Canon FD 100mm f/2

Almost nobody needed an f/2 hundred. Canon already sold a perfectly good FD 100mm f/2.8 that was smaller, cheaper, and sharp enough for any magazine, so the f/2 had exactly one reason to exist: a stop more light and the shallower, rounder rendering that comes with it. People who shoot it shoot it for that stop and that look, not for the spec sheet.

Wide open the plane of focus sits in a thin band and the background falls away into soft, evenly lit out-of-focus blur with round highlight disks that hold their shape toward the center. A head-and-shoulders frame separates cleanly from the backdrop without any harsh edge ringing. There is a little spherical glow at f/2 that takes the bite off skin and fine detail, and it tightens up quickly. By f/2.8 contrast snaps in, and from f/4 to f/8 this is a genuinely crisp lens, sharp across most of the frame with the slightly warm, neutral color the FD primes tend to give you. The aperture closes to f/32 if you want everything, but nobody buys a 100mm f/2 to shoot it at f/32.

The optics are a Gauss-derived layout, six elements in four groups, the same Planar lineage that runs through most of the fast short teles of the era. This is a New FD lens, the FDn generation Canon introduced at the turn of the eighties with the satin-black plastic-skinned barrel and the push-button bayonet release that replaced the older breech-lock collar. It is a dense, solid piece of glass for its focal length, with a long smooth focus throw that suits deliberate work and rewards manual focus on a bright screen. The front element is set behind a 52mm thread, which is small for a fast 100 and keeps the whole package more compact than you would guess from the weight.

It earns its keep on portraits and short-documentary work. On a film SLR you get working distance without crowding the subject, flattering compression, and enough speed to keep shooting as a room goes dim. At f/2 you can hand-meter an interior in failing window light and still hold a usable shutter. Meter wide open at f/2 with Zone Light Meter so the reading reflects the light actually reaching the film, then stop down to taste for the depth you want.

Flare is where it shows its age. The early-eighties FD coatings are not modern multicoating, and a strong source just outside the frame will throw veiling haze and lift your blacks toward gray. Use the hood, and against backlight plan to lose contrast you would keep with a later lens. The practical catch is the mount: this is FD, so on mirrorless you adapt it manual-only, and there is no clean adapter onto a Canon EF body without corrective optics that ruin the point of owning fast glass.

Today it sits in the affordable-cult tier. It costs more than the plentiful f/2.8 hundred and gets cross-shopped against the Minolta MC 100mm f/2.5 and the various fast 105s and 135s of the period, but the f/2 keeps demand steady among people who want that one extra stop on film. The 52mm thread is common, so screw-on diffusion or a light ND for shooting wide open in daylight is cheap and easy to find.