The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron AF 70-300mm f4-5.6 LD 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 Tamron AF 70-300mm f4-5.6 LD with a length of 117mm, is 98mm shorter. Besides being longer, the Sigma 300mm F2.8 APO EX DG HSM also has a larger diameter of 119mm compared to the Tamron AF 70-300mm f4-5.6 LD'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. Tamron AF 70-300mm f4-5.6 LD weighs 435g, which means it is 1965g (81%) lighter than the Sigma 300mm F2.8 APO EX DG HSM which has a weight of 2400g.
Filter Threads
The Tamron AF 70-300mm f4-5.6 LD has a filter size of 62mm 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 62mm filters that we recommend you to consider for the Tamron AF 70-300mm f4-5.6 LD:
And these are the 46mm filters that we recommend for the Sigma 300mm F2.8 APO EX DG HSM:
Lens Mounts
Both the Tamron AF 70-300mm f4-5.6 LD and the Sigma 300mm F2.8 APO EX DG HSM has the same Pentax KAF lens mount. Some of the latest released cameras that are compatible with the Pentax KAF lenses are Pentax K-3 III Mono, Pentax KF and Pentax K-3 III.
Tamron AF 70-300mm f4-5.6 LD is also available in the Canon EF , Nikon F (FX) and Sony Alpha mounts.
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
Tamron AF 70-300mm f4-5.6 LD 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.
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.
