The type of photography that you are planning to use is an important decision factor. Here we have evaluated the OM ED 20mm F1.4 Pro and the Sigma 30mm F1.4 C for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is an important deciding factor when comparing two lenses. Sigma 30mm F1.4 C is the longer of the two lenses at 73mm. The OM ED 20mm F1.4 Pro with a length of 62mm, is 11mm shorter. Besides being longer, the Sigma 30mm F1.4 C also has a larger diameter of 65mm compared to the OM ED 20mm F1.4 Pro's 63mm diameter.
Below you can find a scaled side-by-side image of OM ED 20mm F1.4 Pro and Sigma 30mm F1.4 C to get a better idea of how their sizes compare in real life.
The 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. OM ED 20mm F1.4 Pro weighs 247g, which means it is 18g (6%) lighter than the Sigma 30mm F1.4 C which has a weight of 265g.
Below you can find the dimension and weight table of the Standard Prime Lenses in Micro Four Thirds Mount for size comparison purposes.
Standard Prime Lenses in Micro Four Thirds Mount for Size Comparison
Both the OM ED 20mm F1.4 Pro and the Sigma 30mm F1.4 C has the same Micro Four Thirds lens mount. Some of the latest released cameras that are compatible with the Micro Four Thirds lenses are OM System OM-5, Panasonic GH6 and OM System OM-1.
Sigma 30mm F1.4 C is also available in Sony E and Fujifilm X mounts.
OM ED 20mm F1.4 Pro is a prime lens with fixed focal lenght of 20mm which has an effective (full-frame 35mm equivalent) focal range of 40mm when used on a FourThirds format camera. Sigma 30mm F1.4 C is a prime lens with fixed focal lenght of 30mm which has an effective (full-frame 35mm equivalent) focal range of 45mm when used on a APS-C / DX format camera.