1. What Hitchcock "touches" do you see in this early scene from the movie?
The cool angles & POV shots, such as the view of Cary Grant when he comes into the room and we see it from Ingrid Bergman's viewpoint, so that he is turned completely upside down as he talks to her. The POV closeups of Bergman's character as she wakes up & sees the glass before her & is told to drink up by Cary Grant. The use of shadows/light on Cary Grant, particularly, like when he is standing in shadow in the doorway.
2. How does Hitchcock choose to light, frame, and photograph his two stars in this scene?
As mentioned above, having Grant in dark shadow, framed in the doorway at first. The extreme closeup of Bergman early in the scene, giving us insight on how she feels at that moment - hungover, tired, groggy. We get several closeups to moderate closeups on each of them here. By the end of the scene, as she is confronted with her true feelings on the topic of patriotism and serving her country , they are finally standing closer together, the two of them rather framed together in the doorway.
What are some of the contrasts that Hitchcock is trying to set up between these two characters through art direction, costume, and cinematography?
His suit seems very neat, precise - and dark. So, while he seems to be one of "the good guys," there is still some mystery there and/or a strictly-business attitude that prevents us from really, fully knowing him at this point - is he really as good as he is supposed to be? Also, again, the mystery involved considering his very dark clothing. Her outfit, on the other hand, seems more "fun," sparkly, a mix of light & dark - oh, and it seems to be the outfit she was wearing the night before. So, not at all as put together as Cary Grant in the scene.
3. Based on this scene (or the entire film if you have seen it already), reflect on the casting of Cary Grant and Ingrid Bergman. Does this scene conform to or challenge their well-known star personas?
In this scene, I see a bit of both. There is conformity. For Cary Grant, he is working with the good guys against the bad Germans; he is suave, fashionable, trying to get a person who is "on the fence" to do the right thing & help her country. For Ingrid Bergman, despite the way her character seems, we learn she does love her country (U.S.) enough to refuse to help her father when he had tried to get her to work with some Germans against the U.S. Still, Bergman's character might also be something of a challenge, as she seems to initially be playing against the type we expect of her by apparently being a devil-may-care party girl whose father is a traitor. And, back to Grant, he also seems colder & more business-like than we often see from him.