The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Nikon AF-S 120-300mm F2.8E FL ED SR VR and the Sigma 70-300mm F4-5.6 DG 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. Nikon AF-S 120-300mm F2.8E FL ED SR VR is the longer of the two lenses at 304mm. The Sigma 70-300mm F4-5.6 DG with a length of 122mm, is 182mm shorter. Besides being longer, the Nikon AF-S 120-300mm F2.8E FL ED SR VR also has a larger diameter of 128mm compared to the Sigma 70-300mm F4-5.6 DG's 77mm 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. Sigma 70-300mm F4-5.6 DG weighs 550g, 83% (2700g) lighter than the Nikon AF-S 120-300mm F2.8E FL ED SR VR's weight of 3250g.
Below you can find the dimension and weight table of the Telephoto Zoom Lenses in Nikon F (FX) Mount for size comparison purposes.
Telephoto Lenses in Nikon F (FX) Mount for Size Comparison
Filter Threads
The Nikon AF-S 120-300mm F2.8E FL ED SR VR has a filter size of 112mm whereas the Sigma 70-300mm F4-5.6 DG has a 58mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 112mm filters that we recommend you to consider for the Nikon AF-S 120-300mm F2.8E FL ED SR VR:
And these are the 58mm filters that we recommend for the Sigma 70-300mm F4-5.6 DG:
Lens Mounts
Both the Nikon AF-S 120-300mm F2.8E FL ED SR VR and the Sigma 70-300mm F4-5.6 DG has the same Nikon F (FX) lens mount. Some of the latest released cameras that are compatible with the Nikon F (FX) lenses are Nikon D6, Nikon D780 and Nikon D3500.
Sigma 70-300mm F4-5.6 DG is also available in Canon EF , Nikon F (FX), Pentax KAF, Sony Alpha, Sigma SA, Canon EF, Pentax KAF, Sony Alpha and Sigma SA mounts.
Focal Range
Nikon AF-S 120-300mm F2.8E FL ED SR VR 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.
On the other hand, the Sigma 70-300mm F4-5.6 DG has a focal range of 70-300mm and 4.3X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 105 - 450mm.