The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang 20mm F1.8 and the Olympus ED 8mm F1.8 Fisheye 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 20mm F1.8 is the longer of the two lenses at 88mm. The Olympus ED 8mm F1.8 Fisheye with a length of 80mm, is 8mm shorter. Besides being longer, the Samyang 20mm F1.8 also has a larger diameter of 83mm compared to the Olympus ED 8mm F1.8 Fisheye's 62mm 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 ED 8mm F1.8 Fisheye weighs 314g, 36% (183g) lighter than the Samyang 20mm F1.8's weight of 497g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Micro Four Thirds Mount for size comparison purposes.
Ultra-Wideangle Lenses in Micro Four Thirds Mount for Size Comparison
Lens Mounts
Both the Samyang 20mm F1.8 and the Olympus ED 8mm F1.8 Fisheye 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-3 Astro, OM System OM-5 II and OM System OM-3.
Samyang 20mm F1.8 is also available in the Canon EF , Canon EF-M, Fujifilm X, Nikon F (FX), Pentax KAF, Samsung NX, Sony Alpha and Sony E mounts.
Focal Range
Samyang 20mm F1.8 is a prime lens with fixed focal lenght of 20mm.
On the other hand, the Olympus ED 8mm F1.8 Fisheye is a prime lens with fixed focal lenght of 8mm which has an effective (full-frame 35mm equivalent) focal range of 16mm when used on a FourThirds format camera.
