The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 100-400mm F5-6.3 OS and the Tamron AF 28-200mm f3.8-5.6 XR 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. Sigma 100-400mm F5-6.3 OS is the longer of the two lenses at 197mm. The Tamron AF 28-200mm f3.8-5.6 XR with a length of 75mm, is 122mm shorter. Besides being longer, the Sigma 100-400mm F5-6.3 OS also has a larger diameter of 86mm compared to the Tamron AF 28-200mm f3.8-5.6 XR's 71mm 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. Tamron AF 28-200mm f3.8-5.6 XR weighs 354g, 68% (781g) lighter than the Sigma 100-400mm F5-6.3 OS's weight of 1135g.
Filter Threads
The Sigma 100-400mm F5-6.3 OS has a filter size of 67mm whereas the Tamron AF 28-200mm f3.8-5.6 XR has a 62mm 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 Sigma 100-400mm F5-6.3 OS:
And these are the 62mm filters that we recommend for the Tamron AF 28-200mm f3.8-5.6 XR:
Lens Mounts
The Sigma 100-400mm F5-6.3 OS has the Sony E lens mount whereas the Tamron AF 28-200mm f3.8-5.6 XR has the Sony Alpha lens mount. Some of the latest released cameras that are compatible with these mounts are Sony FX5, Sony A7R VI and Sony A7 V for the Sony E Mount and Sony A99 II, Sony A68 and Sony A77 II for the Sony Alpha Mount.
Sigma 100-400mm F5-6.3 OS is also available in the Leica L and Fujifilm X mounts.
Tamron AF 28-200mm f3.8-5.6 XR is also available in Canon EF , Nikon F (FX) and Pentax KAF mounts.
Focal Range
Sigma 100-400mm F5-6.3 OS 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 AF 28-200mm f3.8-5.6 XR has a focal range of 28-200mm and 7.1X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 42 - 300mm.
