How important is lighting in the film play?

Much of the impression movies leave on viewers stems from how lighting affects perception. It sets a particular mood. Bright, colorful lighting often brings with it cheerfulness in films. Actors seem happier. Dark colors suggest sinister characteristics in actors and set the mood for dark plots. So consider the scenes at the Tallis' countryside home are a haven of sorts, and the clean light brings to mind a feeling of innocence and purity. War, of course, uses lighting in different ways depending on character and specific scene. When Robbie sees the dead children in the forrest his face changes for an instant. At first drained and austere, the light suddenly warms for a moment (reminiscent of those earlier scenes) and then fades. It's brief, but it's a magnificent use of light. THere really is so much more to this question that I can't do it justice in this space. Please go to my source links below. Much of what I said is taken from them but there is much more detail to be had. Good Luck!