Neither are any better than the other really Greg. I don't agree with what H said about skin tones. Being a Canon fan boy has tainted his unbiased point of view.
. Alex is right about the 14-24. That image I posted recently of the milkway over Clayton obs was taken with that lens. Using pretty high ISO and 50 second single sub gives you an idea what the Nikon gear is all about now. For astro work I reckon both the high end backs are worth looking at now. For years Canon had the edge but that is pretty well over now. So you have a greater choice now. Mind you I have been a Nikon user since the early 80's so I have a slight bias myself.
