The type of photography that you are planning to use is an important decision factor. Here we have evaluated the AstrHori 6mm f2.8 and the Sigma 20mm F2 DG DN C for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is a crucial factor to consider when comparing two lenses. Sigma 20mm F2 DG DN C is the longer of the two lenses at 72mm. The AstrHori 6mm f2.8 with a length of 61mm, is 11mm shorter. Besides being longer, the Sigma 20mm F2 DG DN C also has a larger diameter of 70mm compared to the AstrHori 6mm f2.8's 65mm diameter.
The weight of a lens is equally significant as its external dimensions, particularly if you intend to handhold your camera and lens combination for extended periods. AstrHori 6mm f2.8 weighs 340g, which means it is 30g (8%) lighter than the Sigma 20mm F2 DG DN C which has a weight of 370g.
Below you can find the dimension and weight table of the Wideangle Fisheye Prime Lenses in Leica L Mount for size comparison purposes.
Ultra-Wideangle Lenses in Leica L Mount for Size Comparison
Lens Mounts
Both the AstrHori 6mm f2.8 and the Sigma 20mm F2 DG DN C has the same Leica L lens mount. Some of the latest released cameras that are compatible with the Leica L lenses are Leica SL3-P, Panasonic S1 II and Panasonic S1 IIE.
AstrHori 6mm f2.8 is also available in the Sony E , Nikon Z and Canon RF mounts.
Sigma 20mm F2 DG DN C is also available in Sony E mount.
Focal Range
AstrHori 6mm f2.8 is a prime lens with fixed focal lenght of 6mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
9mm.
On the other hand, the Sigma 20mm F2 DG DN C 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 30mm.
