The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 56mm F1.4 C and the Samyang 50mm F1.2 AS UMC CS 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. Samyang 50mm F1.2 AS UMC CS is the longer of the two lenses at 74mm. The Sigma 56mm F1.4 C with a length of 60mm, is 14mm shorter. Besides being longer, the Samyang 50mm F1.2 AS UMC CS also has a larger diameter of 68mm compared to the Sigma 56mm F1.4 C's 67mm 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 56mm F1.4 C weighs 280g, which means it is 95g (25%) lighter than the Samyang 50mm F1.2 AS UMC CS which has a weight of 375g.
Filter Threads
The Sigma 56mm F1.4 C has a filter size of 55mm whereas the Samyang 50mm F1.2 AS UMC CS 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 55mm filters that we recommend you to consider for the Sigma 56mm F1.4 C:
And these are the 62mm filters that we recommend for the Samyang 50mm F1.2 AS UMC CS:
Lens Mounts
Both the Sigma 56mm F1.4 C and the Samyang 50mm F1.2 AS UMC CS has the same Fujifilm X lens mount. Some of the latest released cameras that are compatible with the Fujifilm X lenses are Fujifilm X-S20, Fujifilm X-T5 and Fujifilm X-H2.
Sigma 56mm F1.4 C is also available in Nikon Z mount.
Samyang 50mm F1.2 AS UMC CS is also available in Canon EF-M , Micro Four Thirds and Sony E mounts.
Focal Range
Sigma 56mm F1.4 C is a prime lens with fixed focal lenght of 56mm which has an effective (full-frame 35mm equivalent) focal range of
84mm when used on a APS-C / DX format camera.
On the other hand, the Samyang 50mm F1.2 AS UMC CS is a prime lens with fixed focal lenght of 50mm which has an effective (full-frame 35mm equivalent) focal range of 75mm when used on a APS-C / DX format camera.