I compared an old f/3.5 non Ai, a f/2.8 Ais and the latest AF f/2.8D. I just wanted to know which one is the sharpest at center and border to decide once and for all which one will remain in my bag.
I used a Nikon Df on a tripod, with Aperture Priority. This is far from a complete and scientific test.
First batch are pictures of a map in my wall, with the camera placed 1m away from it, so focus may not be perfect. 100% crops from the center and upper left side, lens wide open and two other apertures (f/5.6 and f/8).
Second batch are from my window, lens at infinity and 100% crops from center and border (close). Only at f/5.6.
They are all in this sequence (older at the top, newer at bottom).
1- NIKKOR 16mm f/3.5 non AI
2- NIKKOR 16mm f/2.8 Ais
3- AF NIKKOR 16mm f/2.8D
FOCUS AT INFINITY AND @ f/5.6