The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony FE 20mm F1.8 G 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. Sony FE 20mm F1.8 G is the longer of the two lenses at 85mm. The Voigtlander 20mm F3.5 SL II with a length of 29mm, is 56mm shorter. Besides being longer, the Sony FE 20mm F1.8 G also has a larger diameter of 74mm 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. Voigtlander 20mm F3.5 SL II weighs 205g, 45% (168g) lighter than the Sony FE 20mm F1.8 G's weight of 373g.
Filter Threads
The Sony FE 20mm F1.8 G has a filter size of 67mm whereas the Voigtlander 20mm F3.5 SL II has a 52mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 67mm filters that we recommend you to consider for the Sony FE 20mm F1.8 G:
And these are the 52mm filters that we recommend for the Voigtlander 20mm F3.5 SL II:
Lens Mounts
The Sony FE 20mm F1.8 G has the Sony E lens mount whereas the Voigtlander 20mm F3.5 SL II has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Sony A9 III, Sony A7C Mark II and Sony A7CR for the Sony E Mount and Pentax K-3 III Monochrome, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Voigtlander 20mm F3.5 SL II is also available in Canon EF and Nikon F (FX) mounts.
Focal Range
Both lenses have the same focal range of
20mm but while Sony FE 20mm F1.8 G has the fastest aperture of
F1.8, the Voigtlander 20mm F3.5 SL II's widest aperture value is
F3.5.