As the last major manufacturer, Sony is now finally providing a webcam solution for its cameras. However, the free software "Imaging Edge Webcam" is only available for Windows10 systems; it´s not known if a Mac version will follow. The tool will initially allow 35 Sony camera models to be used for live streams and video conferencing, including the recently introduced Alpha 7S III and many other Alpha models, the new ZV-1 as well as the RX0, RX10 (from version II) and RX100 (from version IV) -- see list of compatible models below.
Sony A7S III - now also usable as webcam
After installing the software, the camera is available for live streaming or video communication when connected to the PC via USB. However, the firmware of the cameras must also be updated beforehand. An image with a resolution of 1,024 × 576 is output and sound must be recorded via a separate microphone. For more detailed operating instructions, see 
this page.
Camera models compatible with Imaging Edge Webcam
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