The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 24mm F1.8 EX DG and the Pentax 14mm F2.8 ED 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 24mm F1.8 EX DG is the longer of the two lenses at 83mm. The Pentax 14mm F2.8 ED with a length of 69mm, is 14mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 84mm.
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 14mm F2.8 ED weighs 420g, 13% (65g) lighter than the Sigma 24mm F1.8 EX DG's weight of 485g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Pentax KAF Mount for size comparison purposes.
Wideangle Lenses in Pentax KAF Mount for Size Comparison
Filter Threads
Both the Sigma 24mm F1.8 EX DG and the Pentax 14mm F2.8 ED have the same Filter thread size of 77mm.
Below are links to the 77mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Sigma 24mm F1.8 EX DG and the Pentax 14mm F2.8 ED has the same Pentax KAF lens mount. Some of the latest released cameras that are compatible with the Pentax KAF lenses are Pentax K-3 III Mono, Pentax KF and Pentax K-3 III.
Sigma 24mm F1.8 EX DG is also available in the Canon EF , Nikon F (FX), Four Thirds, Sony Alpha, Sigma SA, Canon EF, Pentax KAF, Sony Alpha, Sigma SA and Nikon F (FX) mounts.
Focal Range
Sigma 24mm F1.8 EX DG is a prime lens with fixed focal lenght of 24mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
36mm.
On the other hand, the Pentax 14mm F2.8 ED is a prime lens with fixed focal lenght of 14mm which has an effective (full-frame 35mm equivalent) focal range of 21mm when used on a APS-C / DX format camera.