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 Sony E 55-210mm F4.5-6.3 OSS 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 Sony E 55-210mm F4.5-6.3 OSS with a length of 108mm, is 89mm shorter. Besides being longer, the Sigma 100-400mm F5-6.3 OS also has a larger diameter of 86mm compared to the Sony E 55-210mm F4.5-6.3 OSS's 64mm 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. Sony E 55-210mm F4.5-6.3 OSS weighs 345g, 69% (790g) 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 Sony E 55-210mm F4.5-6.3 OSS has a 49mm 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 49mm filters that we recommend for the Sony E 55-210mm F4.5-6.3 OSS:
Lens Mounts
Both the Sigma 100-400mm F5-6.3 OS and the Sony E 55-210mm F4.5-6.3 OSS 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.
Sigma 100-400mm F5-6.3 OS is also available in Leica L and Fujifilm X 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 Sony E 55-210mm F4.5-6.3 OSS has a focal range of 55-210mm and 3.8X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 82.5-315mm when used on a APS-C / DX format camera.