Astro photography cameras ?
Dan Finnerty wrote:
...I am not familiar with Nikons, but I've heard it said that Nikon does some noise pre-processing of raw files, which is undesirable for astro work.
I'm not 100% sure, but I don't believe this is still the case with the D800/D4, although it certainly was with previous cameras.
For lenses, an important characteristic is low coma. Some lenses are very well controlled for coma meaning that when shot "wide open" the small point lights do not get 'smeared'. The new Nikon 35G is a good example, as is the older but still very good 180mm f/2.8.