The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 30mm F1.4 C and the Zeiss Touit 50mm f2.8 for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Zeiss Touit 50mm f2.8 is the longer of the two lenses at 91mm. The Sigma 30mm F1.4 C with a length of 73mm is 18mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 65mm.
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. Sigma 30mm F1.4 C weighs 265g, which means it is 25g (8%) lighter than the Zeiss Touit 50mm f2.8 which has a weight of 290g.
Below you can find the dimension and weight table of the 'Standard Prime Lenses in Fujifilm X Mount for size comparison purposes.
Standard Prime Lenses in Fujifilm X Mount for Size Comparison
Lens Mounts
Both Sigma 30mm F1.4 C and Zeiss Touit 50mm f2.8 has the same Fujifilm X lens mount. Some of the latest released cameras that are compatible with the Fujifilm X lenses are Fujifilm X-T5, Fujifilm X-H2 and Fujifilm X-H2S.
Sigma 30mm F1.4 C is also available in Sony E and Micro Four Thirds mounts.
Zeiss Touit 50mm f2.8 is also available in Sony E mount.
Focal Range
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. Zeiss Touit 50mm f2.8 is a prime lens with fixed focal lenght of 50mm which has an effective (full-frame 35mm equivalent) focal range of 75mm when used on a APS-C / DX format camera.