A lens is an optical device made of curved glass that allows light to pass through it.
In order to reduce the size of the photo we need to bend the light to create an image that will fit onto a camera sensor. To adjust the focus the photographer can change the aperture on the camera in order to alter the amount of light entering the lens, this affects the depth of field of the object being seen. Depth of field also known as focus range is the distance between the nearest and the furthest objects giving a focused image. |