Sony a7r iii vs sony a7r iv?

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From Sony a7R III: Sony a7R III: A mirrorless camera by Sony with a 42.4-megapixel full frame sensor, announced in 2017. Also sold from 2021 as the a7R IIIA, with a sharper rear screen. Specs - Maker: Sony - Mount: Sony E - Sensor: Full frame, 36 x 24mm, crop factor 1.0 - Resolution: 42.4 megapixels - Stabilisation: in the body - Announced: 2017 - Type: mirrorless camera Focal lengths on it Full frame is the reference ...

From Sony a7R IV: Sony a7R IV: A mirrorless camera by Sony with a 61-megapixel full frame sensor, announced in 2019. Also sold from 2021 as the a7R IVA, with a sharper rear screen. Specs - Maker: Sony - Mount: Sony E - Sensor: Full frame, 36 x 24mm, crop factor 1.0 - Resolution: 61 megapixels - Stabilisation: in the body - Announced: 2019 - Type: mirrorless camera Focal lengths on it Full frame is the reference ...

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