lights, the default settings produced relatively accurate colors and the Calm setting yielded extremely low-contrast and generally poor results. The bundled raw software doesn't provide analogous profiles to the ones in-camera making it difficult to match (the closest it comes is something called Super Neutral).