The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax D FA 70-200mm F2.8ED and the Sigma 300mm F2.8 APO 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 300mm F2.8 APO EX DG HSM is the longer of the two lenses at 215mm. The Pentax D FA 70-200mm F2.8ED with a length of 203mm, is 12mm shorter. Besides being longer, the Sigma 300mm F2.8 APO EX DG HSM also has a larger diameter of 119mm compared to the Pentax D FA 70-200mm F2.8ED's 92mm 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. Pentax D FA 70-200mm F2.8ED weighs 1755g, which means it is 645g (26%) lighter than the Sigma 300mm F2.8 APO EX DG HSM which has a weight of 2400g.
Filter Threads
The Pentax D FA 70-200mm F2.8ED has a filter size of 77mm whereas the Sigma 300mm F2.8 APO EX DG HSM has a 46mm 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 Pentax D FA 70-200mm F2.8ED:
And these are the 46mm filters that we recommend for the Sigma 300mm F2.8 APO EX DG HSM:
Lens Mounts
The Pentax D FA 70-200mm F2.8ED has the Pentax KAF3 lens mount whereas the Sigma 300mm F2.8 APO EX DG HSM has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF3 Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Sigma 300mm F2.8 APO EX DG HSM is also available in Canon EF , Nikon F (FX), Sony Alpha and Sigma SA mounts.
Focal Range
Pentax D FA 70-200mm F2.8ED 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 300mm F2.8 APO EX DG HSM 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.
