The D610, as with the D600, uses a sensor similar to the one found in the Sony Alpha SLT-A99, but with a different image processing engine. At 24.3MP, the D610 is among the highest resolution full-frame DSLR's on the market, only the D800 and Sony a7R are higher. It produces very good image quality across a range of situations, including low-light.
Like the D600, image quality from the D610 is impressive through the ISO sensitivity range of 100-6400. At high ISOs, the D610's full-frame CMOS sensor does a good job of retaining fine detail while minimizing chroma and luminance noise. The default JPEG settings of the D610 produces files that tend to have a natural, gritty look, avoiding edge halos from over sharpening or aggressive smearing at the highest settings.
|ISO 1600 - JPEG, mixed daylight/artificial|
In the above, straight out of camera, example, shot at 1600 ISO with the 24-85mm F3.5-4.5 lens, the D610 does an impressive job of maintaining a high level of fine detail with very little chroma noise in the shadows while producing natural looking colors. The auto white balance system also nicely balances the natural light coming in through the glass ceiling with the artificial lights found on each desk.
|ISO 2500 - JPEG, artificial light||100% crop|
|ISO 6400 - JPEG, artificial light||100% crop|
|ISO 12800 - JPEG, artificial light||100% crop|
|ISO 25600 - JPEG, artificial light||100% crop|
Even when shooting at the very highest ISO settings, the D610 delivers files that contain plenty of usable detail. Only higher than the standard ISO sensitivity setting of 6400 does noise start to become a practical issue in overall image quality. In the above ISO 12800 example (ISO boost setting "H1.0"), noise is noticeable, but still well controlled. When viewing the image at 100%, you can see edge sharpness getting muddy, however signs under the florescent lights of the market can still be easily read. At the D610's ISO ceiling of 25600, shadow noise is clearly visible, but the pattern is more film-grain without a lot of smearing. There's enough detail to be usable if needed for a certain look or situation.
Obviously, shooting in Raw mode gives you better control over white balance, noise reduction and highlight or shadow details that can be lost in JPEGs. The example below shows how much shadow detail can be recovered from the D610's 14-bit Raw files.
|JPEG - ISO 400||Raw + ACR 8.3 with tweaks|
In the above example, the foreground is in deep shadow and you can't see much detail in the construction equipment. I wanted less of a silhouette, so I processed the Raw in ACR 8.3 by lifting shadows +80, added a touch of warmth to the white balance and applied some noise reduction. As you can see, the D610's Raw files contain a lot of detail that can be pulled out, even when you think there is none.
The D610's built-in pop-up flash has a guide number of approximately 12/39 (m/ft, at ISO 100) and provides a 24 mm lens angle of coverage with a sync speed of 1/200 sec. Flash compensation is available in -3 to +1 EV increments of 1/3 or 1/2 EV. Just like the D800, the D610's built-in flash allows full Commander mode functionality for operating off-camera Nikon Speedlights. It can wirelessly control a single group or two independent groups of remote lights, and serve as a master flash. This is something to consider if using external strobes is your niche, since Nikon's own Df and the recent Sony a7 and a7R do not have this built-in functionality.
In addition to Commander mode functionality, the D610's built-in flash can also be useful for quick fill-light. This was shot with -.7 flash compensation using the 24-85mm F3.5-4.5 kit lens.
Overall image quality
As expected and like the D600, the D610's overall image quality is top notch. Despite featuring an AA filter, unlike some recent cameras such as the D5300, the 24MP full-frame sensor delivers impressive detail, even in low-light conditions.
We have no hesitation in using ISO sensitivities up to 6400. Even when boosting ISO above the base ceiling, we knew the camera would be capturing enough detail to be usable for our taste -- especially when shooting Raw files. JPEGs out of the camera are excellent and have a natural, unprocessed look.
The D610's metering system also produces well-exposed images in a variety of lighting scenarios. The auto white balance system is on par with other Nikon DSLRs, delivering consistent results in most conditions. However, when shooting people under artificial lights, it's still best to set a custom white balance setting for most accurate color.
Since the D610 has the same exact sensor as the D600, read our original D600 review for a more detailed image analysis. Overall, we found files from the D600 are hard to tell apart from D800 images downscaled to 24MP and examined at 100%.