Check out the Mansurovs for an excellent comparison chart between the Nikon D600 and D800. I’ll just highlight one bit from that chart:
|Sensor Pixel Size||5.9µ||4.8µ|
So the individual pixels on the D600 are significantly larger than the D800. This could translate to outstanding high ISO performance.
On the other hand, the Strobist has looked at the specs and decided that this camera is not for him. His reason? Limitations on flash sync.
When you are balancing flash in bright ambient, you start at your max sync for your shutter speed. That will give you the most flash-friendly corresponding aperture, whether you are normally exposing or underexposing the ambient.
Think about it: 1/250th at f/16 equals 1/500th at f/11. Since the flash only cares about the aperture, you could balance in the same light with half of the flash power.
True, it is only a third of a stop as compared to 1/250th. But with speedlights and daylight, that is a critical third of a stop. To be clear,this camera makes every single flash you own less effective.
Also, the difference between 1/250th and 1/200th sync is deadly when it comes to stopping action when balancing flash and ambient. 1/250th is dicey enough. 1/200th just doesn’t work.
This doesn’t impact my style of shooting but perhaps it would impact yours?