If you look at the optical construction, it's very very similar to the AF-D 50/1.4 except for the rear group which has one more element.
Sigma's 50/1.4 is quite similar also except for the larger front element and the rear group which incorporates a piece of aspherical glass. Based on MTF alone, I would go for the Sigma if the price were similar, but the thought that it may have front/back focus issues, I would think again. ;p


Last edited: