There are actors (such as Kenneth Branagh) who perform just as well on stage as they do on film. Nicole Kidman once said it's every actors' dream to do both after she did "The Blue Room". I've seen other actors who are hardcore classically trained but when they do movies, they don't blend very well. Since theater acting has its differences from film acting and seeing actors that are doing theater and film constantly, is it challenging or hard to switch back and forth? Thank you.