If you're looking for a wide-angle lens for your Sony E-mount camera, this is a great option. After a few test shots, the best place for this lens is definitely f/8, where the image is sharpest. Using this lens fully closed at f/22 is not recommended as it is noticeably soft but not unbearable. It produces a decent sun star effect for point lights when shot fully closed. This lens can be used wide open at f/2, which is probably what attracts most people to this lens. For those of you looking for a great lens for astrophotography, this is the best choice for the E-mount due to its large aperture and relatively low distortion. Shooting wide open does soften the images a bit around the edges, as well as a bit of chromatic aberration, but nothing that can't be corrected with post-processing software like Affinity Photo for Mac users. Overall, I am very satisfied with using this lens for landscape and astrophotography. This is a great wide-angle lens for E-mount cameras. UPDATE: PHOTOS ADDED Miami Skyline - taken at f/22 Jamaica Falls - taken at f/8 Milky Way and ISS - taken at f/2