Panasonic GX850 has a Micro Four Thirds lens mount and currently there are 121 native lenses available for this mount.
The latest released lenses that are compatible with the GX850 are the Rokinon 7.5mm f3.5 Fisheye, the Samyang 7.5mm F3.5 Fisheye MFT and the OM System 90mm F3.5 Macro.
Panasonic GX850 doesn't have a sensor based image stabilization system but 34 of these lenses already comes with optical image stabilization.
Since Panasonic GX850 has a Four Thirds sensor, it has a focal length multiplier of 2�~ 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 GX850.
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Panasonic GX850 Lenses with Image Stabilization
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