This particular lens has auto focus for best possible result. The filter size is 52 mm, good to know if you like to use filters.
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TT Artisan 50 mm F1.2 APS-C Lens Connection Leica L Sigma Panasonic Black Manual Focus Optical Construction 11 Elements in 7 Groups
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TTArtisan 50mm f1.2 Lens for Leica L-Mount - Black
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TT Artisan 50 mm F1.2 APS-C Lens Connection Leica L Sigma Panasonic Black Manual Focus Optical Construction 11 Elements in 7...