Beginner photographer may think that shooting in the creative modes is something difficult, unapproachable for a man of mould, but it is not so. Once you get into these modes, their use for you will be no more difficult than shooting in a fully automatic mode. It does not matter, in what mode you are shooting; the exposure (brightness) of photos is determined by three parameters: the exposure, diaphragm and sensitivity. When shooting in an automatic mode the camera will expose these options to obtain the standard exposure. At the same time, the camera measures the light of the scene, in other words, this device &;knows&; what amount of the incident light is there, and, basing on this knowledge, it expose the desired values of sensibility (ISO), diaphragm and exposure. All what you need is to direct the camera on the subject and press the shutter button.
At the same time for the graphic picture you need to control the depth resolution of shot, which is set by the diaphragm, fuzzy movements, which are determined by the exposure, and noise-emission level, which depends on the sensitivity of matrix.