What Do the Numbers and Letters on a Camera Lens Mean?

So you just bought a new DSLR, unpacked it ready to capture the world, and to your surprise, there are many numbers and letters on it.

But not to worry. It can be overwhelming for a beginner starting out in photography.

In this guide, we want to help you understand your camera better so you can get the best out of it. 

So What Do the Numbers and Letters on a Camera Lens Mean?

What are those camera lens markings?

Alright. Let’s get into details and unveil what each number and letter means or stands for.

Focal length

This is perhaps the most important number you should care about.

Focal length directly impacts the angle of view meaning you could get more or less in a shot. The number is usually written as a range, for instance, 10-20mm.

10mm is considered the lowest focal length. You can spot it on many extreme wide-angle lenses for architecture.

The perfect spot (read as average) for everyday normal situations is between 50-70mm. Anyone who is not sure what focal length they need can start from there.

A focal length between 70 and 100mm is great for portraits and children photography.

Lenses that go beyond 100mm (telephoto and super-telephoto) are for long-distance shots and are common among wildlife and sports photographers. 

Prime lens

If your lens has just a single number, like 50mm, then that’s a prime lens. It’s not advisable to go for such a lens.

And if you must have one, then make sure to get zoom lenses as well for when you want to bring image details closer or far.

Basically, with focal length, the higher the number, the less you can fit into one shot. Meanwhile, the lower the number the more details you can get in a shot. 

Moving on to the next.

Aperture size

An aperture is the opening through which light enters the camera. It’s usually printed as f/2, f/2.8, f/5.6, etc.

Without getting too technical about how the ratios are arrived at, just know that smaller numbers mean a wide aperture.

Conversely, bigger numbers indicate less exposure.

There are instances where a camera comes with two aperture numbers printed on its lens.

This usually indicates that you can zoom the aperture in and out within a specified range. How far you can zoom will also be determined by the focal length.

Lens diameter

Understanding letters and numbers on a camera lens

If you see a symbol that looks like a circle with a slash through it, followed by a number, that is the diameter of the lens.

It will guide you in knowing what filter size to buy.

Lens diameter, like focal length, is in mm and the common choices are Ø 77 mm and Ø 82 mm.

Full frames and crop sensors

Cameras are either full-frame or crop sensors.

Full frames can work with a variety of lenses and are characterized by a wide field of view.

Crop sensors, on the other hand, work mostly with crop sensor lenses with a fairly smaller field of view.

To make buyers know what they want immediately, lenses manufacturers print the following symbols on their optics:

  • The DG-full frame (Sigma brand)
  • DC- crop sensor or 1.5/1.6 (Sigma brand)
  • The EF-full frame (Canon brand)
  • EF-S or crop 1.6 (Canon brand)
  • FX DX or crop 1.5 (Nikon brand)
  • 1 Nikkor or crop 2.7 mirrorless (Nikon)
  • Di Di II or crop 1.5/1.6 (Tamron brand)
  • Di III or crop 1.5/2 (Tamron brand)
  • Unmarked DT crop 1.5 (Sony)

Lens version

Have you ever seen a lens with “II” or “III” on it?

This usually means it’s the second or third version and therefore sports more advanced features than the former.

It’s just the same way software engineers list their version updates as v2 or v3. So the bigger the number the better the shooting experience.

Image stabilization

Another symbol that is frequently stamped on camera lenses is image stabilization.

Your camera should have it. If stabilization is missing then you must prioritize lenses that come with one.

Unlike focal length and other common symbols, camera manufacturers handle image stabilization differently. Therefore, the symbols differ greatly.

Here is what you’ll see most of the time:

  • Nikon- VR (Vibration Reduction)
  • Sigma-OS (Optical Stabilization)
  • Canon-IS (Image Stabilization)
  • Tamron-VC (Vibration Compensation)
  • Sony-OSS (Optical SteadyShot)

Focusing motor type

Some cameras come with three letters etched somewhere on the lens such as HSM, USM, or SWM.

In their absence, you’ll possibly see “Ultrasonic” or “hypersonic.” They usually indicate the type of motor the camera has and how fast and quiet it will run.

It’s important to note that “Ultrasonic” or “hypersonic” does not necessarily indicate exceptional working standards as this varies from one manufacturer to the other.

Always do your research and read customer reviews to get a good idea of what you might get.

Final Thoughts

That’s it for now. You should be able to know what the symbols, letters, and numbers on your camera mean. Toodles.