The .3x Ultra Fisheye Adapter offers an extreme fisheye effect and a high degree of barrel distortion. It exaggerates depth by pulling nearby objects closer and causing distant objects to recede into the background. The 35mm focal length equivalent is 13mm. With the Century Fisheye, capturing extreme action shots is dramatic and practical. With its almost total depth of field and unmistakable style, this adapter is a must for action sports shooters. For use with the Sony bayonet mount.