Hello! I'm new in photography, it's been only 5 months I shoot photos. last summer, I bought Nikon D60 with 18-55mm lens. but when it comes to low light photography I'm not very satisfied. some time ago, a friend of mine told me to buy 50mm F/1.4G autofocus lens for my camera, and it would help.. Now I'm wondering, If I buy that lens for 450$, would the quality improve (I mean the noise and dirt) or it will just make a good depth of field (bokeh) and that's all? I'm sure I sound very dummy right now, but please explain whether the quality depends on Lens or the Camera itself? and what advantages will I have with 50mm Lens?