COMPOSITION
In cinematography, composition refers to the frame of the image and how the elements of the mise-en-scène appear in it. Composition guidelines must be observed when telling stories visually, as in filmmaking. Useful conventions are applied to make heroes stronger, villain ominous, generate anxiety and give the audience tranquility.
(Composition rules and conventions are older than cinema and photography. Most concepts have been used for thousands of years in painting. Filmmakers and photographers have borrowed many techniques from painters and used them as a springboard for new ideas and practices.)
RULE OF THIRDS
Another basic composition principle is called Rule of Thirds. To follow it, you must imagine the frame with two vertical lines and two horizontal lines, as to create three vertical sections of the same dimensions and three vertical sections also of the same size. The result is something like this:
The intersections of the lines are points of interest, where important objects are often placed. These points of interest are comfortable to the eye, thus the middle portion of the frame are kept "empty" or clear.
USE OF DIAGONAL LINES
Diagonal lines generally work well to draw the eye of an image’s viewer through the photograph. They create points of interest as they intersect with other lines and often give images depth by suggesting perspective They also can add a sense of action to an image and add a dynamic looks and feel as well as leading the eye to your photograph’s main subject or point of interest.
(I found this video below incredible useful in explaining the rule of thirds)
