The focal length of a lens, represented in millimeters, is the distance from the point when the lights rays converge to the digital sensor, also known as the focal plane.
The focal length of a lens correlates to the angle of view, which tell us how much of the scene will be captured, and the magnification.
The longer the focal length, the narrower the angle of view and the higher the magnification. The shorter the focal length, the wider the angle of view and the lower the magnification.
For example, a 200mm lens is a telephoto lens, which means it is used to film objects far away. It has a narrow angle of view and a large magnification as it makes distance objects appear large. 200mm lenses are commonly used when filming events, or wildlife.
By contrast, an 18mm lens is a wide angle lens, which means it is used to film large spaces. It has a wide angle of view and a small magnification. 18mm lenses are commonly used when filming real estate as you need to capture the whole space in one image.
At Story Ninety-Four we have a wide range of focal length available to us from ultra-wide 10mm to super-telephoto 600mm. The focal length is another tool available to us a filmmakers to help us tell our story.