When you look at your scene in Maya LT, you are looking through a camera. Think of it as being a director on a movie set and looking through a camera lens. Your field of view is restricted to what you can see through that lens.
By default, Maya LT has four cameras that let you view your scene in a panel: the perspective camera and the three orthographic cameras (side, top, front) that correspond to the default scene views. You look through these cameras (panels) as you model, animate, shade, and texture objects.
When baking preview images, you may want to create one or more custom perspective cameras rather than using these default cameras to frame your scene.
For more information on the kind of cameras you can create, see Maya LT camera types.