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 Olympus M 25mm F1.8 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 Olympus M 25mm F1.8 with a length of 41mm, is 32mm shorter. Besides being longer, the Sigma 30mm F1.4 C also has a larger diameter of 65mm compared to the Olympus M 25mm F1.8's 56mm diameter.
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. Olympus M 25mm F1.8 weighs 136g, 48% (129g) lighter than the Sigma 30mm F1.4 C's 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 Sigma 30mm F1.4 C and the Olympus M 25mm F1.8 has the same Micro Four Thirds lens mount. Some of the latest released cameras that are compatible with the Micro Four Thirds lenses are , and .
Sigma 30mm F1.4 C is also available in Sony E and Fujifilm X mounts.
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. Olympus M 25mm F1.8 is a prime lens with fixed focal lenght of 25mm which has an effective (full-frame 35mm equivalent) focal range of 50mm when used on a FourThirds format camera.