The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 15mm F2.8 EX DG Fisheye and the Canon 24-70mm f4L IS USM 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 24-70mm f4L IS USM is the longer of the two lenses at 93mm. The Sigma 15mm F2.8 EX DG Fisheye with a length of 65mm, is 28mm shorter. Besides being longer, the Canon 24-70mm f4L IS USM also has a larger diameter of 83mm compared to the Sigma 15mm F2.8 EX DG Fisheye's 74mm 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 F2.8 EX DG Fisheye weighs 370g, which means it is 230g (38%) lighter than the Canon 24-70mm f4L IS USM which has a weight of 600g.
Lens Mounts
The Sigma 15mm F2.8 EX DG Fisheye has the Sigma SA lens mount whereas the Canon 24-70mm f4L IS USM has the Canon EF lens mount. Some of the latest released cameras that are compatible with these mounts are Sigma Quattro, Sigma Quattro H and Sigma SD1 Merrill for the Sigma SA Mount and Blackmagic URSA 12K LF, Z CAM E2-F6 II 6K and Z CAM E2-S6 II 6K for the Canon EF Mount.
Sigma 15mm F2.8 EX DG Fisheye is also available in the Canon EF , Nikon F (FX), Pentax KAF and Sony Alpha mounts.
Focal Range
Sigma 15mm F2.8 EX DG Fisheye is a prime lens with fixed focal lenght of 15mm.
On the other hand, the Canon 24-70mm f4L IS USM has a focal range of 24-70mm and 2.9X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 38.4 - 112mm.
