Camera Basics

The camera is your basic tool when taking photographs and understanding their function can help you in taking better pictures. Whether a simple Point and Shoot, or a much more complicated SLR, there will be many functions on your camera. Understanding the many settings on the average digital camera can help you take the best photographs possible.

The foundation of still photography centres on the camera’s aperture. This includes how long it stays open and how big the hole gets. These two values, known as shutter speed and f-stop respectively, are primarily responsible for controlling light to the camera’s sensor. The longer the shutter speed, the more light that passes through the aperture to the camera’s sensor. Inversely, the bigger the f-stop, the smaller the aperture hole.

These values work in conjunction where a smaller hole in the lens requires a longer shutter speed. Think of it as filling a sink where you decide how fast the water comes out of the taps and how long you fill the sink. The taps are the f-stop where the bigger you open the valve, the more water that is captured, and the faster the sink fills. We relate the time you leave the taps running to your shutter speed, where the longer you leave the taps running, the more water that gets captured.

Both properties are inherent to the lens of the camera and with fixed-lens cameras such as point and shoot, you have little control over these settings, if any. However, with SLR lenses and cameras, you have finite control of these settings. Typically available lenses have f-stops ranging from f/2.8 to f/11. The typical cameras allow shutter speeds from mere milliseconds right up to seconds (1/125^th up to basically infinity).

These values can change independently, while your camera is in manual mode, but there are two more settings on the camera called aperture priority and shutter priority. When in aperture priority, the user sets the desired aperture value, and the camera determines the required, or best fit, shutter speed based on light levels. When the camera is in shutter priority, the user selects a desired shutter speed, and the camera will select the best f-stop.

Another camera setting related to light levels is ISO which is shortened from International Organization for Standardization, and refers to the camera’s sensitivity to light. The higher the value, the more sensitive the camera will be. Modern digital cameras have the advantage of setting an ISO value through the setting functions, whereas film cameras rely on selecting a film for a particular ISO. Some high-end professional digital cameras are capable of ISOs as high as 25,000.