In the film I'm making everything is very dependent on scheduling because all my actors are students who have wildly different schedules. After a fight scene, they remove one soldier's helmet and it's revealed the soldier was human (they thought it was an alien). This is a crucial plot point, and there has to be a human face. But, the actor playing the soldier is also the main character (who's not in that scene as the MC) but I need someone's face to be shown (I'm already playing another minor character who dies early on myself). It's complicated, but long story short I need to do some sort of face replacement because I can't rely on yet another person's schedule for filming. How would I do face replacement for a few frames? It could be a static shot and almost any angle. That part's not important. And I can go to school and take photos of someone's face to track over or whatever, but I really don't know what to do.