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You may wonder, what do the numbers on my camera lens mean? That’s what we are going to talk about today: the numbers on your lens and what they mean, and the different types of lenses and their uses.

Focal Length

Lens Measurements

On the front of the lens you will see a few sets of numbers, one of which is the lens’ focal length. The focal length is the distance between the lens and the image sensor when the subject is in focus. Generally, the length is measured in millimeters (e.g., 50mm). With zoom lenses, the focal range is stated with the minimum and maximum focal lengths (e.g., 24-70mm).

Lens Ratio

Also on the front of the lens is the lens ratio (e.g., 1:2.8), the maximum aperture of the lens. As we have learned from the post about aperture, it controls the amount of light hitting the image sensor. This means that if the camera has a lens ratio of 1:2.8, the maximum aperture of 2.8 will remain the same throughout the lenses focal range of 24-70mm. However, if you have a ratio such as 1:2.8-4, when shooting at the lens' widest measurement, 24mm, the maximum aperture is 2.8, and when shooting at 70mm, the maximum aperture is now at 4. This is common with kit lenses as they tend to have large focal ranges

Standard Zoom

Standard Lens

A standard zoom lens is a general-purpose lens that comes with most cameras, also known as the kit lens. The lens covers a range of focal lengths, somewhere around 18-55mm. If that is not a wide enough range for you, you can upgrade your kit lens with one that has a wider range, better photo quality, and a faster maximum aperture.

Telephoto Zoom

Telephoto Lens

Telephoto zoom lenses have a much longer focal length than standard zoom lenses. These lenses are great for being able to get much closer to your subject without having to be physically close. This is perfect for wildlife, sports, or even street photography.

Wide Angle

Wide Angle Lens

A wide angle lens gives you a wider angle of view, usually offers focal lengths between 10-24mm, enabling you to capture far-reaching vistas, which is excellent for landscape or architectural photography.


Prime Lens

Prime lenses have a fixed focal length, meaning they don’t have zooming capabilities. You may wonder why you would want to buy a lens that is so restricted. Compared to a zoom lens, prime tend to be smaller, lighter, have a faster maximum aperture, and produce sharper images. Prime lenses are great when shooting in low light and when you want utilize the fast maximum aperture.


Macro Lens

Macro lenses allow photographers to take extreme close-up images. They're perfect for capturing detail on the smallest of subjects, like insects or flowers. Macro lenses are also great for portraits. As with prime lenses, macro lenses have a fixed focal length.


Fisheye Lens

Specialty lenses, such as fisheye and tilt-shift lenses, are certainly not for everyday use, but do create very interesting and creative shots. Fisheye lenses create a distorted circular image in a wide-angle view. Tilt-shift lenses allow for selective focusing, selecting a specific part of the image to be in focus.

Whether or not you are a serious photographer, it’s definitely worth investing in quality lenses. Lenses last longer than cameras and can be used on newer camera bodies. Take the time and select the right lenses for you. Don’t be afraid to spend a little money, guaranteed you will be happy with the results. Happy shooting!

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