The type of photography that you are planning to use is an important decision factor. Here we have evaluated the ZEISS Loxia 21mm F2.8 and the Voigtlander 20mm F3.5 SL II 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. ZEISS Loxia 21mm F2.8 is the longer of the two lenses at 72mm. The Voigtlander 20mm F3.5 SL II with a length of 29mm, is 43mm shorter. On the other hand, the Voigtlander 20mm F3.5 SL II has a larger diameter of 63mm compared to the ZEISS Loxia 21mm F2.8's 62mm 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. Voigtlander 20mm F3.5 SL II weighs 205g, 47% (189g) lighter than the ZEISS Loxia 21mm F2.8's weight of 394g.
Filter Threads
Both the ZEISS Loxia 21mm F2.8 and the Voigtlander 20mm F3.5 SL II have the same Filter thread size of 52mm.
Below are links to the 52mm filters that we recommend you to consider for these lenses:
Lens Mounts
The ZEISS Loxia 21mm F2.8 has the Sony E lens mount whereas the Voigtlander 20mm F3.5 SL II has the Nikon F (FX) lens mount. Some of the latest released cameras that are compatible with these mounts are Sony FX5, Sony A7R VI and Sony A7 V for the Sony E Mount and Nikon D6, Nikon D780 and Nikon D3500 for the Nikon F (FX) Mount.
Voigtlander 20mm F3.5 SL II is also available in Canon EF and Pentax KAF mounts.
Focal Range
ZEISS Loxia 21mm F2.8 is a prime lens with fixed focal lenght of 21mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
31.5mm.
On the other hand, the Voigtlander 20mm F3.5 SL II is a prime lens with fixed focal lenght of 20mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 30mm.
