The overall performance for the D610, in real world experience, is identical to that of the D600. Besides the lack of major dust and oil on the sensor, the two cameras perform in the exact same way.
I have owned a D600 for a nearly a year, and the D610 feels identical to me in terms of its performance and usability. There is a slight difference in FPS shooting speed (6FPS for this camera vs. 5.5 FPS for the D600), but it is not noticeable in everyday shooting. The camera performs very well and shoots quickly. The 39 point AF system is identical to the D600; however, my opinion of the AF coverage area bears repeating: it is smaller than I would prefer. It is easy to adapt to, however, by either focusing on one of the available points, using the DX crop mode, or using focus and recompose techniques. As in the D600, the sync speed is 1/200th of a second.
Nikon states that the D610 features improved white balance, and the colors are good our of camera in the video and still photograph modes alike. Image quality is great, and the camera’s dynamic range is fantastic. The D600 handles high ISO very well, noise is not as issue until about ISO 3200 or higher, and I find images useable at 6400 and sometimes even higher than that.
If you choose to purchase the D610 as a kit, the 24-85 f/3.5-4.5G VR kit lens will be a great starter lens. The variable aperture zoom is probably not going to satisfy the pros, but a budding amateur will most likely enjoy the lens. This kit lens is nicer than most and has a flexible shooting range. The lens is adequately sharp, but is not the sharpest lens you will find.
Surprisingly, the inexpensive 85mm f/1.8 (street price of $500) is a fantastic lens for this camera. It produces extremely sharp results. For the money, it’s hard to beat the value of this lens. The Sigma 35mm f/1.4 is also a stellar lens for this camera. It produces consistently sharp results.
Video and Image Quality
The D600’s image quality is fantastic and the camera’s dynamic range is impressive. The camera produces images with very little noise up to an impressively high ISOs. The image below was taken at ISO3200.
Below is a time lapse video taken with the Nikon D610. The video was taken over a two hour time period. A series of 7200 images were captured during this time. The video shows small amounts of dust that attached to the sensor. The Nikon 85mm f1.8 lens was attached to the camera for the video. Overall, the video shows that the dust issue is on-par with other DSLR cameras. The main concern is that dust appeared on the sensor while the lens was attached. This means one of two things (or both): either the camera had some dust already inside of it when this time lapse was started or the camera has an issue with dust entering the camera even when a lens is attached. The second scenario is much more troublesome and will fall in line with dust issues with the D600. However, we didn’t see a large amount of dust on the sensor even after a month of repeated use. This would suggest that the dust in the time lapse video was already present in the camera.
Here is a still image taken after the time lapse. The dust spots have been circled. The image shows 8 spots (one was hard to tell and one looked more like a smudge than a spot). Admittedly, this is totally nitpicking the image and the camera. The image was shot at f/16 on a white piece of paper and magnified 200%-300% in order to expose the flaws. In real world use, the dust spots would generally not be visual at wide open apertures. Also, when other elements are thrown into the image (people, animals, backgrounds, etc) the spots would make them even harder to see. That being said, no one wants excessive dust on their camera’s sensor. And when paying $2000 for a camera, buyers want to know their investment isn’t going to have fatal flaws.