The DV Series .55x Reversible Wide Angle Adapter is the first dual purpose DV lens accessory. When attached to the lens front in one direction, the .55x performs like Century's other high-quality wide angle adapters - offering a significantly wider angle of view with minimal distortion. On the JVC GY-DV300U, the .55X provides a horizontal viewing angle of 75°.When you want to go even wider with a fisheye effect, simply remove the .55X optical element, flip it around, and thread it on the other way. It becomes a fisheye adapter. Oriented this way, the .55X provides a wider angle of view with pronounced barrel distortion. When used as a fisheye adapter on the JVC GY-DV300U, the .55X offers a horizontal viewing angle of 94° and a diagonal angle of 117°.