The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Leica SL 21mm F2 ASPH and the Sigma 20mm F1.4 DG DN A 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 F1.4 DG DN A is the longer of the two lenses at 111mm. The Leica SL 21mm F2 ASPH with a length of 102mm, is 9mm shorter. Besides being longer, the Sigma 20mm F1.4 DG DN A also has a larger diameter of 88mm compared to the Leica SL 21mm F2 ASPH's 73mm diameter.
Below you can find a scaled side-by-side image of Leica SL 21mm F2 ASPH and Sigma 20mm F1.4 DG DN A to get a better idea of how their sizes compare in real life.
Comparison image of the Leica SL 21mm F2 ASPH and the Sigma 20mm F1.4 DG DN A Size and Weight 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. Sigma 20mm F1.4 DG DN A weighs 635g, 19% (154g) lighter than the Leica SL 21mm F2 ASPH's weight of 789g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Leica L Mount for size comparison purposes.
Wideangle Leica L Mount
Filter Threads
The Leica SL 21mm F2 ASPH has a filter size of 67mm whereas the Sigma 20mm F1.4 DG DN A has a 82mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 67mm filters that we recommend you to consider for the Leica SL 21mm F2 ASPH:
And these are the 82mm filters that we recommend for the Sigma 20mm F1.4 DG DN A:
Lens Mounts
Both the Leica SL 21mm F2 ASPH and the Sigma 20mm F1.4 DG DN A 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 .
Sony E mount.
Focal Range
Leica SL 21mm F2 ASPH is a prime lens with fixed focal lenght of 21mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
31.5mm .
On the other hand, the 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 .
