Introduction to Camera Modes: Aperture Priority Mode
You should know that something called aperture and another one called Shutter Speed are closely related. Whatever you do with one, you can’t do it without the other. Aperture is the opening size in the lens to let light come in. A bigger aperture lets more light come in, and a smaller aperture lets less light come in. Aperture is measured in f-numbers, so you will find measurements like f-5.6, f-11, f-22, etc. The smaller the number the bigger the aperture.
Don’t worry if this sounds too vague or general, your objective at this point is learning how to change the aperture number, not what you can do with it or what is it for. You will learn more about aperture and shutter speed and the cool things you can do with them in the section of exposure. For now keep in mind that in aperture mode you set the aperture to whatever number you want and the camera will figure out what the shutter speed should be.
Where is the aperture control? Besides the dial to change modes, most DSLR cameras have a second dial also on the right side of the camera, either on the front or the back, which can be used to increase or reduce the aperture. It can be a ring on the right top or a circular controller on the back. Be aware, however, that in some cases, especially with older lenses, you change the aperture using the lens itself by rotating an aperture ring. Moreover, some non-DSLR cameras (especially point-and-shoot cameras) may not even have a direct controller to change the aperture. In some of these cases, changing the aperture number may be possible by navigating through the menu displayed on the LCD screen.
It is essential you know 1) how to set your camera to aperture mode and 2) how to increase and decrease the aperture. If you can’t find a way to do it in your camera model, look for the manual and learn these two things.
IMAGE showing horizontal ring type or view from the top type of ring.
Exercise: Take your camera and 1) set your camera to Aperture priority mode. 2) Change the aperture mode to different numbers so you can see how the numbers change and make sure the flash is turned off. 3) Take a picture set at an aperture of f-22 and another picture at f-5.6. 4) Take more pictures at some other different aperture numbers of your own choice.
Note: You may notice that taking pictures at smaller apertures (the bigger numbers) you camera may take longer time to take a picture and your picture may end up blurry. This is normal when you have a slow shutter speed. There are ways to prevent this or ways to profit from such blurriness to produce wonderful pictures. You will learn more about it in the exposure section. For now if you get blurry pictures, don’t worry. The purpose now is learning how to set the camera modes. Taking wonderful shots comes afterwards.