Canon rf s 7 8mm f 4 stm dual vs canon 3 9mm f 3 5?

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From Canon RF-S 7.8mm f/4 STM Dual: Canon RF-S 7.8mm f/4 STM Dual: A prime lens by Canon for APS-C cameras, 7.8mm f/4. A twin lens for recording spatial video, made for the R7. Specs - Maker: Canon - Focal length: 7.8mm (prime) - Maximum aperture: f/4 - Made for: APS-C sensors - Mounts: Canon RF - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Canon) (Canon RF): like 12mm on full frame; f/4 gives about the depth of ...

From Canon RF-S 3.9mm f/3.5 STM Dual Fisheye: Canon RF-S 3.9mm f/3.5 STM Dual Fisheye: A prime lens by Canon for APS-C cameras, 3.9mm f/3.5. A twin-lens 3D VR lens for APS-C bodies, with autofocus.

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