Sigma 8-16 mm F/4.5-5.6 DC HSM Lens For Pentax K. For APS-C crop-sensor cameras. Compatible with all Pentax DSLRs. For the Pentax K-1 full-frame DSLR, it fills the frame only at 16mm. At other focal lengths the K-1 should be set to crop mode. This is an ultra wide angle zoom lens. At 8mm the […]