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 70-350mm F4.5-6.3 G 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 70-350mm F4.5-6.3 G with a length of 142mm, is 55mm shorter. Besides being longer, the Sigma 100-400mm F5-6.3 OS also has a larger diameter of 86mm compared to the Sony E 70-350mm F4.5-6.3 G's 77mm diameter.
Below you can find a scaled side-by-side image of Sigma 100-400mm F5-6.3 OS and Sony E 70-350mm F4.5-6.3 G to get a better idea of how their sizes compare in real life.
Comparison image of the Sigma 100-400mm F5-6.3 OS and the Sony E 70-350mm F4.5-6.3 G Size and Weight 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 70-350mm F4.5-6.3 G weighs 625g, 44% (510g) lighter than the Sigma 100-400mm F5-6.3 OS's weight of 1135g.
Below you can find the dimension and weight table of the Telephoto Zoom Lenses in Sony E Mount for size comparison purposes.
Super Telephoto Lenses in Sony E Mount for Size Comparison
Filter Threads
Both the Sigma 100-400mm F5-6.3 OS and the Sony E 70-350mm F4.5-6.3 G 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 Sigma 100-400mm F5-6.3 OS and the Sony E 70-350mm F4.5-6.3 G has the same Sony E lens mount . Some of the latest released cameras that are compatible with the Sony E lenses are Sony FX5 , Sony A7R VI and Sony A7 V .
Sigma 100-400mm F5-6.3 OS is also available in the 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 70-350mm F4.5-6.3 G has a focal range of 70-350mm and 5.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 105-525mm when used on a APS-C / DX format camera.