The ZEISS Loxia 21 is a superbly sharp lens that renders beautiful images. It's perfect for landscapes and astrophotography. The lens is manual focus-only but that's fine with me as I always shoot landscapes and astro with manual focus. The bonus is that the lens is very light and compact. When I travel with it I just bring along screw-in ND filters and a circular polarizer and the whole kit is so much lighter than bringing my 16-35 with all the square filters.