The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon RF 16mm F2.8 STM and the Sigma 15mm F2.8 EX DG Fisheye 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 F2.8 EX DG Fisheye is the longer of the two lenses at 65mm. The Canon RF 16mm F2.8 STM with a length of 40mm, is 25mm shorter. Besides being longer, the Sigma 15mm F2.8 EX DG Fisheye also has a larger diameter of 74mm compared to the Canon RF 16mm F2.8 STM'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. Canon RF 16mm F2.8 STM weighs 165g, which means it is 205g (55%) lighter than the Sigma 15mm F2.8 EX DG Fisheye which has a weight of 370g.
Lens Mounts
The Canon RF 16mm F2.8 STM has the Canon RF lens mount whereas the Sigma 15mm F2.8 EX DG Fisheye has the Sony Alpha lens mount. Some of the latest released cameras that are compatible with these mounts are Canon R6 V, Canon R6 III and Canon C50 for the Canon RF Mount and Sony A99 II, Sony A68 and Sony A77 II for the Sony Alpha Mount.
Sigma 15mm F2.8 EX DG Fisheye is also available in Canon EF , Nikon F (FX), Pentax KAF and Sigma SA mounts.
Focal Range
Canon RF 16mm F2.8 STM is a prime lens with fixed focal lenght of 16mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of
25.6mm.
On the other hand, the Sigma 15mm F2.8 EX DG Fisheye is a prime lens with fixed focal lenght of 15mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 22.5mm.
