Canon rf s 14 30mm f 4 6 3 is stm pz vs sigma 17 40mm f 1 8?

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From Canon RF-S 14-30mm f/4-6.3 IS STM PZ: Canon RF-S 14-30mm f/4-6.3 IS STM PZ: A zoom lens by Canon for APS-C cameras, 14-30mm f/4-6.3. A power-zoom kit lens for vlogging, sold with the R50 V. Specs - Maker: Canon - Focal length: 14-30mm (zoom) - Maximum aperture: f/4-6.3 (it gets darker as you zoom in) - Made for: APS-C sensors - Mounts: Canon RF - Stabilised: yes - Autofocus: yes What it frames like - On APS-C (Canon) (Canon RF): like 22-48mm on full ...

From Focal length converter: Aperture and depth of field: The f-number sets exposure, and that doesn't change with sensor size: f/2.8 gives the same brightness on a phone as on medium format. Depth of field does change. At the same framing, multiply the f-number by the crop factor to get the full-frame aperture with the same depth of field: f/1.8 on APS-C gives about the background blur of f/2.7 on full frame, and f/1.8 on Micro Four Thirds about ...

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