You asked
Is the canon rf 10 20mm f 4l is stm worth it?
Here is what the site says about that.
From Canon RF 10-20mm f/4L IS STM: Canon RF 10-20mm f/4L IS STM: A zoom lens by Canon for Full frame cameras, 10-20mm f/4. Specs - Maker: Canon - Focal length: 10-20mm (zoom) - Maximum aperture: f/4 - Made for: Full frame sensors - Mounts: Canon RF - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Canon RF): as marked, 10-20mm. - On APS-C (Canon) (Canon RF): like 16-32mm on full frame; f/4 gives about the depth of ...
From Sensor sizes: Is full frame worth it?: For low light, events, and portraits with very shallow depth of field, yes. For travel, street, wildlife on a budget, and most hobby photography, a good APS-C camera with good lenses is enough, and you'll carry it more. Lenses and light matter more than the last stop of sensor performance.
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