The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 20-40mm F2.8 VXD and the Sigma 28mm F1.4 DG HSM A 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 28mm F1.4 DG HSM A is the longer of the two lenses at 108mm. The Tamron 20-40mm F2.8 VXD with a length of 86mm, is 22mm shorter. Besides being longer, the Sigma 28mm F1.4 DG HSM A also has a larger diameter of 83mm compared to the Tamron 20-40mm F2.8 VXD'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. Tamron 20-40mm F2.8 VXD weighs 365g, which means it is 560g (60%) lighter than the Sigma 28mm F1.4 DG HSM A which has a weight of 925g.
Filter Threads
The Tamron 20-40mm F2.8 VXD has a filter size of 67mm whereas the Sigma 28mm F1.4 DG HSM A has a 77mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 67mm filters that we recommend you to consider for the Tamron 20-40mm F2.8 VXD:
And these are the 77mm filters that we recommend for the Sigma 28mm F1.4 DG HSM A:
Lens Mounts
Both the Tamron 20-40mm F2.8 VXD and the Sigma 28mm F1.4 DG HSM A has the same Sony E lens mount. Some of the latest released cameras that are compatible with the Sony E lenses are Sony FX5, Sony A7R VI and Sony A7 V.
Sigma 28mm F1.4 DG HSM A is also available in Canon EF , Nikon F (FX), Sigma SA and Leica L mounts.
Focal Range
Tamron 20-40mm F2.8 VXD has a focal range of 20-40mm 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
30 - 60mm.
On the other hand, the Sigma 28mm F1.4 DG HSM A is a prime lens with fixed focal lenght of 28mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 42mm.
