Canon rf 16 28mm f 2 8 is stm vs canon 15 30mm f 4 5 6 3?

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From Canon RF 16-28mm f/2.8 IS STM: Canon RF 16-28mm f/2.8 IS STM: A zoom lens by Canon for Full frame cameras, 16-28mm f/2.8. A small non-L f/2.8 wide zoom, the partner of the RF 28-70mm f/2.8. Specs - Maker: Canon - Focal length: 16-28mm (zoom) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Canon RF - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Canon RF): as marked, 16-28mm. - On APS-C (Canon) ...

From Canon RF 15-30mm f/4.5-6.3 IS STM: Canon RF 15-30mm f/4.5-6.3 IS STM: A zoom lens by Canon for Full frame cameras, 15-30mm f/4.5-6.3.

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