The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 18-35mm F1.8 DC HSM and the Tamron 15-30mm f2.8 VC USD 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 15-30mm f2.8 VC USD is the longer of the two lenses at 145mm. The Sigma 18-35mm F1.8 DC HSM with a length of 121mm, is 24mm shorter. Besides being longer, the Tamron 15-30mm f2.8 VC USD also has a larger diameter of 98mm compared to the Sigma 18-35mm F1.8 DC HSM's 78mm diameter.
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Below you can find a scaled side-by-side image of Sigma 18-35mm F1.8 DC HSM and Tamron 15-30mm f2.8 VC USD to get a better idea of how their sizes compare in real life.
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 18-35mm F1.8 DC HSM weighs 810g, which means it is 290g (26%) lighter than the Tamron 15-30mm f2.8 VC USD which has a weight of 1100g.
Lens Mounts
Both the Sigma 18-35mm F1.8 DC HSM and the Tamron 15-30mm f2.8 VC USD has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Canon T8i, Canon 90D and Canon SL3.
Sigma 18-35mm F1.8 DC HSM is also available in Pentax KAF , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Tamron 15-30mm f2.8 VC USD is also available in Nikon F (FX) and Sony Alpha mounts.
Focal Range
Sigma 18-35mm F1.8 DC HSM has a focal range of 18-35mm and
1.9X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
28.8-56mm when used on a APS-C / DX format camera.
On the other hand, the Tamron 15-30mm f2.8 VC USD has a focal range of 15-30mm and 2.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 24 - 48mm.