This is essentially a request for purchase advice. My problem is that I like city streets at night, and when I take pictures thereof with a Nikkor 50 mm 1:1.4D on a Sony NEX-7, it looks horrible: for seemingly every light source, there's a blue blob elsewhere in the picture.
I'd be willing to throw money at the problem, if that would help. Would it? I was looking at M-mount lenses via adapter (e.g. Voigtländer, Zeiss) but of course I might be jumping out of the frying pan into the fire.
Has anyone had any experience with this, that is: Advice which lenses might work well in these circumstances?