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 Carl Zeiss Distagon T2,8/25 for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is an important deciding factor when comparing two lenses. Carl Zeiss Distagon T2,8/25 is the longer of the two lenses at 90mm. The Sigma 24mm F1.8 EX DG with a length of 83mm, is 7mm shorter. On the other hand, the Sigma 24mm F1.8 EX DG has a larger diameter of 84mm compared to the Carl Zeiss Distagon T2,8/25's 64mm diameter.
The weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Carl Zeiss Distagon T2,8/25 weighs 480g, 4% (20g) lighter than the Sigma 24mm F1.8 EX DG's weight of 500g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Pentax KAF Mount for size comparison purposes.
Wideangle Prime Lenses in Pentax KAF Mount for Size Comparison
Lens Mounts
Both the Sigma 24mm F1.8 EX DG and the Carl Zeiss Distagon T2,8/25 has the same Pentax KAF lens mount. Some of the latest released cameras that are compatible with the Pentax KAF lenses are Pentax KF, Pentax K-3 III and Pentax K-1 II.
Sigma 24mm F1.8 EX DG is also available in Canon EF , Nikon F (FX), Four Thirds, Pentax KAF, Sony Alpha, Sigma SA, Canon EF, Sony Alpha, Sigma SA and Nikon F (FX) mounts.
Carl Zeiss Distagon T2,8/25 is also available in Nikon F (FX) mount.
Focal Range
Sigma 24mm F1.8 EX DG is a prime lens with fixed focal lenght of 28mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 42mm.
Carl Zeiss Distagon T2,8/25 is a prime lens with fixed focal lenght of 25mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 37.5mm.