Canon New FD 35mm f/2

Sharp in the middle at f/2, with corners that take their time. Shoot it wide open and the center holds detail cleanly while the edges trail behind, lagging the slower FD 35mm f/2.8 by roughly a stop out at infinity. They catch up by f/5.6 and the frame evens out by f/8. There is some veiling glow and a little softness at f/2, brightest in the center where it should be, and it cleans up fast by f/2.8. By the standards of a fast 35, the optics hold up well, and the rendering is the reason people keep this one.

The bokeh is the other reason. Backgrounds fall off quietly, no swirl, no harsh edges ringing the out-of-focus blobs, and the eight-blade diaphragm keeps highlights reasonably round through the middle stops. Stopped to f/4 or f/5.6 the whole frame snaps to a crisp, contrasty render. One thing the New FD has over its ancestors: the older breech-lock 35/2 versions used thoriated glass that yellows with age, and the New FD dropped that, so it does not warm your whites the way those do.

The New FD line, launched in 1979, was Canon's last manual-focus mount before the EF system arrived in 1987 and stranded every FD lens off the new bodies. That break is why these go cheap. A plain FD-to-EOS adapter can't reach infinity, because the FD register is shorter than EF, and the glass-corrected adapters that do focus to infinity sneak in an extra magnifying element that softens the image. Either way you lose the automatic diaphragm. So on a DSLR these were a compromise, and FD glass got passed over for years while Nikon and Pentax manual lenses kept their digital afterlife. Then short-flange mirrorless arrived. On a Sony, Fuji, or any short-register body, a dumb FD adapter brings this lens back at full quality, no glass in the path, and you get a compact fast 35 for cheap.

Flare is the honest weakness. The coatings are decent for 1979 but not modern, and shooting into a streetlight or a low sun throws veiling haze and the odd green ghost across the frame. A hood helps a lot. The 52mm filter thread is shared across most of Canon's FD primes, so one set of filters and one screw-in hood covers the whole kit, and that same thread takes an ND or a polarizer cleanly when you want to drag the shutter in daylight.

It draws people who shoot 35 as a walk-around documentary length: tight enough for environmental portraits, wide enough for a crowded sidewalk. The obvious rival in the FD world is the 35mm f/2.8, smaller and cheaper but a full stop slower, and then there's the collectible breech-lock thorium version that people chase for the radioactive front element and the price that comes with it. The New FD is the one you actually shoot. In dim interiors, meter it wide open at f/2 in Zone Light Meter so the reading matches the aperture you're really using, then watch your shadow placement, because that first stop is where contrast is lowest and the shadows want to go thin.