Pentax's updated AF film SLR — K-mount, 30s-1/4000 shutter, built-in TTL flash, sold as SF1n in the US
The Pentax SFXn is an autofocus 35mm SLR introduced in 1989 as the refined successor to the SFX, the camera that had launched Pentax's autofocus SLR line two years earlier. In North America it was sold as the SF1n, while SFXn was the designation used in the UK and other markets. It sat at the top of the SF series until the Z/PZ line replaced it.
It uses the KAF bayonet and accepts Pentax K-mount lenses, with autofocus via the body-driven system in single or continuous modes and electronic focus confirmation for manual lenses. The electronically controlled vertical metal focal-plane shutter runs from 30 seconds to 1/4000 — up from 1/2000 on the SFX — and the drive rate rises to 2.2fps. Exposure modes span program, shutter-priority, aperture-priority and metered manual, and the built-in retractable flash offers TTL metering with automatic fill capability.
Like other SF bodies it is a large, chunky camera by modern standards, but the full mode set, TTL flash and broad K-mount compatibility make it a cheap way into autofocus film photography, and it doubles as a capable manual-focus body. Early screw-drive AF is audible and modest by later standards.
These bodies are battery-dependent and use a lithium cell, so confirm the camera powers on, the LCD panel is intact without bleed, and the shutter fires at both speed extremes. Check the pop-up flash rises and charges, that the film door closes with sound seals, and that autofocus drives smoothly with a lens fitted. Values are low, so favour clean, fully working examples over projects.