Om system m zuiko 100 400mm f 5 6 3 is ii vs panasonic 100 400mm f 4 6 3?

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From OM System M.Zuiko 100-400mm f/5-6.3 IS II: OM System M.Zuiko 100-400mm f/5-6.3 IS II: A zoom lens by OM System for Micro Four Thirds cameras, 100-400mm f/5-6.3. Specs - Maker: OM System - Focal length: 100-400mm (zoom) - Maximum aperture: f/5-6.3 (it gets darker as you zoom in) - Made for: Micro Four Thirds sensors - Mounts: Micro Four Thirds - Stabilised: yes - Autofocus: yes What it frames like - On Micro Four Thirds (Micro Four Thirds): like 200-800mm on full frame; f/5-6.3 ...

From Wildlife and sport: Reach: Focal length is the first thing to sort out. - Sport from the sideline and larger animals: 70-200mm to 100-400mm on full frame. - Birds: 600mm full-frame equivalent and beyond. Birds are small and far away; a common saying is that you never have enough reach for them. Smaller sensors help here. A 100-400mm lens on APS-C gives the view of about 150-600mm on full frame, and on Micro Four ...

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