Is the canon rf 100 400mm f 5 6 8 is usm good for wildlife?

Yes, for a lot of wildlife, as long as you have good light. It's cheap, light, stabilised reach, but it gets dimmer as you zoom in, so it works best on sunny days and struggles at dusk or under tree cover.

On APS-C it frames like 160-640mm, which covers most backyard birds and larger animals. My wildlife and sport page suggests an APS-C body with a 100-400mm-class zoom as the best-value reach for starting out. From the cameras this lens fits, I'd look at:

• Canon EOS R7: APS-C, my pick for reach.
• Canon EOS R10: APS-C, a lighter, cheaper way in.
• Canon EOS R6 Mark II: full frame, if you want more room in low light.

Long lenses hold their value, so buying used can save a lot. See buying used.

Written by Claude from this site's pages.