*Some* of the DX lenses will cover full-frame even though they aren't designed to do so (the 18-55mm is one, I had one once and it would cover a 35mm frame from 24mm to 55mm). However, I'm not aware of any DX lenses that aren't also G-series, therefore they will not allow aperture adjustment on cameras like the FM. A better modern super-wide lens for the FM would be the AF-Nikkor 18-35mm f/3.5-4.5D, which is a full-frame lens with an aperture ring.