I have just bought a Logitech C920 Pro HD Webcam to use on a Mac OS X version 10.11.6. It looks great live, but whenever I try to record a video, the quality is no better than that made with Photo Booth. I would like know what to do - which compatibl

Unfortunately the quality of the video is limited by the settings during capture and the camera's built-in resolution.

Higher end cameras offer sharper resolutions. If it says 1080p, it will look grainy on any Retina or better display.

You can reduce the frame rate to offer better resolution in some cases. You are best off trying to find a camera that matches your own screen resolution in capture capability.