What are the alternatives to the nikon z 600mm f 4 tc vr s?

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From Nikon Z 600mm f/4 TC VR S: Nikon Z 600mm f/4 TC VR S: A prime lens by Nikon for Full frame cameras, 600mm f/4. A pro wildlife lens with a built-in 1.4x teleconverter. Specs - Maker: Nikon - Focal length: 600mm (prime) - Maximum aperture: f/4 - Made for: Full frame sensors - Mounts: Nikon Z - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Nikon Z): as marked, 600mm. - On APS-C (Nikon Z): like 900mm on ...

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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