The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 14-24mm F2.8 DG DN Art and the Pentax 12-24mm F4.0 ED AL for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is a crucial factor to consider when comparing two lenses. Sigma 14-24mm F2.8 DG DN Art is the longer of the two lenses at 131mm. The Pentax 12-24mm F4.0 ED AL with a length of 84mm, is 47mm shorter. On the other hand, the Pentax 12-24mm F4.0 ED AL has a larger diameter of 88mm compared to the Sigma 14-24mm F2.8 DG DN Art's 85mm diameter.
The weight of a lens is equally significant as its external dimensions, particularly if you intend to handhold your camera and lens combination for extended periods. Pentax 12-24mm F4.0 ED AL weighs 430g, 45% (365g) lighter than the Sigma 14-24mm F2.8 DG DN Art's weight of 795g.
Lens Mounts
The Sigma 14-24mm F2.8 DG DN Art has the Leica L lens mount whereas the Pentax 12-24mm F4.0 ED AL has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Leica SL3-P, Panasonic S1 II and Panasonic S1 IIE for the Leica L Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Sigma 14-24mm F2.8 DG DN Art is also available in the Sony E mount.
Focal Range
Sigma 14-24mm F2.8 DG DN Art has a focal range of 14-24mm and
1.7X zoom ratio .
On the other hand, the Pentax 12-24mm F4.0 ED AL has a focal range of 12-24mm and 2.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 18-36mm when used on a APS-C / DX format camera.