Camera Focal Length
Camera Focal Length
We hear it all of the time, but what exactly is camera focal length and why is it important that you understand your specific camera’s capabilities in order to capture that shot? Don’t worry if you don’t fully understand what camera focal length means, we’re going to run through its definition in this post and how to recognise camera focal length on your own device.
What Is Camera Focal Length? - Focal length is usually represented in millimeters (mm), is the basic description of a photographic lens. It is not a measurement of the actual length of a lens, but a calculation of an optical distance from the point where light rays converge to form a sharp image of an object to the digital sensor or 35mm film at the focal plane in the camera. The focal length of a lens is determined when the lens is focused at infinity.
The focal length tells us; the angle of view, how much of the scene will be captured (and the magnification), plus how large individual elements will be! Put it this way, 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. It sounds a little like a tongue twister at first, but it’s actually pretty simple. While reading these posts it’s actually even more useful to have your camera with you and play around with the settings on your camera to get a better understanding of the camera’s settings/ capabilities on your own device.
The Types of Lenses – Where camera focal length is concerned, there are two types of lenses at play. These lenses are known as prime and zoom lenses. Prime lenses have a fixed camera zoom focal length and zoom lenses have variable focal lengths. The advantage of the zoom lens is its versatility. They are ideal when you are photographing a variety of subjects such as landscapes and portraits, and you just want one lens for both situations (ideal for a wedding gig as the photographer, yeah, we know, there’s no need to thank us!). Using a zoom lens also reduces the number of times that you’ll need to change the lens which saves time and limits the possibility of getting dust in the camera's mirror box or on the sensor.
The main advantages of prime or fixed focal length lenses are their size and weight as well as their maximum aperture or f/stop. Prime lenses tend to be more compact and lightweight than zoom lenses, which of course makes them easier to carry about on the job. No one wants the be that person with three rucksacks larger than life on the job. I mean people will ask where the photographer is and you’ll be the pile of bags! It’s not a good look, nor is it practical.
Prime lenses also tend to have a larger maximum aperture (f/1.4 to f/2.8). This is an advantage when shooting in low light conditions as it will increase the possibility of hand holding the camera and freezing the subject without shake or blur caused by the longer exposures. Photographing images using prime lenses with large apertures also means you can get a shallow depth of field which is useful for portraiture where you might want a softer or blurred background. This is known as bokeh, which we have touched upon in a previous blog post.
Top Tips - Wide angle lenses are the popular choice for landscapes, interiors, large group photos and when working in confined situations. Standard lenses are popular as they are closest to the angle of view we humans see, so a standard lens is a great choice when your desired style of photography is to feel like the viewer is in the room within the image. Standard lenses are the popular choice for a wide range of photography including portraiture, nature and low light situations where the photographer cannot use a flash or is looking to capture the scene with available light.
Photo + editing credit: All images in this blog post edited by the team here at Weddit and photographed by Lukas Griffin. To get started with our wedding photo editing service, you can create an account here.