The 28mm f/3.5
has a long history reaching back to 1960, with the Auto-H, and cumulating in the Nikkor 28mm f/3.5 AI/AIS of the late 70s/early 80s. All variations had a 6/6 design although the Auto-H and the AI/AI-S having different optical formula. By the time the AI/AI-S was released in 1977/1981, it was already seen as the economical 28mm with its slower f/3.5 max aperture with the f/2 K and f/2.8 K/AI making its debuts in 1975 and 1974 respectively.
The f/3.5 AI-S was sunset in 1983 by which time the
very well regarded 28mm f/2.8 AI-S had been released. Over time, the 28mm f/2.8 AI-S reputation (and its long production run) keeps it in conversations but if you were to consider a manual 28mm, is the slower f/3.5 worth considering?