Sony a7 iii vs sony a9?

Here is what the site says about that.

From Sony a7 III: Sony a7 III: A mirrorless camera by Sony with a 24.2-megapixel full frame sensor, announced in 2018. The full-frame bargain of the used market: still a very capable camera. Specs - Maker: Sony - Mount: Sony E - Sensor: Full frame, 36 x 24mm, crop factor 1.0 - Resolution: 24.2 megapixels - Stabilisation: in the body - Announced: 2018 - Type: mirrorless camera Focal lengths on it Full frame is the reference size: ...

From Sony a9: Sony a9: A mirrorless camera by Sony with a 24.2-megapixel full frame sensor, announced in 2017. A stacked-sensor sports camera, now a used bargain for fast action. Specs - Maker: Sony - Mount: Sony E - Sensor: Full frame, 36 x 24mm, crop factor 1.0 - Resolution: 24.2 megapixels - Stabilisation: in the body - Announced: 2017 - Type: mirrorless camera Focal lengths on it Full frame is the reference size: lenses ...

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