The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 70-200mm F2.8 EX DG HSM II and the Sigma 50-200mm F4-5.6 DC 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 70-200mm F2.8 EX DG HSM II is the longer of the two lenses at 184mm. The Sigma 50-200mm F4-5.6 DC OS HSM with a length of 102mm, is 82mm shorter. Besides being longer, the Sigma 70-200mm F2.8 EX DG HSM II also has a larger diameter of 87mm compared to the Sigma 50-200mm F4-5.6 DC OS HSM's 74mm 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 50-200mm F4-5.6 DC OS HSM weighs 420g, 69% (970g) lighter than the Sigma 70-200mm F2.8 EX DG HSM II's weight of 1390g.
Below you can find the dimension and weight table of the Telephoto Zoom Lenses in Pentax KAF3 Mount for size comparison purposes.
Telephoto Lenses in Pentax KAF3 Mount for Size Comparison
Filter Threads
The Sigma 70-200mm F2.8 EX DG HSM II has a filter size of 77mm whereas the Sigma 50-200mm F4-5.6 DC OS HSM has a 55mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 77mm filters that we recommend you to consider for the Sigma 70-200mm F2.8 EX DG HSM II:
And these are the 55mm filters that we recommend for the Sigma 50-200mm F4-5.6 DC OS HSM:
Lens Mounts
Both the Sigma 70-200mm F2.8 EX DG HSM II and the Sigma 50-200mm F4-5.6 DC OS HSM has the same Pentax KAF3 lens mount. Some of the latest released cameras that are compatible with the Pentax KAF3 lenses are , and .
Sigma 70-200mm F2.8 EX DG HSM II is also available in the Canon EF , Four Thirds, Sony Alpha, Sigma SA and Nikon F (FX) mounts.
Sigma 50-200mm F4-5.6 DC OS HSM is also available in Canon EF , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Focal Range
Sigma 70-200mm F2.8 EX DG HSM II has a focal range of 70-200mm and
2.9X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
105 - 300mm.
On the other hand, the Sigma 50-200mm F4-5.6 DC OS HSM has a focal range of 50-200mm and 4.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 75-300mm when used on a APS-C / DX format camera.
