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What are the alternatives to the canon ef 40mm f 2 8 stm?

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From Canon EF 40mm f/2.8 STM: Canon EF 40mm f/2.8 STM: A prime lens by Canon for Full frame cameras, 40mm f/2.8. Specs - Maker: Canon - Focal length: 40mm (prime) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 40mm. - On APS-C (Canon) (Canon EF): like 64mm on full frame; f/2.8 gives about the depth of ...

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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