The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 17-35mm f2.8-4 LD and the Sigma 8mm F3.5 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. Tamron 17-35mm f2.8-4 LD is the longer of the two lenses at 87mm. The Sigma 8mm F3.5 EX DG Fisheye with a length of 69mm, is 18mm shorter. Besides being longer, the Tamron 17-35mm f2.8-4 LD also has a larger diameter of 83mm compared to the Sigma 8mm F3.5 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 8mm F3.5 EX DG Fisheye weighs 400g, 9% (40g) lighter than the Tamron 17-35mm f2.8-4 LD's weight of 440g.
Lens Mounts
Both the Tamron 17-35mm f2.8-4 LD and the Sigma 8mm F3.5 EX DG Fisheye has the same Nikon F (FX) lens mount. Some of the latest released cameras that are compatible with the Nikon F (FX) lenses are Nikon D6, Nikon D780 and Nikon D3500.
Tamron 17-35mm f2.8-4 LD is also available in the Canon EF mount.
Sigma 8mm F3.5 EX DG Fisheye is also available in Canon EF and Sigma SA mounts.
Focal Range
Tamron 17-35mm f2.8-4 LD has a focal range of 17-35mm and
2.1X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
25.5 - 52.5mm.
On the other hand, the Sigma 8mm F3.5 EX DG Fisheye is a prime lens with fixed focal lenght of 8mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 12mm.
