I already have a 35/2 AF-D, and I'm thinking of eventually upgrading it to a 35/1.4 AIS, which is one of the few lenses that I've never used. Is the 35/1.4 better than the 35/2 at f/2? I care about sharpness, contrast, and bokeh smoothness. I don't care about autofocus, since this lens will be for my manual focus cameras. I already have a Sigma 30/1.4 for my D50. Unfortunately, that lens gives me black corners on FX.