The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Carl Zeiss Distagon T2/28 and the Venus 25mm F2.8 2.5-5X Ultra Macro 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. Carl Zeiss Distagon T2/28 is the longer of the two lenses at 93mm. The Venus 25mm F2.8 2.5-5X Ultra Macro with a length of 65mm, is 28mm shorter. On the other hand, the Venus 25mm F2.8 2.5-5X Ultra Macro has a larger diameter of 82mm compared to the Carl Zeiss Distagon T2/28's 64mm 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. Venus 25mm F2.8 2.5-5X Ultra Macro weighs 400g, 23% (120g) lighter than the Carl Zeiss Distagon T2/28's weight of 520g.
Lens Mounts
The Carl Zeiss Distagon T2/28 has the Pentax KAF lens mount whereas the Venus 25mm F2.8 2.5-5X Ultra Macro has the Pentax KAF2 lens mount. Some of the latest released cameras that are compatible with these mounts are Pentax K-3 III Monochrome, Pentax KF and Pentax K-3 III for the Pentax KAF Mount and Pentax K-3 III Monochrome, Pentax KF and Pentax K-3 III for the Pentax KAF2 Mount.
Carl Zeiss Distagon T2/28 is also available in Canon EF and Nikon F (FX) mounts.
Venus 25mm F2.8 2.5-5X Ultra Macro is also available in Canon EF , Nikon F (DX) and Sony E mounts.
Focal Range
Carl Zeiss Distagon T2/28 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.
On the other hand, the Venus 25mm F2.8 2.5-5X Ultra Macro 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.