The method is unattended, in the sense that it's photos + camera parameters in and scene representation out. The photos should all be of the same scene (e.g. the Trevi Fountain). Once you have a scene representation, you can ask what the scene would look like from new camera angles with your choice of lighting.

Choosing camera angles is straightforward. You tell me where and what direction the camera is facing. The question then becomes, how do you specify your choice of lighting? The answer is, you can't do so directly. Instead, you provide a picture with the lighting you want, and with a little magic, we can find a way to imitate that lighting. The way we do is by finding a corresponding "appearance embedding" via numerical optimization.