The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony FE 50mm F1.4 GM and the Sigma 30mm F1.4 DC 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. Sony FE 50mm F1.4 GM is the longer of the two lenses at 96mm. The Sigma 30mm F1.4 DC HSM with a length of 63mm, is 33mm shorter. Besides being longer, the Sony FE 50mm F1.4 GM also has a larger diameter of 81mm compared to the Sigma 30mm F1.4 DC HSM'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. Sigma 30mm F1.4 DC HSM weighs 435g, 15% (81g) lighter than the Sony FE 50mm F1.4 GM's weight of 516g.
Filter Threads
The Sony FE 50mm F1.4 GM has a filter size of 67mm whereas the Sigma 30mm F1.4 DC HSM has a 62mm 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 Sony FE 50mm F1.4 GM:
And these are the 62mm filters that we recommend for the Sigma 30mm F1.4 DC HSM:
Lens Mounts
The Sony FE 50mm F1.4 GM has the Sony E lens mount whereas the Sigma 30mm F1.4 DC HSM has the Canon EF 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 Canon T8i, Canon 90D and Canon SL3 for the Canon EF Mount.
Sigma 30mm F1.4 DC HSM is also available in Nikon F (DX) and Sigma SA mounts.
Focal Range
Sony FE 50mm F1.4 GM 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.
On the other hand, the Sigma 30mm F1.4 DC HSM is a prime lens with fixed focal lenght of 30mm which has an effective (full-frame 35mm equivalent) focal range of 48mm when used on a APS-C / DX format camera.