Alongside the EOS R5 and R6, Canon has announced a brace of lenses, all in the short to long telephoto range. Filling out the ‘long’ end are one L-series zoom, and two innovative primes. Read further to learn more about the Canon RF 100-500mm F4-7.1L IS USM.

100-500mm F4-7.1L IS USM
Let’s start with the more conventional lens of the trio – the Canon RF 100-500mm F4-7.1L IS USM, which first appeared in mockup form at events earlier this year (remember when we had events?) featuring 20 elements in 14 groups, this is a complex design, which incorporates six UD (Ultra Low-Dispersion) elements and one ‘Super’ UD element. These elements should help control chromatic aberrations.
(Relatively) compact
The 100-500mm is relatively compact when zoomed ‘out’ to 100mm (207.6mm / 8.2 in) but extends (to 297mm / 11.7 in) at 500mm. A torque adjustment allows you to make the zoom movement stiffer or looser as desired, and lock the zoom ring if required.
Canon is at pains to reassure users that despite its telescoping design, this lens is very well-sealed against dust and moisture. At 1370 g (3 lbs), the 100-500mm is far from a lightweight lens, but it’s only a couple of hundred grams heavier than the much faster RF 70-200mm F2.8L IS USM. The front filter thread is a very reasonable 77mm.
A removable tripod collar allows the lens to be mounted directly onto a tripod, in situations where hand-holding isn’t desirable or practical.

Close focusing performance
Considering its focal length range, the 100-500mm offers good close focusing performance, with a minimum focus distance of 0.9m at the 100mm end of the zoom, and 1.2m at 500mm. This should make it practical for conventional short-tele portraiture. The maximum magnification ratio of 0.33X is achieved at 500mm (full extension at 500mm shown in this image).
Autofocus is handled by dual Nano USM motors that can work independently of one another for fast and silent AF.
5 stops of IS
This is a stabilized lens, rated at 5 stops of correction on an EOS R. When mounted on an R5 or R6, Canon claims that total stabilization with its I.S.-enabled lenses should improve due to both in-body and lens IS systems receiving information from the others’ sensors.
This two-way communication is enabled by the fast protocols developed for the RF mount. Canon quotes as much as an 8 stop benefit with some lenses. Canon claims you can expect 6 EV of correction from the 100-500mm and R5/6 combination, and this is something we’ll be sure to test as soon as we can. There are three IS modes to choose from: standard, panning or active during exposure.

Sample Images
Compatible with RF 1.4X and 2X teleconverters
The 100-500mm is compatible with Canon’s new RF 1.4X and 2X teleconverters, but only at focal lengths of 300mm and longer. A locking mechanism prevents their use at wider focal length positions, where damage might occur to the lens’ rear element.
The RF100-500mm F4.5-7.1 L IS USM lens is scheduled to be available in September 2020 for an estimated retail price of R54 999. The RF Extender 1.4x and 2x are scheduled to be available at the end of this month for an estimated retail price of R10 999 and R13 799.
Blog Credit to DPREVIEW (Barney Britton)