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 Di OSD and the Canon 16-35mm F2.8L III 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 16-35mm F2.8L III is the longer of the two lenses at 128mm. The Tamron 17-35mm F2.8-4 Di OSD with a length of 93mm, is 35mm shorter. Besides being longer, the Canon 16-35mm F2.8L III also has a larger diameter of 89mm compared to the Tamron 17-35mm F2.8-4 Di OSD's 84mm diameter.
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Below you can find a scaled side-by-side image of Tamron 17-35mm F2.8-4 Di OSD and Canon 16-35mm F2.8L III 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. Tamron 17-35mm F2.8-4 Di OSD weighs 460g, which means it is 330g (41%) lighter than the Canon 16-35mm F2.8L III which has a weight of 790g.
Below you can find the dimension and weight table of the Wideangle Zoom Lenses in Canon EF Mount for size comparison purposes.
Ultra-Wideangle Lenses in Canon EF Mount for Size Comparison
Filter Threads
The Tamron 17-35mm F2.8-4 Di OSD has a filter size of 77mm whereas the Canon 16-35mm F2.8L III has a 82mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 77mm filters that we recommend you to consider for the Tamron 17-35mm F2.8-4 Di OSD:
And these are the 82mm filters that we recommend for the Canon 16-35mm F2.8L III:
Lens Mounts
Both the Tamron 17-35mm F2.8-4 Di OSD and the Canon 16-35mm F2.8L III has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Canon 1D X III, Canon 6D MII and Canon 5D MIV.
Tamron 17-35mm F2.8-4 Di OSD is also available in Nikon F (FX) mount.
Focal Range
Tamron 17-35mm F2.8-4 Di OSD 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.
On the other hand, the Canon 16-35mm F2.8L III has a focal range of 16-35mm and 2.2X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 25.6 - 56mm.