The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon RF 600mm F11 and the Sigma 20mm F1.8 EX DG RF 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 RF 600mm F11 is the longer of the two lenses at 270mm. The Sigma 20mm F1.8 EX DG RF with a length of 90mm, is 180mm shorter. Besides being longer, the Canon RF 600mm F11 also has a larger diameter of 93mm 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, 44% (410g) lighter than the Canon RF 600mm F11's weight of 930g.
Filter Threads
Both the Canon RF 600mm F11 and the Sigma 20mm F1.8 EX DG RF have the same Filter thread size of 82mm.
Below are links to the 82mm filters that we recommend you to consider for these lenses:
Lens Mounts
The Canon RF 600mm F11 has the Canon RF lens mount whereas the Sigma 20mm F1.8 EX DG RF has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Canon R6 V, Canon R6 III and Canon C50 for the Canon RF Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Sigma 20mm F1.8 EX DG RF is also available in Canon EF , Nikon F (DX), Sony Alpha and Sigma SA mounts.
Focal Range
Canon RF 600mm F11 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.
On the other hand, the 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.
