Nikon really threw their optical weight around with the 28mm f/2.8 Ais, front CRC, Nikon Intergrated Coatings, and what looks to me as an extended optical design time, probably using a fairly cutting edge computation programs/hardware (for the time), all based on an already great Nikkor optic, the 28mm f/2. My 2.8 Ais version compares favorably to my 28mm f2, and both were better at wider stops closer in than my version of 28mm f/2.8 Ai, which was an actually quite good lens in most scenic shots, just not closer up nor wider open. I sold off the 2.8 Ai and kept the f/2 and the 2.8 Ais.