The Exposure Triangle
The three elements that are a part of the Exposure Triangle are the shutter speed, aperture and ISO. The shutter speed at which the shutter is set relative to what the subject is. The faster the subject is moving the faster the shutter speed should be. Aperture refers to the mechanism that determines the volume of light that is allowed to hit the sensor. Aperture is the hole that allows light into the photo, so the bigger the aperture the smaller the size of the hole. ISO is the speed at which sensors collect light. The higher number the ISO is, the more artificial light is added to your image.
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How To Apply the Exposure Triangle to Taking a Photo
What makes a properly exposed image is a combination of the intensity of light and the time that light is allowed to expose the subject. A tool that shows if an image is properly exposed is called the light meter. Every DSLR includes a light meter that automatically measures the amount of light in the frame and determines the proper exposure. The light meter is a device that is used to measure the amount of light, and then calculate the shutter speed and aperture combinations for a given ISO that will produce a correct exposure. To avoid photos coming out to be over-exposed or under-exposed, aim to have the line resting on the center of the meter.
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