Huge focal length, compact and lightweight design. The NIKKOR Z 800mm f/6.3 VR S, from Nikon, is a super-telephoto prime distinguished by the unique combination of one of the longest focal lengths available in a surprisingly portable package. This distinct design is made possible by the inclusion of a Phase Fresnel element, which cuts the overall weight by 50% and the length by 16% compared to the former F-mount 800mm f/5.6 lens.