The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 40mm F1.4 DG HSM A and the Sigma 50mm F1.4 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 40mm F1.4 DG HSM A is the longer of the two lenses at 157mm. The Sigma 50mm F1.4 EX DG HSM with a length of 68mm, is 89mm shorter. Besides being longer, the Sigma 40mm F1.4 DG HSM A also has a larger diameter of 88mm compared to the Sigma 50mm F1.4 EX DG HSM's 85mm 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 50mm F1.4 EX DG HSM weighs 505g, 59% (755g) lighter than the Sigma 40mm F1.4 DG HSM A's weight of 1260g.
Filter Threads
The Sigma 40mm F1.4 DG HSM A has a filter size of 82mm whereas the Sigma 50mm F1.4 EX DG HSM 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 82mm filters that we recommend you to consider for the Sigma 40mm F1.4 DG HSM A:
And these are the 77mm filters that we recommend for the Sigma 50mm F1.4 EX DG HSM:
Lens Mounts
The Sigma 40mm F1.4 DG HSM A has the Sony E lens mount whereas the Sigma 50mm F1.4 EX DG HSM has the Sony Alpha 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 Sony A99 II, Sony A68 and Sony A77 II for the Sony Alpha Mount.
Sigma 40mm F1.4 DG HSM A is also available in the Canon EF , Nikon F (FX), Sigma SA and Leica L mounts.
Sigma 50mm F1.4 EX DG HSM is also available in Canon EF , Pentax KAF3, Sigma SA, Nikon F (FX) and Four Thirds mounts.
Focal Range
Sigma 40mm F1.4 DG HSM A is a prime lens with fixed focal lenght of 40mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
60mm.
On the other hand, the Sigma 50mm F1.4 EX DG HSM is a prime lens with fixed focal lenght of 50mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 75mm.
