Photography is both an artistic and technical occupation. There are many variables in the process that a knowledgeable photographer can manipulate to produce a precise documentation or a work of fine art. If you wish to become a photographer first, you should know some basic knowledge of how to use cameras and can adjust focus, shutter speeds, aperture, lenses, and filters. You must know about the types and speeds of films. A good photographer will know about light and shadow, how to use available light and how to set up artificial lighting to achieve desired effects. To know about lens adjust is to learn about F-stop. Actually the term f-stop is a ratio. It has no dimensions. You cannot measure an f-stop in meters, inches, or degrees Fahrenheit. An f-stop is the ratio of two distances. It’s the ratio of the focal length of a lens to its diameter.
The letter ‘f’ came into use before the turn of the century in Germany, when the photographers divided the focal length of the lens by the diameter of the aperture to determine what is variously called the lens` light-gathering ability, speed or f-stop. For example, if the focal length of a lens is 4 inches and the diameter 2 inches, it would be an f: 2 lens. So that`s how the letter ‘f’ came into being, from the f-ocal length of the lens.
Take any object that you want to capture, if it is too bright to take a photo, you should close the f-stop. If the current f-stop setting is at 5.6, you should set the f-stop to 8. If the object you are taking is very dark, you may notice that there are an unusual number of void points in the range data. In this case, you should open the f-stop to allow more of the laser light to strike the CCD. If the current f-stop is set to 5.6, you should adjust it to 4 or 3.3.
Understanding f-stops are not hard once you get a bit of practice. Just remember that the lower the number, the bigger the opening and the higher the number, the smaller the opening. You also should know that each time you move from one stop to the next you double/half the amount of light passing through the aperture (is referred to the lens diaphragm opening inside a photographic lens). The technical aspect may be interesting to read once, but isn’t really necessary when taking pictures.