The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Irix 11mm F4 and the Sigma 20mm F1.4 DG HSM 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 HSM A is the longer of the two lenses at 130mm. The Irix 11mm F4 with a length of 118mm, is 12mm shorter. On the other hand, the Irix 11mm F4 has a larger diameter of 103mm compared to the Sigma 20mm F1.4 DG HSM A's 91mm diameter.
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Below you can find a scaled side-by-side image of Irix 11mm F4 and Sigma 20mm F1.4 DG HSM A to get a better idea of how their sizes compare in real life.
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. Irix 11mm F4 weighs 790g, which means it is 160g (16%) lighter than the Sigma 20mm F1.4 DG HSM A which has a weight of 950g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Canon EF Mount for size comparison purposes.
Ultra-Wideangle Lenses in Canon EF Mount for Size Comparison
Lens Mounts
Both the Irix 11mm F4 and the Sigma 20mm F1.4 DG HSM A has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Canon 1D X III, Canon 6D MII and Canon 5D MIV.
Irix 11mm F4 is also available in Nikon F (FX) and Pentax KAF3 mounts.
Sigma 20mm F1.4 DG HSM A is also available in Nikon F (FX) , Sigma SA and Leica L mounts.
Focal Range
Irix 11mm F4 is a prime lens with fixed focal lenght of 11mm.
On the other hand, the Sigma 20mm F1.4 DG HSM A is a prime lens with fixed focal lenght of 20mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 32mm.