The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 20mm F1.4 DG DN A and the Sony FE 14mm F1.8 GM 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 20mm F1.4 DG DN A is the longer of the two lenses at 111mm. The Sony FE 14mm F1.8 GM with a length of 100mm, is 11mm shorter. Besides being longer, the Sigma 20mm F1.4 DG DN A also has a larger diameter of 88mm compared to the Sony FE 14mm F1.8 GM's 83mm diameter.
Below you can find a scaled side-by-side image of Sigma 20mm F1.4 DG DN A and Sony FE 14mm F1.8 GM to get a better idea of how their sizes compare in real life.
Comparison image of the Sigma 20mm F1.4 DG DN A and the Sony FE 14mm F1.8 GM Size and Weight 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. Sony FE 14mm F1.8 GM weighs 460g, 27% (175g) lighter than the Sigma 20mm F1.4 DG DN A's weight of 635g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Sony E Mount for size comparison purposes.
Wideangle Prime Lenses in Sony E Mount for Size Comparison
Lens Mounts
Both the Sigma 20mm F1.4 DG DN A and the Sony FE 14mm F1.8 GM has the same Sony E lens mount. Some of the latest released cameras that are compatible with the Sony E lenses are Sony A7R V, Sony FX30 and Sony A7 IV.
Sigma 20mm F1.4 DG DN A is also available in Leica L mount.
Focal Range
Sigma 20mm F1.4 DG DN A is a prime lens with fixed focal lenght of 20mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 36mm.
Sony FE 14mm F1.8 GM is a prime lens with fixed focal lenght of 14mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 21mm.