The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 17-40mm f1.8 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 17-40mm f1.8 is the longer of the two lenses at 116mm. The Sigma 50mm F1.4 EX DG HSM with a length of 68mm, is 48mm shorter. On the other hand, the Sigma 50mm F1.4 EX DG HSM has a larger diameter of 85mm compared to the Sigma 17-40mm f1.8's 73mm 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, 5% (30g) lighter than the Sigma 17-40mm f1.8's weight of 535g.
Filter Threads
The Sigma 17-40mm f1.8 has a filter size of 67mm 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 67mm filters that we recommend you to consider for the Sigma 17-40mm f1.8:
And these are the 77mm filters that we recommend for the Sigma 50mm F1.4 EX DG HSM:
Lens Mounts
The Sigma 17-40mm f1.8 has the Sony E lens mount whereas the Sigma 50mm F1.4 EX DG HSM has the Canon EF lens mount. Some of the latest released cameras that are compatible with these mounts are Sony ZV-E10 II, Sony A6700 and Sony FX30 for the Sony E Mount and Blackmagic URSA 12K LF, Z CAM E2-F6 II 6K and Z CAM E2-S6 II 6K for the Canon EF Mount.
Sigma 17-40mm f1.8 is also available in the Leica L , Fujifilm X and Canon RF mounts.
Sigma 50mm F1.4 EX DG HSM is also available in Pentax KAF3 , Sony Alpha, Sigma SA, Nikon F (FX) and Four Thirds mounts.
Focal Range
Sigma 17-40mm f1.8 has a focal range of 17-40mm and
2.4X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
25.5-60mm when used on a APS-C / DX format camera.
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 1.6x crop, it provides a 35mm (FF) equivalent of 80mm.
