Sony a7 vs sony a7s?

Here is what the site says about that.

From Sony a7: Sony a7: A mirrorless camera by Sony with a 24.3-megapixel full frame sensor, announced in 2013. The first Sony full-frame mirrorless: no stabilisation, and slow autofocus by today's standards. Specs - Maker: Sony - Mount: Sony E - Sensor: Full frame, 36 x 24mm, crop factor 1.0 - Resolution: 24.3 megapixels - Stabilisation: none in the body; use stabilised lenses for slow shutter speeds - Announced: 2013 - Type: mirrorless camera Focal ...

From Sony a7S: Sony a7S: A mirrorless camera by Sony with a 12.2-megapixel full frame sensor, announced in 2014. Specs - Maker: Sony - Mount: Sony E - Sensor: Full frame, 36 x 24mm, crop factor 1.0 - Resolution: 12.2 megapixels - Stabilisation: none in the body; use stabilised lenses for slow shutter speeds - Announced: 2014 - Type: mirrorless camera Focal lengths on it Full frame is the reference size: lenses frame as marked. ...

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