A Cinematographer is the person who has expertise in the art of capturing images either electronically or on film using visual recording devices. You will be responsible for the camera. You will zoom in or zoom out, mount the camera on a crane on a helicopter depending on the scene. You will compose how a certain frame is to be shot.
You will also be responsible for the way an actor or an actress looks on screen. You will decide the angles that make them look their best. This does not mean that you are just restricted to the camera. Cinematographers set the tone of a movie. Lighting plays an important part. You will select and arrange the lights. Warm or cool colors will affect our emotions, while the setting will affect our acceptance of the plot. The originality of the camera techniques used by the cinematographers ties every element together and directly affects the feel of the movie.
In a way, a cinematographer is like the umpire. After watching the game, you realize you haven't even noticed their presence. Their job is to support the game, to make it greater without the viewer noticing it.
Essentials to be an excellent Cinematographer:
An interest in photography including composition, lighting, movement and fine arts like music, painting, and even sculpture. A strong visual sense, good hand-eye coordination and ability to work with tools.
One of the most important quality for a cinematographer is the ability to visualise the whole story. Often an entire movie is shot over a long period in short snippets and at the end of the project, the whole movie has to blend in. You will be the one who has all this in your head at all times.
For this you need to be seeing, analyzing and discussing films, reading books on film craft, and observing film and video productions. Attending professional exhibitions, seminars and workshops also helps.
At an institute, you will learn techniques of shooting by candlelight, morphing, shooting in confined spaces, stretching daylight, using practical light, etc. Besides this you will learn about international cinema and get a bigger picture of filmmaking. Alternatively you can start as an assistant to an established cameraman. You can get to learn a lot of the practical aspects of cinematography. But there are strong chances that you might end up being just a good assistant!