When it comes to video production, the focal length of your lens plays a crucial role in shaping the look and feel of your footage.
Whether you’re filming a sweeping landscape, a close-up portrait, or an action shot, understanding how focal length affects your video will help you make better decisions about what lens to use.
In this post, we will explore how different focal lengths impact your field of view (FOV), scene compression, and the shots they best suit.
By the end, you’ll understand how to use focal lengths to enhance your storytelling and create more dynamic, professional-looking content.
What is Focal Length, and How Does It Impact Video?
Focal length is the distance between the lens and the camera sensor when the subject is focused. To dive deeper into focal lengths and how they impact smartphone video, see this guide on smartphone camera focal lengths.
This measurement is usually given in millimeters (mm) and determines two important aspects of your video: the field of view (FOV) and scene compression.
- Field of View (FOV): The amount of the scene visible in the shot. A shorter focal length (wide lens) captures a broader scene, while a longer focal length (telephoto lens) zooms in on a smaller portion.
- Scene Compression: How the space between objects in the shot is perceived. Shorter focal lengths keep objects in the frame spaced apart, while longer focal lengths compress the scene, making objects appear closer together.
Now, let’s discuss how different focal lengths affect these two factors.
1. Field of View (FOV): Shorter vs. Longer Focal Lengths
The field of view (FOV) is the area visible in your shot. It’s like the camera’s “window” to the world, and its size depends on your chosen focal length.
Shorter Focal Lengths (10mm – 24mm): Wide Field of View
Short focal lengths provide a wide field of view, capturing more of the scene. This makes them ideal for shots where you want to show a lot of context, like landscapes, architectural shots, or group scenes.
A wide FOV allows you to include more elements in the frame, making it perfect for scenes that need to feel expansive.
For example, a smartphone with an ultra-wide lens (13mm) can capture an entire room, landscape, or wide vista.
This wide view can make a small space more extensive and immersive. Ultra-wide lenses often exaggerate the distance between subjects, making them ideal for dramatic landscape shots or capturing large groups of people.
Longer Focal Lengths (50mm and above): Narrow Field of View
On the other hand, longer focal lengths result in a narrower field of view. These lenses focus on a smaller portion of the scene, zooming in on subjects and excluding much of the surrounding area.
This makes telephoto lenses great for isolating subjects and creating a more intimate, focused shot.
For instance, a smartphone’s 77mm telephoto lens allows you to zoom in on a subject, compressing the background and bringing distant objects closer.
This narrow FOV works well for portrait shots or capturing distant subjects like wildlife or athletes in action.
2. Scene Compression: How Focal Length Affects Depth Perception
Scene compression refers to how the space between objects in the frame appears relative to one another. Focal length plays a big role in this aspect of filming, influencing how “close” or “far” objects appear.
Shorter Focal Lengths: Minimal Compression
There is minimal compression with short focal lengths, like 10mm to 24mm. This means objects in the scene appear farther apart, giving a sense of depth.
For example, using an ultra-wide lens may make the foreground subject seem distant from the background, enhancing the sense of space and making the scene more open.
A great practical example is when filming landscapes: the ultra-wide lens captures vast expanses, making everything from mountains to trees appear spread out. The scene looks expansive, and you can see much of the environment in one frame.
Longer Focal Lengths: High Compression
With longer focal lengths, such as 77mm or beyond, the scene compression increases, meaning the apparent distance between the subject and the background decreases.
This can be used creatively to make distant objects seem closer together. The closer you zoom in on your subject, the more the background seems to come forward, flattening the scene’s depth.
For instance, using a 77 mm telephoto lens can produce a shot of a subject in the foreground, but the background might look compressed and closer than it is.
This is great for focusing on details and eliminating distractions, making the subject stand out more clearly.
3. Practical Examples of Different Focal Lengths
Now that we understand how focal length affects FOV and scene compression let’s examine practical examples and see how these concepts play out with different lenses.
Ultra-Wide Lens (13mm)
An ultra-wide lens is perfect for capturing expansive scenes or making small spaces appear larger. It exaggerates the distance between subjects and objects, creating a dramatic sense of space.
When shooting a landscape, the ultra-wide lens allows you to capture the full scope of the scenery, making vast vistas appear even more breathtaking.
Ultra-wide lenses also work great for filming in tight spaces. For instance, shooting an interior room with an ultra-wide lens can make a small apartment or office look much bigger.
If you’re filming a crowded event, like a concert or street scene, the wide FOV will allow you to capture the energy and the crowd all in one frame.
Standard Wide Lens (26mm)
A standard wide lens, like the 26mm equivalent on many smartphones, offers a balanced perspective. It’s neither too broad nor tight, making it the most versatile lens for general use.
This lens provides a more natural view of the scene, similar to how the human eye perceives it, and is excellent for most everyday filming needs, like talking head videos or vlogging.
It’s also an excellent option for capturing group shots or street photography, where you want a bit of context around your subject without distorting the scene too much.
A standard wide lens maintains the balance between the subject and the background, and the image feels natural.
Telephoto Lens (77mm)
A telephoto lens is ideal for zooming in on a subject while compressing the background. f you’re looking for smartphones with the best telephoto lenses, check out this list of the best smartphone brands for video content creation.
This lens is excellent for portraiture, wildlife photography, and sports filming, where you must isolate your subjects and bring them into sharp focus.
In a portrait shot, a telephoto lens helps blur the background, making the subject stand out. The compression effect makes your subject look more prominent while making the background seem closer, which is perfect for emphasizing a single subject and removing distractions.
Telephoto lenses are also great for capturing distant subjects, like wildlife or sports players on a field. The compression effect helps make the scene more cohesive, with everything appearing closer together, even though the subject may be far away.
4. Choosing the Right Focal Length for Your Shot
Understanding how focal length impacts your video will help you choose the right lens for any given shot. Here are a few quick tips for choosing the best focal length:
If you’re unsure how to switch between your smartphone’s built-in lenses for different focal lengths, check out this guide on switching smartphone lenses.
- Wide-Angle Lenses (13mm—26 mm): Use these for expansive shots, landscapes, and establishing shots. They’re great for capturing large scenes and making spaces look larger than life.
- Telephoto Lenses (50mm—77 mm): These lenses isolate subjects, compress the background, and capture distant action. They’re great for portrait shots and wildlife filming.
Conclusion
Focal length is a powerful tool in your smartphone videography arsenal. Whether using a wide-angle lens to capture sweeping landscapes, a standard lens for balanced shots, or a telephoto lens to zoom in on distant subjects, understanding how focal length affects your video can elevate your content and storytelling.
Experimenting with different focal lengths will help you capture various shots and create more dynamic, engaging videos.
By mastering how field of view and scene compression influence your shots, you’ll be able to create content that feels more polished, professional, and visually captivating.
So, next time you’re filming, think about the lens you’re using and how it shapes the story you want to tell!