Optical Design: 4 groups of 4 pieces of optical structure, multi layer MC coating can suppress lens spot and ghost, improve contrast and color authenticity. Compatibility: When used with the included T2 FX adapter , it can be used with a half frame micro single camera X lens. 500mm F6.3 Achromatic Refraction Telephoto Lens: The 500mm F6.3 ultra long zoom lens is a nice choice for bird and wildlife photography as well as ultra long distance shooting. Lens Type: A accuracy achromatic refractor design for nice peak contrast and flare control images. You can use this lens in M manual exposure mode. Physical Design: Also includes a tripod mount and detachable lens hood to help minimize lens ghouls. A rotating tripod mount provides optimal balance and allows quick and easy vertical format shooting when rotated.