The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 15mm f1.4 DC C and the Canon RF 20mm F1.4 L VCM 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. Canon RF 20mm F1.4 L VCM is the longer of the two lenses at 99mm. The Sigma 15mm f1.4 DC C with a length of 63mm, is 36mm shorter. Besides being longer, the Canon RF 20mm F1.4 L VCM also has a larger diameter of 76mm compared to the Sigma 15mm f1.4 DC C's 69mm 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. Sigma 15mm f1.4 DC C weighs 240g, which means it is 260g (52%) lighter than the Canon RF 20mm F1.4 L VCM which has a weight of 500g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Canon RF Mount for size comparison purposes.
Wideangle Lenses in Canon RF Mount for Size Comparison
Filter Threads
The Sigma 15mm f1.4 DC C has a filter size of 58mm whereas the Canon RF 20mm F1.4 L VCM has a 67mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 58mm filters that we recommend you to consider for the Sigma 15mm f1.4 DC C:
And these are the 67mm filters that we recommend for the Canon RF 20mm F1.4 L VCM:
Lens Mounts
Both the Sigma 15mm f1.4 DC C and the Canon RF 20mm F1.4 L VCM has the same Canon RF lens mount. Some of the latest released cameras that are compatible with the Canon RF lenses are Canon R50 V, Canon R100 and Canon R50.
Sigma 15mm f1.4 DC C is also available in the Fujifilm X and Sony E mounts.
Focal Range
Sigma 15mm f1.4 DC C is a prime lens with fixed focal lenght of 15mm which has an effective (full-frame 35mm equivalent) focal range of
24mm when used on a APS-C / DX format camera.
On the other hand, the Canon RF 20mm F1.4 L VCM 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.
