I recently acquired a Sony a7 II after owning several NEX cameras over the years. During my research to plan for future lens purchases, I came across an unexpected review of the Sony Zeiss 55mm F1.8 Sonnar T* FE ZA by the Lonely Speck.
While a 55mm lens might not be a standard focal length for traditional astrophotography, Ian Norman has created some beautiful high megapixel images with this lens on his Sony a7S II. Astrophotography performance is a unique way to judge optical performance because of how demanding it can be, but the Sony Zeiss 55mm handles the task with ease. You can read more about how the lens performed on Lonely Speck.