The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang 20mm F1.8 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. Samyang 20mm F1.8 is the longer of the two lenses at 88mm. The Voigtlander 20mm F3.5 SL II with a length of 29mm, is 59mm shorter. Besides being longer, the Samyang 20mm F1.8 also has a larger diameter of 83mm 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, 58% (292g) lighter than the Samyang 20mm F1.8's weight of 497g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Pentax KAF Mount for size comparison purposes.
Ultra-Wideangle Lenses in Pentax KAF Mount for Size Comparison
The Samyang 20mm F1.8 has a filter size of 77mm 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 77mm filters that we recommend you to consider for the Samyang 20mm F1.8:
And these are the 52mm filters that we recommend for the Voigtlander 20mm F3.5 SL II:
Both the Samyang 20mm F1.8 and the Voigtlander 20mm F3.5 SL II has the same Pentax KAF lens mount. Some of the latest released cameras that are compatible with the Pentax KAF lenses are Pentax K-3 III Monochrome, Pentax KF and Pentax K-3 III.
Samyang 20mm F1.8 is also available in Canon EF , Canon EF-M, Fujifilm X, Micro Four Thirds, Nikon F (FX), Samsung NX, Sony Alpha and Sony E mounts.
Voigtlander 20mm F3.5 SL II is also available in Canon EF and Nikon F (FX) mounts.
Both lenses have the same focal range of 20mm
but while Samyang 20mm F1.8 has the fastest aperture of F1.8
, the Voigtlander 20mm F3.5 SL II's widest aperture value is F3.5