The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 150-600mm f5-6.3 VC and the Sigma 120-300mm F2.8 DG OS 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 DG OS HSM is the longer of the two lenses at 291mm. The Tamron 150-600mm f5-6.3 VC with a length of 258mm, is 33mm shorter. Besides being longer, the Sigma 120-300mm F2.8 DG OS HSM also has a larger diameter of 124mm compared to the Tamron 150-600mm f5-6.3 VC's 106mm 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 150-600mm f5-6.3 VC weighs 1951g, which means it is 999g (33%) lighter than the Sigma 120-300mm F2.8 DG OS HSM which has a weight of 2950g.
Filter Threads
The Tamron 150-600mm f5-6.3 VC has a filter size of 95mm whereas the Sigma 120-300mm F2.8 DG OS 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 95mm filters that we recommend you to consider for the Tamron 150-600mm f5-6.3 VC:
And these are the 105mm filters that we recommend for the Sigma 120-300mm F2.8 DG OS HSM:
Lens Mounts
Both the Tamron 150-600mm f5-6.3 VC and the Sigma 120-300mm F2.8 DG OS HSM 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.
Tamron 150-600mm f5-6.3 VC is also available in Canon EF and Sony Alpha mounts.
Sigma 120-300mm F2.8 DG OS HSM is also available in Canon EF and Sigma SA mounts.
Focal Range
Tamron 150-600mm f5-6.3 VC has a focal range of 150-600mm 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
225 - 900mm.
On the other hand, the Sigma 120-300mm F2.8 DG OS 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.