A typical camera set-up in lecture halls consists of four cameras: One long-shot (1), one lecturer (2), one for the slides (3) and one for the audience (4). Here a schematic view:

Here a real image of our test scenario (The cameras and streaming servers are marked with red circles):

Besides the director and the cameramen, additional parts are necessary or nice to have. In the next figure all necessary parts got a white background, all others a grey one.