The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 20-40mm F2.8 VXD and the Sony FE 16-35mm F2.8 GM 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. Sony FE 16-35mm F2.8 GM is the longer of the two lenses at 122mm. The Tamron 20-40mm F2.8 VXD with a length of 86mm, is 36mm shorter. Besides being longer, the Sony FE 16-35mm F2.8 GM also has a larger diameter of 89mm compared to the Tamron 20-40mm F2.8 VXD's 74mm diameter.
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Below you can find a scaled side-by-side image of Tamron 20-40mm F2.8 VXD and Sony FE 16-35mm F2.8 GM 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 20-40mm F2.8 VXD weighs 365g, which means it is 315g (46%) lighter than the Sony FE 16-35mm F2.8 GM which has a weight of 680g.
Filter Threads
The Tamron 20-40mm F2.8 VXD has a filter size of 67mm whereas the Sony FE 16-35mm F2.8 GM 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 67mm filters that we recommend you to consider for the Tamron 20-40mm F2.8 VXD:
And these are the 82mm filters that we recommend for the Sony FE 16-35mm F2.8 GM:
Lens Mounts
Both the Tamron 20-40mm F2.8 VXD and the Sony FE 16-35mm F2.8 GM has the same Sony E lens mount. Some of the latest released cameras that are compatible with the Sony E lenses are Sony A9 III, Sony A7C Mark II and Sony A7CR.
Focal Range
Tamron 20-40mm F2.8 VXD has a focal range of 20-40mm and
2.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
30 - 60mm.
On the other hand, the Sony FE 16-35mm F2.8 GM has a focal range of 16-35mm and 2.2X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 24 - 52.5mm.