Pentax ist DS2 has a Pentax KAF lens mount and currently there are 163 native lenses available for this mount.
The latest released lenses that are compatible with the ist DS2 are the Pentax FA 50mm F1.4 Classic, the Pentax FA 50mm F1.4 and the Pentax 16-50mm F2.8 ED PLM AW.
Pentax ist DS2 doesn't have a sensor based image stabilization system but
13 of these lenses already comes with optical image stabilization.
Since Pentax ist DS2 has a APS-C sensor, it has a focal length multiplier of 1.5× so you have to multiply lenses original focal length with this multiplier to find the Full Frame equivalent focal length of the lens when mounted on ist DS2.
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