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With a cropped sensor mirrorless camera from canon R series, if I have to choose between canon RF 100-400mm f/5.6-8 IS USM and canon RF 600mm f/11 IS STM as my first lense for bird photography, which lense should I choose and why so?
If I have to choose between canon EOS R 50 and Canon EOS R10 for bird photography, which camera should I choose and why so?