How can you find your Lens Focal Length?
When you look at your camera lenses, you see many different numbers. These numbers can be very confusing when you just started photography. This article will talk about the Lens Focal Length and the other uses of various Focal Length.
What is Lens Focal Length?
The Lens Focal Length is in millimetre (e.g. 35mm, 50mm, etc.) on your lenses and is the distance between the lens and the image sensor when the subject is focused. There is tons of information about the technical aspects of the focal length, and in this article, I am not going to go in-depth with these technical aspects.
Where Can you find the Lens Focal Length?
Usually, by looking around the lens barrel or the lens’s front, you would see many numbers, including the focal length followed by mm (millimetre). In the below pictures, I marked the focal length in two different lenses.
Lens Focal Length
Zoom lenses and Prime lenses
If the focal length is a range of numbers (e.g. 18-55MM), it means that you have a Zoom lens. A zoom lens is a lens with variable focal lengths. In comparison, a Prime lens is a lens with one focal length. A zoom lens can be a wide-angle, wide to telephoto or a telephoto zoom lens. It takes us to the next topic of Lens focal length and Angle Of View.
Zoom lens focal length
What is the Lens angle of View?
The angle of view reflects how much of a scene or subject a lens can cover and take the image. Expressed in degrees, the angle of view can be measured horizontally, vertically or diagonally across an image.
The angle of view depends on the size of the sensor as well as the focal length. The larger the sensor, the wider angle of view. For example, a 50mm lens has more angle views on a full-frame camera than an APSC size camera.
The general rule to remember.
To make it easy to remember, we should know that any focal length smaller than 35mm is considered wide-angle and any number higher than 50mm as a telephoto (in full-frame and APSC DSLRs).
Lens Focal length is 24mm
Lens Focal length is 50mm
Lens Focal length is 70mm
Lens Focal length is 200mm
Lens Focal length is 300mm
Lens Focal Length and Camera’s Shutter Speed
As a rule of thumb, the camera shutter speed should be higher than the focal length to avoid blurry photos (camera shake). For instance, if you shoot at a focal length of 85mm, the safe shutter speed is 1/90s faster to reduce the chance of a blurry picture.
Do you want to learn more?
I cover the Focal Length in-depth in our Digital Photography Bootcamp program. This six-week photography workshop consists of six classroom sessions and two field trips. It is a complete photography class for beginners to intermediate photographers who want to start photography as a business or just for fun and creativity.
That is all for now. Stay tuned for my next photography Tips. We love to hear from you. Let us know if you have any questions; feel free to send us your questions, and we will be more than happy to answer them. Follow us on Facebook, Instagram and Twitter for more Free Tutorials and Tips.
Ted and the Omnilargess Team