I use this on a Sony A5100 camera. This lens seems to weigh more than the camera. The frame is mostly metal parts and obviously contains a lot of glass elements, hence the weight. Manual focusing isn't the easiest of tasks on the A5100, but it works for still subjects if you have the patience. IMAGE QUALITY We buy lenses for the image quality and they don't disappoint. This allows you to capture good sharp images with good bokeh at F2. Color reproduction is good and wide-angle distortion is well controlled. FEEL It feels massive and feels like it needs rough handling. This is a dual ring fully manual lens. One for focus and one for aperture. The aperture ring is fine, as I expected. I have a fundamental problem with the focus ring. The ring requires too many turns to focus from near objects to far objects and vice versa. If I had to fine-tune the focus, it would be easy, but if the focus difference is too big, it takes too much effort to turn the ring. The ring feels too stiff compared to other Sony and Nikon OEM lenses I've used. That seems to be the Achilles' heel of this lens.