The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang 100mm F2.8 Macro and the Sigma 105mm F1.4 DG HSM for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Sigma 105mm F1.4 DG HSM is the longer of the two lenses at 132mm. The Samyang 100mm F2.8 Macro with a length of 123mm is 9mm shorter. Besides being longer, the Sigma 105mm F1.4 DG HSM also has a larger diameter of 116mm compared to Samyang 100mm F2.8 Macro's 73mm diameter.
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. Samyang 100mm F2.8 Macro weighs 720g, which means it is 925g (56%) lighter than the Sigma 105mm F1.4 DG HSM which has a weight of 1645g.
Lens Mounts
Both Samyang 100mm F2.8 Macro and Sigma 105mm F1.4 DG HSM has the same Sony E lens mount. Some of the latest released cameras that are compatible with the Sony E lenses are Sony A7R V, Sony FX30 and Sony A7 IV.
Samyang 100mm F2.8 Macro is also available in Canon EF , Fujifilm X, Micro Four Thirds, Nikon F (FX), Pentax KAF, Samsung NX and Sony Alpha mounts.
Sigma 105mm F1.4 DG HSM is also available in Canon EF , Nikon F (FX) and Sigma SA mounts.
Focal Range
Samyang 100mm F2.8 Macro is a prime lens with fixed focal lenght of 100mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides an 35mm (FF) equivalent of 150mm.
Sigma 105mm F1.4 DG HSM is a prime lens with fixed focal lenght of 105mm which has an effective (full-frame 35mm equivalent) focal range of 157.5mm when used on a 35mm FF format camera.