The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony FE 300mm f2.8 GM and the Sigma 120-300mm F2.8 EX DG HSM 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 120-300mm F2.8 EX DG HSM is the longer of the two lenses at 271mm. The Sony FE 300mm f2.8 GM with a length of 264mm, is 7mm shorter. On the other hand, the Sony FE 300mm f2.8 GM has a larger diameter of 124mm compared to the Sigma 120-300mm F2.8 EX DG HSM's 113mm 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 FE 300mm f2.8 GM weighs 1470g, which means it is 1130g (43%) lighter than the Sigma 120-300mm F2.8 EX DG HSM which has a weight of 2600g.
Filter Threads
The Sony FE 300mm f2.8 GM has a filter size of 41mm whereas the Sigma 120-300mm F2.8 EX DG HSM has a 105mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 41mm filters that we recommend you to consider for the Sony FE 300mm f2.8 GM:
And these are the 105mm filters that we recommend for the Sigma 120-300mm F2.8 EX DG HSM:
Lens Mounts
The Sony FE 300mm f2.8 GM has the Sony E lens mount whereas the Sigma 120-300mm F2.8 EX DG HSM has the Nikon F (FX) 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 Nikon D6, Nikon D780 and Nikon D3500 for the Nikon F (FX) Mount.
Sigma 120-300mm F2.8 EX DG HSM is also available in Canon EF and Sigma SA mounts.
Focal Range
Sony FE 300mm f2.8 GM is a prime lens with fixed focal lenght of 300mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
450mm.
On the other hand, the Sigma 120-300mm F2.8 EX DG HSM has a focal range of 120-300mm 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 180 - 450mm.
