A question-and-answer session after the presentation also helps explain how Microsoft produces the holographic effect for an external camera at an event. While HoloLens normally maps environments in real-time, Microsoft pre-maps the stage so that it can maintain the demo even when the WiFi invariably bogs down. Also, while the outside camera uses a fisheye lens to create an extremely wide field of view, Kipman is quick to note that the points of light in a given area are identical -- the experience is fundamentally the same. In short, you'll probably feel like you got your money's worth if you dared to drop $3,000 on the developer HoloLens unit.