Nikon 500mm PF
Nikon 500mm f / 5.6E PF ED VR AF-S
Nikon couldn't have done it better. I never hoped that after buying the Nikon 200-500 I would need an update with the same focal length and same aperture. By specifications, an identical lens is ripped off by the zoom option and is a little lighter. But it's a hell of a difference. It is smaller and lighter, you can walk with it all day long. You can hold it close to your eye without being bothered by its weight. You keep it just above the water surface without worrying that you will get cramps and drown that piece of metal, plastic and a lot of glass in the irretrievable deep waters. That weight will give you a lot of freedom to take as a steep position as possible because you know that its weight will not take control over your body. However, 1 kg down for an additional $2000 would be a lot of money for me as well, so the glass has to defend the price in another way. And it can. An incredible sharpness that is comparable with what 70-200 offers and image stabilization, which with the combination of Nikon Z6 will let you take sharp pictures at 1/20 and even less, I believe. Unfortunately, even this lens is proof of how big the difference between professional and, let's say, amateur glass can be. Sharper, well balanced, and overall well designed for use.
What I think deserved more care is the lens hood. For me, the lens hood is a part of the lens, it should be and it needs to be taken into account when designing a lens. I always do use the lens hood. To prevent unwanted reflections, for protection of the front element (I do not use UV filters) and it's also great for protection against dirt. When you cross a meadow, field, etc., with the camera hanging over your shoulder, dust and pollen from the flowers don't reach your front glass just as well. I really liked the design on the old 300mm f4 D lens. The slide-out lens hood that was part of the lens is a great idea. Sturdy and compact, easy to push in-out. Sadly Nikon doesn't go in that direction when designing new lenses anymore.