Lens Lab
    Nikon Nikkor 18 mm f/ 3.5 Ai-S
    Nikon Nikkor 18 mm f/ 3.5 Ai-S

    Nikon Nikkor 18 mm f/ 3.5 Ai-S

    18mm · f/3.5

    Overview

    The Nikon Nikkor 18mm f/3.5 Ai-S is a compact manual-focus ultrawide lens praised for low distortion, with straight lines staying straighter than on 20mm Nikkors. However, it suffers from soft corners wide open and extreme vignetting on FX digital, improving only when stopped down to f/11 (Fred Miranda citing Bjørn Rørslett). Build quality is typical of the era, with a seven-blade diaphragm. It suits film shooters or those seeking a small, affordable ultrawide with controlled distortion, but is not recommended for general use on full-frame digital.