If you're looking for a long telephoto lens for the mirrorless R system, Canon has some great options available. The RF 200-800mm f/6.3-9 IS USM is the most recent one, and I predict it will become a very popular lens. And it's with good reason. If you ignore the extremely expensive long telephoto prime lenses in the Canon R-series, there are three lenses to choose from. One of those is the beautiful and versatile RF 100-500mm f/4.5-7.1L IS USM, a lens that covers a large focal length range, making it useful for both landscape photography and wildlife photography.
Image One Camera and VideoCanon RF 200-800mm f/6.3-9 IS USM Lens (Canon RF)
Perfect for wildlife, sports, travel and more, the Canon RF 100-400mm f/5. 6-8 IS USM Lens is a compact, lightweight telephoto lens for EOS R Series cameras, offering a versatile zoom range that brings subjects closer with ease. The RF100-400mm F5. 6-8 IS USM is similar in size to the EF 70-300mm F4. 5-5.
Canon - RF 100-400mm f/5.6-8 Is USM Lens
RF200-800mm f/6.3-9 IS USM: Canon's First Telephoto Zoom to Reach 800mm
Canon RF 200-800mm f/6.3-9 IS USM review: the most…
Canon RF 200-800mm F/6.3-9 IS USM Lens Hands-On Review
Canon Announces $1900 RF 200-800mm F6.3-9 Super-Telephoto Lens
Wildlife photography with the RF 200-800mm F6.3-9 IS USM - Canon Middle East
Canon launches the first ever 800mm super-telephoto zoom lens
Canon RF 200-800mm F/6.3-9 IS USM Lens Hands-On Review
Canon RF 200-800mm F6.3-9 IS USM Review
Canon RF 200-800mm f/6.3-9 IS USM Lens - The Camera Exchange
Canon RF 200-800mm F6.3-9 IS USM Lens Review - Campkins Cameras