The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony E 15mm F1.4 G and the Samyang 12mm f2.0 for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is an important deciding factor when comparing two lenses. Sony E 15mm F1.4 G is the longer of the two lenses at 70mm. The Samyang 12mm f2.0 with a length of 59mm, is 11mm shorter. On the other hand, the Samyang 12mm f2.0 has a larger diameter of 73mm compared to the Sony E 15mm F1.4 G's 67mm diameter.
The weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Sony E 15mm F1.4 G weighs 219g, which means it is 41g (15%) lighter than the Samyang 12mm f2.0 which has a weight of 260g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Sony E Mount for size comparison purposes.
Wideangle Prime Lenses in Sony E Mount for Size Comparison
Lens Mounts
Both the Sony E 15mm F1.4 G and the Samyang 12mm f2.0 has the same Sony E lens mount. Some of the latest released cameras that are compatible with the Sony E lenses are Sony FX30, Sony ZV-E10 and Sony A6600.
Samyang 12mm f2.0 is also available in Canon EF-M , Fujifilm X, Micro Four Thirds and Samsung NX mounts.
Focal Range
Sony E 15mm F1.4 G is a prime lens with fixed focal lenght of 15mm which has an effective (full-frame 35mm equivalent) focal range of 22.5mm when used on a APS-C / DX format camera. Samyang 12mm f2.0 is a prime lens with fixed focal lenght of 12mm which has an effective (full-frame 35mm equivalent) focal range of 18mm when used on a APS-C / DX format camera.