The Sony FE 100-400mm lens is a full-frame, telephoto lens suitable for wildlife and sports photography. Although the lens has a shorter reach than the Sony FE 200-600mm lens , it is also lighter and more compact and boasts the GM tag which the 200-600 lacks, indicating better optical coatings and image quality. This lens is suitable for wildlife and big game but for birding, the 200-600mm is a much better option, simply based on the reach.
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