Samsung GX-1S 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 GX-1S are the Pentax FA 50mm F1.4 Classic, the Pentax FA 50mm F1.4 and the Pentax 16-50mm F2.8 ED PLM AW.
Samsung GX-1S doesn't have a sensor based image stabilization system but
13 of these lenses already comes with optical image stabilization.
Since Samsung GX-1S 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 GX-1S.
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Samsung GX-1S Lenses with Image Stabilization
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