The Sony FE 400–800mm f/6.3–8 G OSS is a full-frame super-telephoto zoom lens designed for Sony E-mount cameras, built for extreme distance photography such as wildlife, birds, and sports. Key Overview This lens is the longest-reaching zoom lens in Sony's G series, covering a massive 400mm to 800mm focal range, allowing photographers to capture subjects that are very far away without needing to change lenses.