The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony FE 100-400mm F4.5-5.6 and the Tamron 200-500mm f5-6.3 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 200-500mm f5-6.3 LD is the longer of the two lenses at 227mm. The Sony FE 100-400mm F4.5-5.6 with a length of 205mm, is 22mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 94mm.
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 200-500mm f5-6.3 LD weighs 1237g, 11% (158g) lighter than the Sony FE 100-400mm F4.5-5.6's weight of 1395g.
Filter Threads
The Sony FE 100-400mm F4.5-5.6 has a filter size of 77mm whereas the Tamron 200-500mm f5-6.3 LD has a 86mm 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 Sony FE 100-400mm F4.5-5.6:
And these are the 86mm filters that we recommend for the Tamron 200-500mm f5-6.3 LD:
Lens Mounts
The Sony FE 100-400mm F4.5-5.6 has the Sony E lens mount whereas the Tamron 200-500mm f5-6.3 LD has the Sony Alpha lens mount. Some of the latest released cameras that are compatible with these mounts are Sony A9 III, Sony A7C Mark II and Sony A7CR for the Sony E Mount and Sony A99 II, Sony A68 and Sony A77 II for the Sony Alpha Mount.
Tamron 200-500mm f5-6.3 LD is also available in Canon EF and Nikon F (FX) mounts.
Focal Range
Sony FE 100-400mm F4.5-5.6 has a focal range of 100-400mm and
4.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
150 - 600mm.
On the other hand, the Tamron 200-500mm f5-6.3 LD has a focal range of 200-500mm and 2.5X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 300 - 750mm.