The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon 24mm F2.8 STM 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. Voigtlander 20mm F3.5 SL II is the longer of the two lenses at 29mm. The Canon 24mm F2.8 STM with a length of 23mm, is 6mm shorter. On the other hand, the Canon 24mm F2.8 STM has a larger diameter of 68mm compared to the Voigtlander 20mm F3.5 SL II's 63mm 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. Canon 24mm F2.8 STM weighs 125g, which means it is 80g (39%) lighter than the Voigtlander 20mm F3.5 SL II which has a weight of 205g.
Filter Threads
Both the Canon 24mm F2.8 STM 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 Canon 24mm F2.8 STM has the Canon EF-S lens mount whereas the Voigtlander 20mm F3.5 SL II has the Canon EF lens mount. Some of the latest released cameras that are compatible with these mounts are Canon T8i, Canon 90D and Canon SL3 for the Canon EF-S Mount and Canon 1D X III, Canon 6D MII and Canon 5D MIV for the Canon EF Mount.
Voigtlander 20mm F3.5 SL II is also available in Nikon F (FX) and Pentax KAF mounts.
Focal Range
Canon 24mm F2.8 STM is a prime lens with fixed focal lenght of 24mm which has an effective (full-frame 35mm equivalent) focal range of
38.4mm when used on a APS-C / DX format camera.
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 1.6x crop, it provides a 35mm (FF) equivalent of 32mm.