I've had it for 4 weeks and take pictures with my A7R only with the part. The pictures are amazing HOT TOPIC Example: Handsfree at 1/20 sec and ISO 400 at 200mm f4 and the images are still sharp !!! In combination with the Sony A7R a peak optical power was measured at the DxOMark Labs. It currently owns the place 84 within more than 7600 examined lens camera systems.