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 Sigma 30mm F1.4 DC HSM for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Sigma 30mm F1.4 DC HSM is the longer of the two lenses at 63mm. The Voigtlander 40mm F2 SL II with a length of 25mm is 38mm shorter. Besides being longer, the Sigma 30mm F1.4 DC HSM also has a larger diameter of 74mm compared to Voigtlander 40mm F2 SL II's 63mm diameter.
Weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Voigtlander 40mm F2 SL II weighs 200g, which means it is 235g (54%) lighter than the Sigma 30mm F1.4 DC HSM which has a weight of 435g.
Below you can find the dimension and weight table of the 'Standard Prime Lenses in Canon EF Mount for size comparison purposes.
Standard Prime Lenses in Canon EF Mount for Size Comparison
Lens Mounts
Both Voigtlander 40mm F2 SL II and Sigma 30mm F1.4 DC HSM 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.
Sigma 30mm F1.4 DC HSM is also available in Nikon F (DX) and Sigma SA mounts.
Focal Range
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 an 35mm (FF) equivalent of 64mm.
Sigma 30mm F1.4 DC HSM is a prime lens with fixed focal lenght of 30mm which has an effective (full-frame 35mm equivalent) focal range of 48mm when used on a APS-C / DX format camera.