Hi Joao, It all depends on what you mean by Talking Head. In technical term, the Talking Head is a tiny camera take of the speaker placed on a corner of the main content (usually lower right corner). If that is what you are referring to, then it doesn't matter, as long as is reasonably visible. Its function is not to show your face, but only to improve the connection between you and your public. It's a psychological improvement, but your students' real focus is always on the main content, never on the Talking Head. If on the other hand, you are referring to yourself as the main content, full screen or so, then things are quite different. In that case, you want to use a Chroma Key approach, draping a green or blue backdrop (depending on what you are wearing), then replacing that in post-production. A good standard replacement is a gradient or a blurred and desaturated panorama, so to enhance the speaker. Using Chroma Key when the speaker is the main content also helps to add callouts and other visual elements to improve communication.
... View more