Is the sony a7r good in low light?

Here is what the site says about that.

From Sony a7R: Sony a7R: A mirrorless camera by Sony with a 36.4-megapixel full frame sensor, announced in 2013. Specs - Maker: Sony - Mount: Sony E - Sensor: Full frame, 36 x 24mm, crop factor 1.0 - Resolution: 36.4 megapixels - Stabilisation: none in the body; use stabilised lenses for slow shutter speeds - Announced: 2013 - Type: mirrorless camera Focal lengths on it Full frame is the reference size: lenses frame as marked. ...

From Sony a7S III: Sony a7S III: A mirrorless camera by Sony with a 12.1-megapixel full frame sensor, announced in 2020. Built for video and low light; 12 megapixels is little for stills.

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