Composition is what goes into, the placement of, and what is left out of the objects within the photo. With the auto exposure and the great exposure metering in today’s state-of-the-art cameras, together with the new fast auto focus lenses taking care of keeping the subject in focus, the most significant difference between a good photograph and a great photograph is often the composition. » More: Composition A-Z

As the photographer you are often able to control the quantity of light reaching the sensor by altering one or several of the four factors that affect the exposure. If each of the four factors only affected exposure, life would be simple; but changing the light, ISO, shutter speed, and aperture all have other consequences. » More: Controlling Exposure