Exposure is a measurement of the amount of light hitting your camera’s sensor and determines how light or dark your picture looks. It can be controlled by shutter speed, aperture and ISO. Making adjustments to any of these not only affects your exposure but also the look of your photo.
Your camera can usually solve all your exposure needs using Auto modes. However, learning how the different elements affect your photos will give you the confidence to take manual control. The resulting images will then stand out from the rest.
This video explains how to use the aperture, shutter speed and ISO settings to get the right exposure and effect for your photo.
Aperture is the size of the hole in the lens through which light passes. Each lens has a range of aperture settings from large to small. Use Aperture Priority mode (Av) to control the aperture whilst still letting your camera look after overall exposure.
Aperture is measured as an f-number. Large apertures are expressed as small numbers, such as f/2.8, letting in more light and producing a shallow depth of field (increased blur beyond your point of focus). Small apertures are described by larger numbers, such as f/16, letting in less light and producing large areas in focus from foreground to background.