Nikon Nikkor 55mm f/1.2 AI

Wide open at f/1.2 this lens glows, and that glow is most of why anyone bothers with it. A soft veil of spherical aberration sits across the frame, focus snaps to a thin sliver, and out-of-focus highlights bloom into soft discs. Some people chase that look for years. Others mount it once, see the haze, and move on. Shoot a backlit portrait at f/1.2 and you get a low-contrast, slightly hazy rendering that a modern lens simply will not hand you out of the box.

It is a double-Gauss design, a fast normal opened up about as far as the mid sixties could manage without the glass falling apart. Pulling a 55mm to f/1.2 in that era meant accepting aberrations that a slower 50mm f/1.4 never carries. The trade is real. By f/2.8 the haze burns off and you are looking at a genuinely sharp, contrasty lens with neutral color, though you will still catch some longitudinal fringing, green-magenta, on out-of-focus highlights wide open. By f/5.6 the center is excellent. The corners keep trailing it, with a little residual softness and edge CA that you can stop down further or just live with.

The AI version is the 1977 to 1978 update, the one with the metering ridge that couples to aperture-indexing bodies. Same Nikon F mount that has carried forward for decades, which is half the reason these still see use. Mount it on a modern Nikon and meter through it, or adapt it to a mirrorless body and focus by eye. The 52mm filter thread is the standard Nikkor size, so your existing rings and ND filters thread straight on without hunting for an oddball diameter.

Who reaches for one: available-light shooters, documentary and concert photographers working in dark rooms, portrait people after that vintage falloff. It is not a landscape lens. Nobody buys an f/1.2 to shoot a ridgeline at f/11, and stopped down to f/16 you gain nothing a cheaper f/1.4 would not give you. The honest weakness is f/1.2 itself. Critical sharpness lives a stop or two down, so if you need bite at full bore, look elsewhere.

Today it sits in the affordable-classic bracket. People cross-shop it against the later, sharper 50mm f/1.2 AI-S, against fast Canon FD and Olympus glass, and against the modern f/1.4 autofocus normals that out-resolve it on every chart and leave the rendering on the floor. The reason this one still sells is how it draws, not what it scores.

One practical note for film. Metering wide open in dim light is exactly where f/1.2 earns its keep, but know what the haze does and does not change. Veiling flare at f/1.2 lowers contrast and lifts the look of your shadows; it does not change the actual exposure, since the meter is reading scene luminance and the f-stop, both of which are correct. Take the Zone Light Meter reading and trust it. Just expect the tonal scale to compress a touch wide open, so meter normally and resist the urge to over-correct for a flatness that is coming from the glass, not the exposure.