The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Olympus 15mm F8.0 and the Samyang 12mm f2.0 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 12mm f2.0 is the longer of the two lenses at 59mm. The Olympus 15mm F8.0 with a length of 9mm, is 50mm shorter. Besides being longer, the Samyang 12mm f2.0 also has a larger diameter of 73mm compared to the Olympus 15mm F8.0's 56mm 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. Olympus 15mm F8.0 weighs 22g, which means it is 238g (91%) lighter than the Samyang 12mm f2.0 which has a weight of 260g.
Lens Mounts
Both the Olympus 15mm F8.0 and the Samyang 12mm f2.0 has the same Micro Four Thirds lens mount. Some of the latest released cameras that are compatible with the Micro Four Thirds lenses are OM System OM-1 II, Panasonic G9 II and OM System OM-5.
Samyang 12mm f2.0 is also available in Canon EF-M , Fujifilm X, Sony E and Samsung NX mounts.
Focal Range
Olympus 15mm F8.0 is a prime lens with fixed focal lenght of 15mm which has an effective (full-frame 35mm equivalent) focal range of
30mm when used on a FourThirds format camera.
On the other hand, the 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.