What Does MM Mean on a Camera Lens?

This article will discuss what the numbers and symbols on your camera lens mean.

When shopping for a new camera lens or looking at a lens I already own, I have always wondered what the etched numbers mean. “What does MM mean on a lens?” is just one of the several questions I have.

Fortunately, I extensively researched the numbers and symbols found on a lens. Below, I will discuss their meanings to help you purchase the right lens for your needs. 

I will also walk you through the different types of lenses based on the focal length used. And to sum things up, I will answer some of your frequently asked questions about lens abbreviations.

Read on to learn more about the lens barrel details!

What Does the MM Mean in Camera Lenses?

All camera lenses have an “mm” number etched on the body somewhere.

Mm refers to millimeters, which is the unit used to measure focal length.

Some lenses offer the option to adjust within a range of different focal lengths, for example 18mm to 35mm. However, other camera lenses only have one single length (also called fixed length).

The lenses with variable focal lengths are known as zoom lenses. They got their name because they allow you to zoom in or out to get closer or further away from the subject.  

Meanwhile, the fixed focal length lenses are known as primes. Prime lenses only have a one mm designation. Thus, they require you to move physically to get near or further from your subject.

Most photographers and videographers do not spend time studying the focal length of the lens. However, it is important to understand it to achieve the best from your lens.

What Is the Focal Length in Photography?

Let us discuss focal length in more detail to understand how it can affect your photos and videos.

The focal length is the distance between the camera and the lens when you have the subject in focus. As previously mentioned, this distance is measured in millimeters.

For instance, in a 35mm lens, there are 35 millimeters between the lens and the image sensor. In the case of zoom lenses like the 18 to 55mm, both the minimum and maximum focal lengths are already indicated.

Besides the technical definition of focal length, it is also essential to know what it shows us.

Focal length refers to the angle of view of a lens. In other words, it tells how much of the scene before us the lens captures and how large the subjects within the frame will appear.

The longer the focal length, the narrow the angle of view of the lens. The subjects will also appear larger than they do when viewing them with our eyes.

In contrast, lenses with short focal lengths offer a much wider angle of view. Thus, subjects can seem much smaller in the frame than they do to our eyes.

What Are the Different Types of Lenses?

There are different types of lenses based on the focal lengths they have. Each focal length can help you achieve a particular result.

Read on below to learn about the types of camera lenses that you can use to get the best picture or video possible.

Wide-Angle Lens

Wide-angle lenses feature focal lengths between 14mm and 35mm. As their name suggests, they offer a wider field of view than standard lenses.

Hence, wide-angle lenses can help you frame a scene at eye level to display beautiful landscapes and architectural structures. They are also ideal for capturing large groups of people, architecture, and interiors. See our top picks for landscape lenses if you have a Nikon camera body.

However, be careful when capturing people using a wide-angle lens. The subjects can appear smaller in the frame. But if this is your intended result, go ahead and buy a wide-angle lens for your photoshoot.

Telephoto Lens

Telephoto lenses offer 85mm or larger focal lengths. They decrease the angle of vision to turn a close-up into a long shot. They feature numerous optical features, such as multiple lenses and glasses, to bend light and focus on small things from a distance. Hence, telephoto lenses make the subject look closer even when taking a picture from far away. 

This type of lens is perfect when you want to close the distance between you and the subject. It is ideal for capturing wildlife, sports, and other interesting action from afar.

Telephoto lenses are further divided into sub-types, depending on the exact focal length.

Short telephoto lenses offer a focal length between 85mm and 135mm. They are suitable for close-up portraits and some street photography.

Medium telephotos have a focal length of 135mm to 300mm. They can help you capture wildlife and sports.

Finally, super telephoto lenses are those with 300mm and above focal length. They are ideal for astronomy and nature.

Standard Lens

A standard lens sits between a wide-angle lens and a telephoto lens. It is also known as the “normal lens” because it captures images close to what the human eyes see. Hence, the result looks natural to the person who sees it.

Standard lenses have a focal length of between 35mm and 85mm. They are great all-around lenses that can help you take close-up portraits and travel photos. They are also ideal for indoor, low-light, and street photography. 

Ultra-Wide Lens

Ultra-wide lenses offer a focal length of 10mm or smaller. As a result, they deliver a different sense of depth and perspective you cannot find in ordinary wide-angle lenses. They can fit much of the foreground in the frame and the surrounding elements within the scene.

They also let you shoot with a larger depth of field and shorter shutter speeds. Thus, they are ideal for capturing low-light environments such as sunsets.

Furthermore, the ultra-wide lens allows for more creativity. It can capture large-scale landscapes, architectural details, groups of people, and stage plays.

Overall, this type of lens is popular among landscape, architecture, and creative photographers.

Fisheye Lens

A fisheye lens is a type of ultra-wide angle lens. It has a focal length that can go as small as 8mm.

Hence, it lets you capture a large portion of the scene with a distinctive and distorted view. It creates a unique “fisheye” effect similar to a GoPro video, hence the name of the lens. 

Fisheye lenses are initially made to shoot surveillance videos. But today, they have various applications. They can help you photograph indoors or use your camera for abstract work. They are also ideal for landscape, architecture, extreme sport, and artistic photography.

Macro Lens

A macro lens offers varying focal lengths from 35mm to 200mm. But what sets it apart is its ability to focus closer than standard lenses. It is ideal for capturing small objects, such as insects and plants.

This type of camera lens can also capture fine detail in ultra-sharp focus. Hence, it is handy for taking portraits.  

What Do the Other Numbers and Symbols on a Camera Lens Mean?

Besides the mm designation on lenses, you might have come across other numbers, characters, and symbols.

Below, I will give a brief description of each one. Hopefully, this section will help you better understand camera lenses, so you can easily make a purchasing decision next time.

Ø Numbers

The symbol Ø on your lens refers to the diameter of the lens. It is the measurement, stated in millimeters, around your lens. For instance, Ø68 means that your lens has a 68-millimeter diameter.

It is essential to know the size of your camera lens, especially when you are planning to buy a lens cap or filter. Make sure to look at the product description and choose one with the same diameter. So if you own a lens with Ø72, you need to buy accessories with the same diameter.

Meters and Feet Numbers

You will also notice meters and feet measurements (#m / #ft) when shopping for a lens. They refer to the minimum focusing distance of the glass.

For instance, a camera lens with 0.9m / 2.96ft will focus at 0.9 meters or 2.96 feet. The numbers are equal, but they are shown in two different measurements. When you move this lens closer than 0.9 meters, you will not be able to focus on the subject.

If you have a zoom lens, the minimum focusing distance might be expressed in a range of numbers. In a lens with 0.5m / 1.64ft to 0.8m / 2.63ft, the focusing distance lengthens as the lens zooms in. The focusing distance at the widest focal length is 0.5 meters or 1.64 feet. Meanwhile, this becomes 0.8 meters or 2.63 feet when you are zoomed in on the subject.

It is important to understand the minimum focusing distance of the lens, especially if you like to capture subjects at a close distance.

Macro 1:1

Macro lenses allow you to photograph small subjects and focus on the fine details. They usually have a 1:1 designation. This simply means that the size of the subject you will capture is the same size as the image sensor. 

Besides 1:1 magnification, a macro lens can also offer a 2:1 ratio. It results in the subject being twice the size of the sensor.

If the lens has a 1:2 ratio, the subject will be half the size of the sensor.

Other Lens Features

Different camera manufacturers have unique letters or symbols stamped onto their lenses. These state any special features the lens may have.

For instance, both Nikon and Canon lenses use different letters for their focusing system. Canon calls them “USM” or Ultrasonic Motor, which offers a faster autofocusing performance. Meanwhile, “AF-S” stands for silent wave motor or quiet AF operation.

On Sony lenses, “G” stands for Gold, and it refers to the highest-quality version of a particular lens. Meanwhile, “OSS” distinguishes the lens for having built-in optical stabilization.

Some lens manufacturers also state whether the lens is a second or third version. These are usually stated with Roman numerals. They refer to an improved type of an older lens.

Frequently Asked Questions

Is a higher mm lens better?

A higher mm lens offers a bigger zoom, while a lower number means that the lens can provide a wider field of view. A higher mm lens might be better suited for your needs if you like to capture distant objects, such as wildlife or sports. It is also ideal for shooting close-up portraits, astronomy, and nature. This kind of lens is called a telephoto.

Which lens is better: 35mm or 50mm?

When shopping for a prime lens, you will encounter two common focal lengths—35mm and 50mm. 

The 35mm lens offers a relatively wide field of view. Hence, it allows you to fit more of the scenery within the frame. It is ideal if you are into street photography, architecture, and landscapes.

Meanwhile, the 50mm lens has a tighter field of view. It is difficult to use indoors due to the zoomed-in perspective. However, it is suitable for headshots and portraits.

Choosing between these two will depend on your needs and what you intend to achieve.

What does 200mm mean?

200mm refers to the focal length of a lens. A 200mm lens is considered telephoto. Hence, it has a narrow angle of view and increased magnification. It allows you to shoot wildlife, nature, sports, and other subjects from a distance.


That sums up this article about lens labels! I hope that you understood the meaning of “mm” on lenses. It refers to the focal length of the glass, which tells you how much of the subject the camera can capture.

Besides the “mm” designation, it is also best to look carefully at every letter and number of the lens. Each one tells valuable information about the glass, which can increase or decrease its value.