If you’re a beginning photographer, you may wonder what is the meaning of numbers on Camera Lens? It’s actually not difficult to understand all numbers and letters on Camera Lens. Now we break it down for you.
Focal Length – Meaning of numbers on Camera Lens ↑
The focal length of your lens essentially determines how ‘zoomed in’ your photos are; the higher the number, the more zoomed your lens will be. There are two type of Lens you should know, Prime Lens and Zoom Lens. The numbers of Focal Length write on each type are different.
If the name of the lens has two numbers, it means that’s a zoom lens. For example: “70-200mm” means that when the lens is at it’s ‘shortest’ or ‘widest’, it’s an 70mm lens. When fully extended, ‘zoomed’ or ‘long’, it can go up to 200mm. And of course, it have a ring on lens body for adjusting focal length. In case of picture below, the current focal length is 100mm.
A prime (some people call it ‘fixed’ lens) is one which doesn’t zoom in and out, but stays fixed at a certain length. Examples: “Canon 50mm f/1.4 USM”, the 50mm part means that the lens stays fixed at 50mm. Other popular ones are 24mm, 85mm or 200mm.
Aperture – Meaning of numbers on Camera Lens ↑
Aperture is like how wide open the pupils of your eye are. The more wide open the more light is let in. The more closed the aperture and the less light. The aperture of a lens is measured in f/stops. Once f/stop is minimum, it’s widest open. Otherwise, f/stop is maximum, it’s closest narrow.
Aperture on Primes will be one such number. For example: 50mm f/1.4. The focal length is 50mm and the most wide open aperture you can get on that lens is 1.4.
Aperture on Zooms is usually a range (two f/stop numbers). it’s much like the two numbers to tell you the range of the focal length. Example: “Canon EF-S 18-55mm f3.5-5.6 IS STM”, it means that when the lens is at it’s widest (or shortest) 18mm, the min f/stop can be down to 3.5. When it’s zoomed all the way to 55mm, the min f/stop is 5.6.
Remember that some Zoom Lenses have only one f/stop number.
Minimum Focus Distance ↑
The minimum focus distance is the shortest distance at which a lens can focus. In the case of DSLR Cameras, the distance to the subject is measured from the focal plane mark on the camera body, not from the front of the lens.
Different lenses have different minimum focus distances. The minimum focus distance of an AF-S DX NIKKOR 18–55 mm f/3.5–5.6G VR lens is 0.28 m or 0.92 ft. (a little over 11 inches; this information appears on the lens as ∞–0.28 m/0.92 ft.).
The minimum focus distance of an AF-S NIKKOR 50 mm f/1.4G is 0.45 m (about 1.5 feet or 18 inches; the minimum focus distance is shown in the lens focus distance display).
Filter Size – Meaning of numbers on Camera Lens ↑
Look at every Lens. You always see letter Φ. That’s meaning the size of filter you can put on your lens.
For example: The Lens below have Φ77mm . So you should buy a filter with size is 77mm.