The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 300-600mm f4 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 300-600mm f4 is the longer of the two lenses at 470mm. The Sigma 120-300mm F2.8 DG OS HSM with a length of 291mm, is 179mm shorter. Besides being longer, the Sigma 300-600mm f4 also has a larger diameter of 167mm compared to the Sigma 120-300mm F2.8 DG OS HSM's 124mm 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 120-300mm F2.8 DG OS HSM weighs 2950g, 25% (1020g) lighter than the Sigma 300-600mm f4's weight of 3970g.
Filter Threads
The Sigma 300-600mm f4 has a filter size of 41mm 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 41mm filters that we recommend you to consider for the Sigma 300-600mm f4:
And these are the 105mm filters that we recommend for the Sigma 120-300mm F2.8 DG OS HSM:
Lens Mounts
The Sigma 300-600mm f4 has the Sony E lens mount whereas the Sigma 120-300mm F2.8 DG OS HSM has the Sigma SA 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 Sigma Quattro, Sigma Quattro H and Sigma SD1 Merrill for the Sigma SA Mount.
Sigma 300-600mm f4 is also available in the Leica L mount.
Sigma 120-300mm F2.8 DG OS HSM is also available in Canon EF and Nikon F (FX) mounts.
Focal Range
Sigma 300-600mm f4 has a focal range of 300-600mm and
2.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
450 - 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 .
