Understanding the Exposure Triangle
We’ve come a long way from using film based cameras to digital ones. Technology has completely revolutionized the way we click pictures today. However, no matter how much technology evolves or changes the way we shoot images, there are some basic rules that will always have to be followed. Following these basic rules is what separates an amateur photographer from a professional one. Your camera has very little to do with how good a photographer you are.
One of the basic concepts of photography that will never change is the ‘Exposure Triangle’. The Exposure Triangle includes shutter speed, ISO, and aperture. Knowing these 3 basic elements of photography is key to becoming an expert photographer. Read on to known more.
The shutter speed refers to how long the camera’s shutter is open, which also determines the duration of light entering your camera. Typically, a DSLR camera possesses fast shutter speeds ranging between 1/4000th of a second to 1/8000th of a second. As for slower shutter speeds, the lowest in a typical DSLR would be around 30 seconds. This slow shutter speed is also referred to as a Bulb or B setting. The B setting allows the photographer to choose how long the shutter needs to be open. So, the higher the shutter speed, the lesser the duration of light entering the camera and vice versa.
Different shutter speeds have different purposes in photography.
- A shutter speed in the range of 1 to 30 or more seconds is generally used in low-light photography or night photography. Tripods are generally used with these shutter speeds to reduce camera shake.
- A 2 to ½ second shutter speed helps in creating a fantasy-like or other worldly atmosphere in images. This setting is generally preferred for landscape or nature photography.
- 1/60 to 1/100 shutter speed setting helps with hand-held photography without the assistance of a telephoto lens.
- 1/250 to 1/500 shutter speed setting helps with fast action shots or hand held photography with the help of a telephoto lens. Is especially used in sports photography.
- 1/1000 to 1/4000 is an extremely fast shutter speed and is used in high speed photography. You can use this to capture images of fast moving objects or for close-up shots.
ISO is basically short for International Standards Organization and refers to the film speed in old film based cameras. It is also used in reference to a camera’s sensitivity towards incoming light. Generally, the lower your ISO setting, the more light you will need to create better exposure. A lower ISO setting also helps reduce image noise or grains. Higher ISOs increase image noise and are generally used for dark or low-light environments.
The aperture has 2 main functions: controlling the depth of field and controlling the amount of light that passes thorough the lens. Depth of field refers to the distance between objects in the image. A small depth of field shows the foreground to be sharper than the background, while in a large depth of field, both the foreground and background appear sharp. A large depth of field (example: f22) is used for landscape shots, while a small depth of field (example: f4) can be used for portraits where the subject is isolated from the background.
Similarly, aperture settings also control the amount of light that enters your camera. However, here a lower f number denotes a larger aperture. For example, f4 would be a large aperture that allows more light to enter, compared to an f22 setting.
Balancing the Exposure Triangle
The Exposure Triangle is called so, because of how one setting can affect the other two. For Instance, changing the aperture can force you to change the shutter speed and the ISO. A landscape shot would require a large aperture for more depth of field, which would prevent too much light from entering the camera and hence, would require you to lower your shutter speed to make up for this loss of light. The trick is to manage the different Exposure Triangle settings to create perfect pictures.