What is Focal Length?
Focal length, in simple terms, is the distance between the lens and the image sensor when the subject is in focus. Usually measured in millimeters (mm), it is an essential concept in photography and videography, determining how ‘zoomed in’ your photos or videos appear to be. The larger the focal length, the more zoomed your image will be.
Understanding Focal Length
Focal length affects not just how ‘zoomed in’ your image appears, but also how much of the scene your lens can capture. This is known as the field of view. A lens with a small focal length, say 18mm, will have a wide field of view, meaning it can capture more of the scene. A lens with a larger focal length, say 100mm, will have a narrow field of view, thus capturing less of the scene but in greater detail.
Focal Length and Perspective
Another critical aspect that focal length affects is perspective. Wide-angle lenses (small focal length) can exaggerate perspective, making objects appear further apart than they actually are. Telephoto lenses (large focal length), on the other hand, compress perspective, making objects appear closer together. This is why portrait photographers often use lenses with a focal length of around 85mm as it provides a flattering perspective and a good level of detail.
Types of Focal Length
- Wide Angle: Wide-angle lenses have a focal length of around 24mm to 35mm. They provide a broad field of view, making them ideal for landscape and architecture photography.
- Standard: Standard lenses have a focal length of around 35mm to 70mm. This is similar to the field of view of the human eye, making these lenses versatile and suitable for a wide range of uses.
- Telephoto: Telephoto lenses have a focal length of 70mm and above. They provide a narrow field of view and a high level of magnification, making them perfect for wildlife photography and sports photography.
Choosing the Right Focal Length
Choosing the right focal length depends on the type of video or photo you want to capture. For vast landscapes, a wide-angle lens would be suitable. For portraits, a lens with a focal length of around 85mm would be ideal. For wildlife or sports photography where you can’t get close to the subject, a telephoto lens would be the best choice.
Remember, understanding and mastering focal length can greatly improve your videography and photography skills, giving you better control over your shots and the stories you want to tell.