A:Answer The Nikon AF-S DX NIKKOR 18-300mm f/3.5-5.6G ED VR Standard Zoom is an amazing lens that provides ultra-fast, ultra quiet autofocusing and has a vast array of elements and groupings for remarkable image capture. This DX-format lens will provide excellent quality when attached to the Nikon D850 DSLR FX-format camera, however, you will experience a 1.5 image crop. For a lens choice that will allow you to the get quality images without a 1.5 DX crop try looking into FX lenses like the Nikon AF-S NIKKOR 28-300mm f/3.5 -5.6G ED VR Standard Zoom or the Nikon AF-S NIKKOR 24-70mm f/2.8G ED. To learn more about DX crop please contact Nikon Support.