Pentax's budget full-frame telephoto zoom — the FA 80-320mm for K-mount with AF.
The Pentax SMC FA 80-320mm f/4.5-5.6 is a budget telephoto zoom for Pentax K mount with full-frame coverage. The FA designation confirms compatibility with both APS-C and full-frame Pentax bodies. Covering 80-320mm with autofocus, it provides affordable telephoto reach. The SMC coatings ensure reasonable contrast despite the budget positioning.
Optical performance is basic. Centre sharpness is acceptable at shorter focal lengths and weakens towards 320mm. The variable aperture limits low-light use. The 320mm reach provides useful telephoto coverage for casual wildlife and sports in good light. Autofocus uses the body's screw-drive motor. The SMC coatings help maintain contrast.
Pentax K mount, full-frame (FA). Filter thread is 58mm. Weight is approximately 465 grams — moderate. Build quality is basic plastic with functional construction. Benefits from Pentax's in-body Shake Reduction on digital bodies — a significant practical advantage given the lack of in-lens IS. Compatible with all Pentax K-mount bodies.
Very affordable on the used market. Check AF operation and smooth zoom. The 320mm reach with body SR support makes this more usable than non-stabilised competitors. A basic budget telephoto for Pentax shooters. The DA 55-300mm is the modern APS-C upgrade path.