One of the ways you can change the mood of a scene is simply by changing the angle of the camera. In this post I have presented the same basic scene from 3 slightly different camera angles. I purposefully kept the camera on the same side of the character to help show how the change can effect the feeling of the scene. To begin with I have a level camera to the character. Here you get the feeling the lady is remembering something or someone. A scene like this often is accompanied by a camera move either in or out depending upon the point in the story that it appears. Next I have a low camera angle that give a more heroic or dramatic feeling.
With this type of camera angle give the character a sense of accomplishment. Either that they will be able to overcome or have already have triumphed. It's basically putting the character on a pedestal. It harkens back to the age of Kings and Queens standing on their balconies looking down upon the peasants. Of course this camera angle can be pushed to the point that a character appears taller than they are. Even old propaganda posters used images of people from low angles. Accompanied with harsh shadows can make it even feel sinister. Often you will see films in which a character that is in a desperate situation use low camera angles with harsh shadows.
The opposite of this is the downshot or high camera angle. It gives a sense of bewilderment or loss. That perhaps the character didn't get what they were after. Like the first example you will often find a shot like this accompanied with a camera move out. It can also be pushed to give a stronger feeling. A downshot also helps to give scale and place the characters into their world. In many live action movies a crane is used to bring the camera to this angle. No matter how you use these angles it's always good to keep in mind that the angle should not feel out of place. I find it is always best for you audience to not be so aware of the camera. This included camera moves.