Vivitar Series 1 13mm F/2.8 Ultra Wide Lens Manual Focus for Pentax DSLR's

The Vivitar 13mm F2.8 Ultra Wide Angle Lens is by far the sharpest, most flare resistant lens in its class. The lens is constructed of 14 elements in 12 groups, and features 2 ED lens element; one hybrid and one glass. These combine to minimize distortion and chromatic aberrations, and produce pictures that are razor sharp and clear, even at the corners!

The lens provides an ultra-wide angle field of view on both full frame and crop sensor cameras. Achieve wonderful perspectives and framings with a remarkable 115.7° angle of view on full-frame cameras, and 93.9° on crop sensors. The built in petal hood and multi-layered coating prevent both flare and ghosting in your photos.

Short focal lengths have a unique way of slightly distorting what you're photographing sometimes creating quite a dynamic effect. Another benefit of an ultra wide angle is the extensive depth of field. Especially in bright light, people and objects in the picture will be sharp from very close right out to infinity.