Right, I'm a Fine Art student, and one of my main modules is photography. I currently use a Nikon D3100 with the 18-55mm kit lens, but have a 55-200mm VR and a 35mm 1.8 prime (my preferred lens). My favourite and most used style of photography is low-light/night photography, however that's not really a strength of the D3100, as I've found I often have noise, slight colour altercations and sometimes some banding, which is annoying as it affects my photos.. I shoot only in RAW, using either M or A settings.
I don't have a flash, but I will consider buying one, but what I'd like to know is whether it would give any benefits? Or whether there are any lenses that would suit my purposes any better? The other option I'm considering is between a D90, D5x00 and the D7000, but I'm not sure about weather the ISO is considerably better.. I can't afford a d7100 or to go FX. Can anyone help me in any way? Thanks in advance,