The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon 50mm f1.2L USM and the Voigtlander 40mm F2 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. Canon 50mm f1.2L USM is the longer of the two lenses at 66mm. The Voigtlander 40mm F2 SL II with a length of 25mm, is 41mm shorter. Besides being longer, the Canon 50mm f1.2L USM also has a larger diameter of 86mm compared to the Voigtlander 40mm F2 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 40mm F2 SL II weighs 200g, 65% (380g) lighter than the Canon 50mm f1.2L USM's weight of 580g.
Below you can find the dimension and weight table of the Standard Prime Lenses in Canon EF Mount for size comparison purposes.
Standard Lenses in Canon EF Mount for Size Comparison
Filter Threads
The Canon 50mm f1.2L USM has a filter size of 72mm whereas the Voigtlander 40mm F2 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 72mm filters that we recommend you to consider for the Canon 50mm f1.2L USM:
And these are the 52mm filters that we recommend for the Voigtlander 40mm F2 SL II:
Lens Mounts
Both the Canon 50mm f1.2L USM and the Voigtlander 40mm F2 SL II has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Canon 1D X III, Canon 6D MII and Canon 5D MIV.
Voigtlander 40mm F2 SL II is also available in Nikon F (FX) and Pentax KAF mounts.
Focal Range
Canon 50mm f1.2L USM is a prime lens with fixed focal lenght of 50mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of
80mm.
On the other hand, the Voigtlander 40mm F2 SL II is a prime lens with fixed focal lenght of 40mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 64mm.