The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 18-50mm F2.8 DC DN C and the Tamron 17-35mm f2.8-4 LD 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 18-50mm F2.8 DC DN C with a length of 75mm, is 12mm shorter. Besides being longer, the Tamron 17-35mm f2.8-4 LD also has a larger diameter of 83mm compared to the Sigma 18-50mm F2.8 DC DN C's 65mm 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 18-50mm F2.8 DC DN C weighs 290g, which means it is 150g (34%) lighter than the Tamron 17-35mm f2.8-4 LD which has a weight of 440g.
Filter Threads
The Sigma 18-50mm F2.8 DC DN C has a filter size of 55mm whereas the Tamron 17-35mm f2.8-4 LD has a 77mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 55mm filters that we recommend you to consider for the Sigma 18-50mm F2.8 DC DN C:
And these are the 77mm filters that we recommend for the Tamron 17-35mm f2.8-4 LD:
Lens Mounts
The Sigma 18-50mm F2.8 DC DN C has the Sony E lens mount whereas the Tamron 17-35mm f2.8-4 LD has the Canon EF lens mount. Some of the latest released cameras that are compatible with these mounts are Sony ZV-E10 II, Sony A6700 and Sony FX30 for the Sony E 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 18-50mm F2.8 DC DN C is also available in the Leica L and Fujifilm X mounts.
Tamron 17-35mm f2.8-4 LD is also available in Nikon F (FX) mount.
Focal Range
Sigma 18-50mm F2.8 DC DN C has a focal range of 18-50mm and
2.8X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
27-75mm when used on a APS-C / DX format camera.
On the other hand, the 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 1.6x crop, it provides a 35mm (FF) equivalent of 27.2 - 56mm.
