The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 20mm F1.8 EX DG RF and the Canon 600mm f4.0L IS II USM 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. Canon 600mm f4.0L IS II USM is the longer of the two lenses at 449mm. The Sigma 20mm F1.8 EX DG RF with a length of 90mm, is 359mm shorter. Besides being longer, the Canon 600mm f4.0L IS II USM also has a larger diameter of 168mm compared to the Sigma 20mm F1.8 EX DG RF's 89mm 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. Sigma 20mm F1.8 EX DG RF weighs 520g, which means it is 3400g (86%) lighter than the Canon 600mm f4.0L IS II USM which has a weight of 3920g.
Filter Threads
The Sigma 20mm F1.8 EX DG RF has a filter size of 82mm whereas the Canon 600mm f4.0L IS II USM has a 52mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 82mm filters that we recommend you to consider for the Sigma 20mm F1.8 EX DG RF:
And these are the 52mm filters that we recommend for the Canon 600mm f4.0L IS II USM:
Lens Mounts
The Sigma 20mm F1.8 EX DG RF has the Pentax KAF lens mount whereas the Canon 600mm f4.0L IS II USM has the Canon EF lens mount. Some of the latest released cameras that are compatible with these mounts are Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount and Blackmagic URSA 12K LF, Z CAM E2-F6 II 6K and Z CAM E2-S6 II 6K for the Canon EF Mount.
Sigma 20mm F1.8 EX DG RF is also available in the Canon EF , Nikon F (DX), Sony Alpha and Sigma SA mounts.
Focal Range
Sigma 20mm F1.8 EX DG RF is a prime lens with fixed focal lenght of 20mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
30mm.
On the other hand, the Canon 600mm f4.0L IS II USM is a prime lens with fixed focal lenght of 600mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 960mm.
