Image courtesy Camerasize
As you can see the Samyang nearly has the same Sony GM size but it is a lot lighter. The Sigma is considerably bigger and heavier. You can also view the exact and accurate specs comparison on this BH page .
Samyang 135mm f/1.8 FE preorder at BHphoto , Adorama . Calumet DE , FotoKochDE and at WexUK .
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