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 28mm F2.8 STM 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 15mm f1.4 DC C is the longer of the two lenses at 63mm. The Canon RF 28mm F2.8 STM with a length of 25mm, is 38mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 69mm.
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. Canon RF 28mm F2.8 STM weighs 120g, 50% (120g) lighter than the Sigma 15mm f1.4 DC C's weight of 240g.
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 28mm F2.8 STM has a 55mm 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 55mm filters that we recommend for the Canon RF 28mm F2.8 STM:
Lens Mounts
Both the Sigma 15mm f1.4 DC C and the Canon RF 28mm F2.8 STM 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 28mm F2.8 STM is a prime lens with fixed focal lenght of 28mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 44.8mm.
