Pentax SMC Pentax-FA* 85mm f/1.4 IF (K)

Wide open at f/1.4, a face shot with this lens carries a soft glow across the skin while the plane of focus lands thin over the eyes, and everything behind it falls away into rounded, edge-free discs. The out-of-focus discs stay smooth, free of the harsh onion-ring texture that shows up on plenty of fast 85s. Stop down to f/2.8 and the glow hardens into clinical sharpness while the background stays creamy. That combination, soft wide open and crisp two stops down, is exactly what a head-and-shoulders portrait wants.

The SMC in the name is Pentax's Super Multi Coating, and it does real work here. Color comes back warm and saturated, and the lens holds contrast shooting straight into a window or a low sun where lesser glass would veil over. It is an internally focusing design (the IF), so the front element never rotates and the barrel never changes length, which matters if you run a polarizer or a grad on the 67mm thread. This is FA* glass, the top tier of Pentax's autofocus film line, built for the early-90s bodies and still mounting on every K-body the company has made since.

Eighty-five millimeters on 35mm is the head-and-shoulders length, and the lens is built around that frame. Portrait shooters who stayed with Pentax made it the center of the bag. Put it on an APS-C Pentax DSLR and it frames closer to a 130, tighter, better for a filled headshot than for context. Either way the draw is the subject separation, the way a person lifts cleanly off a smoothed-out background.

The honest weakness is autofocus. It is screw-drive, body-driven, so it crawls and clatters in the dim rooms where you most want an f/1.4 lens. Depth of field wide open is so shallow that catching the near eye is genuinely hard. There is longitudinal CA at f/1.4 as well, green and magenta fringing on bright edges, though it tidies up by f/2.8. And it is a heavy lump of glass on the front of a film body.

Pentax dropped it in 2004 and then went years with no f/1.4 replacement, so clean copies hold their price and people still hunt them. It gets cross-shopped against the Canon and Nikon 85/1.4s by shooters choosing which system to live in; inside the K mount it has no real rival from the era. The aperture ring means it meters cleanly on a manual film body. One practical note: opening up in a dark interior, meter the shadow you care about in Zone Light Meter and place it on the zone you want, because f/1.4 buys you the shutter speed to shoot there but the focus plane is unforgiving, and you want exposure settled before you fight for the eye.