Although it has 62mm filter thread, it's a small and light weight (260g) lens. Focusing takes only 1/4 of a turn and the lens tube extends only about 0.4cm. On a full frame camera and focus at infinity, light fall off at the corner is visible below f11 (with standard B+W 010 filter), but not so serious after f5.6- removing the filter helps, but I have yet to test that in detail. Extreme corner softness is almost 100% gone at f8 (only a trace of it at the corner when viewed at 100%), and in my opinion corner softness is not a problem from f5.6. I would rate its overall sharpness better than the 18-35mm.