In addition to its 84 degree picture coverage and excellent speed, the 24mm F/2.8 offers exceptional resolving power and correction at all shooting distances. Its special formula embodies an independent rear lens group movement that dramatically improves image quality at close focusing distances. In fact, it is widely acknowledged to be the sharpest wide-angle lens for any slr 35. Compact size is another advantage of this lens design which achieves great light-gathering power without an extra-large front element.