You asked
Is the sony fe 28mm f 2 good in low light?
Here is what the site says about that.
From Sony FE 28mm f/2: Sony FE 28mm f/2: A prime lens by Sony for Full frame cameras, 28mm f/2. Specs - Maker: Sony - Focal length: 28mm (prime) - Maximum aperture: f/2 - Made for: Full frame sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E): as marked, 28mm. - On APS-C (Sony E): like 42mm on full frame; f/2 gives about the depth of field ...
From Sony a6400: Sony a6400: A mirrorless camera by Sony with a 24.2-megapixel APS-C sensor, announced in 2019. Small and very quick to focus. There's no stabilisation in the body, so pick stabilised lenses for low light.
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