RICHARD BUTLER, DPREVIEW:
The RX10 IV, as the name suggests, is the fourth in Sony's series of 1"-type sensor, long zoom compacts. The Mark IV is the first to offer phase detection autofocus alongside a series of changes designed to boost the speed and capability of the camera, for both stills and video shooting.
Sony is adamant that the camera is much more than an RX10 III with an RX100 V sensor in it. Let's take a look at what the latest version brings.
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