Magnified Portion of a Larger Image as a Frame?

Alright, I have a project I have to do and have made a large stage because it will be the only setting of the animation:

It is supposed to be a talkshow stage. I need to be able to zoom in to the desk and the chair in order to get a close-up of the people as they’re talking. Is it possible to simply zoom in the entire image itself or will I have to make a whole nother image?