這隻畫質還好CANON本身的100-400L我覺得應該是變焦長砲中算最滿意的sigma變焦比較優的是120-300mm f2.8這隻超棒但是太貴可以考慮sigma 100-300mm f4 EX APO DG 這隻sigma 120-300mm f2.8 vs 100-400Lhttp://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=381&Camera=9&Sample=0&FLI=2&API=3&LensComp=113&CameraComp=9&SampleComp=0&FLIComp=3&APIComp=0100-400L at 400mm