The Nikon AI-S Nikkor 600mm F/4 ED-IF manual focus telephoto prime lens was manufactured between 1982 and 1986. The lens is 1.64 feet long and weighs 27.5 pounds not including 2x Nikon TC-300 teleconverter, which was used to achieve the 1200mm focal distance used to render this image.
No vibration reduction was available on older Nikon lenses. The increased image magnification of the 2x TC-300 teleconverter coupled with the 600mm lens amplifies the slightest camera movement and causes image blurring.
A Gitzo GT5533L Systematic Series 5 Carbon Fiber Tripod (Long) was used in combination with a WH-200 Wimberley gimbal head to hold the lens steady enough to eliminate camera shake. The WH-200 Wimberley gimbal head which has a 100 lbs load capacity weighs 3.15 lbs. My Nikon D850 camera weighs 2.2 lbs. Therefore the total tripod load is around 32.22 lbs.
A handy rule of thump is, tripod load should minimally equal two times the actual load or, 64.44 lbs in this case. The tripod’s load capacity of 88 lbs exceeds the rule of thumb by 23.56 pounds, and indeed the Gitzo tripod in conjunction with the Wimberley gimbal head held the 27.5 lbs lens steady. A 1/2000 sec shutter speed and a Nikon MC-30a remote trigger release were employed to further minimize camera shake. In addition to doubling the focal length the TC-300 teleconverter stops down this f/4 lens to f/8. At f/8 the auto iso used to render this image with a 1/2000 sec shutter speed was 1600.
Finally, the Nikon D850’s focus peeking was used to obtain focus in live view. Although focus peeking is common in the electronic view finders of mirrorless cameras, to the best of my knowledge the D850 is the only full frame digital single lens reflex (DSLR) camera to offer focus peeking.