This particular lens has a 0.3-metre minimum focusing distance and a 30 mm maximum focal length. The filter size for this lens is 52 mm, so make sure the filters will fit.
From London Camera Exchange
Sigma 30mm F1.4 DC DN Contemporary - For Micro Four Thirds
TechintheBasket
Sigma 30mm f/1.4 DC DN Contemporary Lens for Micro Four Thirds
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