Is the panasonic lumix s 100 500mm f 5 7 1 ois long enough for birds?

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From Panasonic Lumix S 100-500mm f/5-7.1 OIS: Panasonic Lumix S 100-500mm f/5-7.1 OIS: A zoom lens by Panasonic for Full frame cameras, 100-500mm f/5-7.1. Panasonic's longest full-frame zoom, and it works with teleconverters. Specs - Maker: Panasonic - Focal length: 100-500mm (zoom) - Maximum aperture: f/5-7.1 (it gets darker as you zoom in) - Made for: Full frame sensors - Mounts: L-Mount - Stabilised: yes - Autofocus: yes What it frames like - On full frame (L-Mount): as marked, 100-500mm. - On APS-C ...

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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