The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Voigtlander 58mm F1.4 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 58mm F1.4 SL II is the longer of the two lenses at 48mm. The Pentax 40mm F2.8 L with a length of 15mm, is 33mm shorter. Besides being longer, the Voigtlander 58mm F1.4 SL II also has a larger diameter of 64mm compared to the Pentax 40mm F2.8 L'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. Pentax 40mm F2.8 L weighs 90g, 71% (230g) lighter than the Voigtlander 58mm F1.4 SL II's weight of 320g.
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 58mm F1.4 SL II has a filter size of 58mm 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 58mm filters that we recommend you to consider for the Voigtlander 58mm F1.4 SL II:
And these are the 49mm filters that we recommend for the Pentax 40mm F2.8 L:
Lens Mounts
Both the Voigtlander 58mm F1.4 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 58mm F1.4 SL II is also available in Nikon F (FX) mount.
Pentax 40mm F2.8 L is also available in Pentax KAF mount.
Focal Range
Voigtlander 58mm F1.4 SL II is a prime lens with fixed focal lenght of 58mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
87mm.
On the other hand, the Pentax 40mm F2.8 L is a prime lens with fixed focal lenght of 40mm which has an effective (full-frame 35mm equivalent) focal range of 60mm when used on a APS-C / DX format camera.