The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Voigtlander 40mm F2 SL II and the Pentax 40mm F2.8 L 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 40mm F2 SL II is the longer of the two lenses at 25mm. The Pentax 40mm F2.8 L with a length of 15mm, is 10mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 63mm.
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. Pentax 40mm F2.8 L weighs 80g, 60% (120g) lighter than the Voigtlander 40mm F2 SL II's weight of 200g.
Below you can find the dimension and weight table of the Standard Prime Lenses in Pentax KAF Mount for size comparison purposes.
Standard Lenses in Pentax KAF Mount for Size Comparison
Filter Threads
The Voigtlander 40mm F2 SL II has a filter size of 52mm whereas the Pentax 40mm F2.8 L has a 49mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 52mm filters that we recommend you to consider for the Voigtlander 40mm F2 SL II:
And these are the 49mm filters that we recommend for the Pentax 40mm F2.8 L:
Lens Mounts
Both the Voigtlander 40mm F2 SL II and the Pentax 40mm F2.8 L 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.
Voigtlander 40mm F2 SL II is also available in Canon EF and Nikon F (FX) mounts.
Pentax 40mm F2.8 L is also available in Pentax KAF mount.
Focal Range
Both lenses have the same focal range of
40mm but while Voigtlander 40mm F2 SL II has the fastest aperture of
F2.0, the Pentax 40mm F2.8 L's widest aperture value is
F2.8.