Two extra-low dispersion (ED) glass lenses are used for correcting the chromatic aberration. This telephoto lens provides high quality delineation performance without compromises. When combined with the 645D, you can experience breathtaking resolutions with stunning clarity.

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When combined with the rear converter in bird or other wildlife photography, this lens can also be used as a 420mm F5.6 or 600mm F8 super telephoto lens. AF/MF switching can be performed quickly by simply moving a wide focus ring forward or backward. The lens includes a rotating tripod seat with clip to enable speedy switching between vertical and horizontal orientations.