On a Sony a7 the lens is apparently the lens. Unfortunately, I can stand in comparison with high quality Fujifilm and Canon lenses not quite confirm. The quite expensive Zeiss Prime instructs my a7 but quite tough Chromatic aberrations. The autofocus is however quite fast and processing excellent, although I would still like to see an aperture ring. What Zeiss but offered only in manual lenses. I use it to matching 49mm Zeiss polarizing filters (for I can not recommend - too expensive and even more chromatic aberration). What bothers me is the cheap-looking "SONY" camera cover. Since each "Alpha" looks chic lids from or why not Zeiss lid. But that's a matter of taste, and then the good piece is something prolliger.