The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Venus Laowa 4mm F2.8 RF and the Rokinon 8mm f3.5 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. Rokinon 8mm f3.5 Fisheye is the longer of the two lenses at 77mm. The Venus Laowa 4mm F2.8 RF with a length of 26mm, is 51mm shorter. Besides being longer, the Rokinon 8mm f3.5 Fisheye also has a larger diameter of 75mm compared to the Venus Laowa 4mm F2.8 RF's 61mm 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. Venus Laowa 4mm F2.8 RF weighs 135g, which means it is 308g (69%) lighter than the Rokinon 8mm f3.5 Fisheye which has a weight of 443g.
Lens Mounts
The Venus Laowa 4mm F2.8 RF has the Canon RF lens mount whereas the Rokinon 8mm f3.5 Fisheye has the Canon EF lens mount. Some of the latest released cameras that are compatible with these mounts are RED Komodo-X 6K, RED Komodo 6K and Canon EOS C70 for the Canon RF Mount and Canon T8i, Canon 90D and Canon SL3 for the Canon EF Mount.
Rokinon 8mm f3.5 Fisheye is also available in Nikon F (FX) , Four Thirds, Pentax KAF, Sony Alpha and Samsung NX mounts.
Focal Range
Venus Laowa 4mm F2.8 RF is a prime lens with fixed focal lenght of 4mm which has an effective (full-frame 35mm equivalent) focal range of
6mm when used on a APS-C / DX format camera.
On the other hand, the Rokinon 8mm f3.5 Fisheye is a prime lens with fixed focal lenght of 8mm which has an effective (full-frame 35mm equivalent) focal range of 12.8mm when used on a APS-C / DX format camera.
