A brilliant lens. It was a very advanced when it was introduced, having a modern optical design, only the second lens with multi-layer coating (after Nikkor-N 35/1.4), and the third lens with CRC (after 24/2.8 and 35/1.4).
A small correction:
"One appealing feature of this lens is how close it’s able to focus. The later Ai and Ai-S versions focus even closer which makes them even more useful."
The original pre-AI and AI versions all focus to 0.3m which was already very close for a 28mm lens - that is half the distance of the Nikkor-H 28/3.5 from the same period. That is very impressive when you consider it is 1 1/2 stops faster. In the AI-S version the focus range was extended even further to 0.25m. I'm not sure if the optics were refined at that point or if they just extended the existing CRC mechanism. Note the AI-S 28/2.8 focuses even closer to 0.2m.
"Vignetting is pronounced wide-open which improves considerably by f/2, it is nearly-gone from f/2.8"
I assume that should read: "improves considerably by f/2.8, it is nearly-gone from f/4"?
