photographers

To gain optimum results and really good pictures, you need to make sure you are using your depth of field correctly. Depth of Field is a combination of two settings, the shutter speed and the aperture. A wide aperture, such as f/2.8 will give only the focal point perfect sharpness and clarity. the rest of the image will be blurry and unfocused, this is a very desirable effect, but it is not always what you want, generally wide apertures are used for macros or intentionally blurry artistic shots. Small apertures such as f/22 and f/16 are usually used for portraits, landscapes and anything other situation where you want the entire picture to be sharp and focused.
Because a wide aperture lets a lot of light through the lens, it will not take long to expose a film. A wide aperture should be combined with a fast shutter speed so the film is not over exposed. This works the other way too. A small aperture is only a pinhole big so lets very little light in. This means that the smaller the aperture the longer the shutter speed will need to be to expose a film correctly. this works all the way down, and depends on what the lighting is like where you are shooting.