The Nikon D610 is essentially a revamp of the older D600 camera with a few small enhancements. It is a very small and light weight camera offering 24.3 megapixels on a CMOS sensor.
In differing from the D600 it has improved white balance and 39-point autofocus and it has a capability to shoot at up to 6 frames per second with a completely new shutter mechanism. The new shutter has also quiet shooting options. In all other aspects it is a D600.
If you want a full frame camera at an entry level price then this may be the camera for you.
It has a magnesium alloy construction and excellent weather resistance which offers excellent sturdiness for outdoor use.
The ISO sensitivity range is from ISO100 to 6400 and expandable from ISO50 to ISO25,600.