As with any hobby, photography has an extensive vocabulary of technical terms, slang and techniques
This can create a feeling of uneasiness among beginners, as this vocabulary requires a second learning curve that exists on top of learning how to actually use a camera.
Photography lingo is a wall that beginners will run into immediately, as cameras on the market are labeled with a variety of specs that can seem like gibberish to a layman.
One such term is focal length.
Whether you want to enter the marketplace as an educated consumer or impress your friends, we have done you the favor of assembling 5 things you need to know about focal length.
It’s not nearly as complicated as it sounds.
Even though the information about focal length isn’t complicated, there are many different facets to its functionality.
Having a basic understanding of all of them will take you far in both buying a camera and using it in a knowledgeable fashion.
Sure, you can get by not knowing the many functions of your camera, but you won’t be using it to its fullest capacity.
To make sure you’re unlocking your camera’s maximum potential, here are 5 things you need to know about focal length.
1. What Does Focal Length Refer To?
This is, perhaps, the most obvious question surrounding the mystery wrapped up in an enigma that is focal length.
Let’s sound it out.
Focal sounds a lot like focus. This isn’t an accident, as focal length refers to the amount of distance that a camera can narrow in on a subject, without sacrificing image quality. Naturally, a longer focal length results in higher magnification capabilities, but a narrower viewpoint.
For instance, a lens with a 24mm focal length is going to give you a more comprehensive image. A lens with a 300mm focal length will give you a more focused, specific image.
If you want to get technical about it, focal length actually refers not to the length between your lens and the object your capturing. It’s actually referring to the distance between the lens and the light sensor in your camera, hence the usage of millimeters.
2. How Do You Know Which Focal
Length To Use?
Because a smaller focal length results in a more comprehensive picture, it’s best suited to things like landscapes, group photographs and pictures of large objects. Think of it as being more concerned with capturing a mountain range than the mountain goat in the foreground.
If you were to try to use a lens with a 300mm focal length to capture a group photo, you could very well end up with a picture of a single individual, or maybe even the eyeball of a single individual, depending on how close you are.
Due to the narrow field of vision, a lens with a large focal length is best suited to taking photos of flowers, specific objects in the istance or portraits. The frame becomes smaller and easier to fill, allowing the image to intensely focus on a single object.
In other words, if you’re looking to focus in on a single subject, a large focal length will come in handy. A small focal length, on the other hand, will be needed for photos with multiple subjects.
Of course, the more creative among you may find alternative means for both lenses, but these examples represent their basic purposes. Photography is an art, after all, so feel free to break the rules every once in a while.
3. How Does Focal Length Relate To Lenses?
Focal length is entirely determined by the lens you are using – it has nothing to do with the camera itself. Lenses can come in two different types, each of which has a different relationship with focal length.
The most common type of lens is the zoom lens, which allows the focal length to change on demand, depending on the situation you find yourself in. This is great for photographers who don’t quite know what to expect, but are reacting to the moment.
On the downside, zoom lenses are bigger and heavier, which can make for some awkward positioning. They’re also a bigger pain to carry around, as they’re going to take up much more room in your bag or purse, the space in which is already highly desirable real estate.
The other type of lens is called a prime lens. This lens has no zoom capabilities, but is, instead, fixed at a specific focal length. What it lacks in customizability, it makes up for with its compact design, which is much smaller than a zoom lens.
Prime lenses also have better aperture, meaning they can capture light better. This is particularly useful in low-light situations, such as capturing shadows from a street lamp or any other kind of night-time photography.
All in all, it’s best to have both a prime and zoom lens, as each is suited to a specific situation that you may find yourself in. Neither is the full package.
4. What Is The Relationship Between
Focal Length And Perception?
Maybe you’ve seen images of tourists holding up the Leaning Tower of Pisa or people who look like they have a third arm, due to someone standing behind at a particular angle. This is all a result of perception distortion, which goes hand-in-hand with focal
By setting the focal length just right and marrying it with the right angle, you can create some interesting optical illusions. Most famously, the actors who played hobbits in the “Lord of the Rings” films were made to appear short by using focal length and clever angling, not by using digital effects.
Outside of creating fun images, altering perception can result in striking images. For instance, laying on your back and using a small focal length on a tree, you can end up with an image that looks otherworldly. And that’s just with something as simple as a tree.
Using focal length to play with perception can result in all kinds of possibilities.
5. How Is Focal Length Affected By Digital Zoom?
We already know that zoom lenses can change focal length on the spot, thanks to their organic method of altering the lens. However, there’s also digital zooming, which
you’ll see on digital cameras and most smartphones.
While both are called zooming, digital zooming does not change the focal length. Instead, it simply crops out the edges of the image and magnifies the area you’re zooming toward. Because the focal length is never changed, the magnified image is blurry and features a major resolution downgrade.
This shows you how important focal length is for a great camera. Even though cameras on the modern smartphones can be extremely impressive, especially compared with the cell phone cameras of the past, their lack of such fundamental feature, such as focal length, puts them at a major disadvantage.
Focal Length: Easy To Understand,
Difficult To Master
On the outside, focal length sounds like a dense concept – something you quickly convince yourself impossible to understand.
But if you take the time to zoom in on focal length, you quickly realize that it’s not so difficult to understand It’s merely referencing the amount of space that an image can consist of. A small focal length results in a broad, comprehensive image, such as a skyline shot or a group photo. A large focal length results in a narrow, precise image, perfect for micro-photography and portraits.
It’s also important to know that certain lenses offer unique focal length capabilities, such as prime and zoom lenses. Prime lenses will fix the focal length to a specific setting, while zoom lenses allow for on-the-spot customization.
When you start to get into the more advanced photography arenas, such as perception, focal length can be an incredibly effective tool. You can use it to create fun images with
your friends or to create fascinating perspective shots for the purposes of art.
Whatever your reason for using focal length, it’s an all-purpose tool in the utility belt of the photographer.