The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 70-300 F4.5-6.3 Di III and the Tamron 70-180mm F2.8 Di 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 70-180mm F2.8 Di is the longer of the two lenses at 149mm. The Tamron 70-300 F4.5-6.3 Di III with a length of 148mm, is 1mm shorter. Besides being longer, the Tamron 70-180mm F2.8 Di also has a larger diameter of 81mm compared to the Tamron 70-300 F4.5-6.3 Di III's 77mm diameter.
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Below you can find a scaled side-by-side image of Tamron 70-300 F4.5-6.3 Di III and Tamron 70-180mm F2.8 Di 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 70-300 F4.5-6.3 Di III weighs 545g, which means it is 270g (33%) lighter than the Tamron 70-180mm F2.8 Di which has a weight of 815g.
Below you can find the dimension and weight table of the Telephoto Zoom Lenses in Sony E Mount for size comparison purposes.
Telephoto Lenses in Sony E Mount for Size Comparison
Filter Threads
Both the Tamron 70-300 F4.5-6.3 Di III and the Tamron 70-180mm F2.8 Di have the same Filter thread size of 67mm.
Below are links to the 67mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Tamron 70-300 F4.5-6.3 Di III and the Tamron 70-180mm F2.8 Di 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 70-300 F4.5-6.3 Di III has a focal range of 70-300mm and
4.3X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
105 - 450mm.
On the other hand, the Tamron 70-180mm F2.8 Di has a focal range of 70-180mm and 2.6X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 105 - 270mm.