Adjusting the focal length on a camera is simple.
In photography, one factor that is arguably among the most important in terms of how your image will turn out is the focal length of your lens. This is the extent to which it magnifies the object on which you are focusing. If you have a long focal length, for example, your object will appear larger. A short focal length will cause it to seem smaller. Modern digital technology makes adjusting your camera's focal length a simple process.
Instructions
1. Power your camera on and access the main shooting screen. If you see images you have previously taken on the screen, press the "Playback" button, a circle with a rightward-pointing triangle inside of it, to exit from the playback menu and get to the shooting screen.
2. Check your camera's f-stop number and take a test shot. Your camera's f-stop number, denoted by the letter "f" followed by a slash and then a number (for example f/5.6), is inversely related to its focal length. In other words, as it increases, the focal length decreases. Take a test shot of an object at your initial focal length.
3. Turn your camera's "Function" dial, which is located near the shutter button, to adjust this number. Depending on the model of your camera, you may also need to press another button at the same time.
4. Take a second test shot at your new focal length and compare the two. In addition to differences in which objects (or, if your shot is at close range, which parts of the object) are in focus, you will notice differences in the amount of light present. This is because light has to travel a shorter distance to penetrate shots with low focal lengths---or, high f-stop numbers---than for high focal length. Without any other adjustments, the former type of shot will usually be brighter than the latter.
Tags: focal length, test shot, your camera, camera f-stop, camera f-stop number