A camera lens is essential to taking sharp high-quality photos. With so many options out there, narrowing down what lens to buy for your DSLR, mirrorless, or interchangeable camera can get confusing. Our in-depth camera lens guide will break down the key features and terms to help you find the best lens.
Camera Lens Features
When you look at a camera lens description, it’s easy to get overwhelmed. It almost seems as though lenses were named by dumping a can of alphabet soup and using whatever fell out. What does Nikon 10-24mm f/3.5-4.5G AF-S DX ED mean? How about Canon EF 100-400mm f/4.5-5.6L IS II USM?
Once you learn the characteristics of a lens, and some of the idiosyncrasies in each brand’s naming scheme, you’ll see the name of a lens tells you a lot.
A critical characteristic of a lens is its focal length. The focal length is indicated by the numbers immediately before the “mm” (millimeter) marking in the lens name. Prime lenses (such as a 50mm) are fixed at one focal length and so have only one number. Zoom lenses (such as a 24-70mm) will list the far ends of their focal length range.
When you’re choosing a lens for a specific function, keep in mind that the sensor in your camera will impact the apparent focal length of a lens. A lens that is wide angle on a full frame camera might be “normal view” on a crop sensor.
Another important characteristic of a lens is its maximum aperture. In the lens name, this is the number that comes after the “f/” marking. Like with focal length, it might contain a single number (e.g., f/2.8) or a range of numbers (e.g., f/4-5.6). Single numbers are given when the lens is a prime lens or if the maximum aperture is the same across the entire zoom range. Multiple numbers are given if the maximum aperture changes as you zoom the lens.
One of the best innovations in modern photography is image stabilization. An image stabilized lens uses some sort of mechanism (usually gyroscope sensors or some variation of floating lens elements) to compensate for shakes when hand holding the camera. This allows you to use slower shutter speeds in dimly lit situations to prevent handshake blur.
Each lens manufacturer has a different name for their image stabilization system:
- Canon – Image Stabilization (IS)
- Nikon – Vibration Reduction (VR)
- Sony – Optical SteadyShot (OSS)
- Sigma – Optical Stabilization (OS)
- Tamron – Vibration Compensation (VC)
- Fuji – Optical Image Stabilization (OIS)
On most (or all) lenses, there’s some designation as to whether the lens is for a full frame or a crop sensor. Most of the time, you can use full frame lenses with no problem on crop sensor cameras, but you generally can’t use crop lenses on full frame cameras because the image won’t cover the entire sensor.
The lens mount is the connection between the lens and camera body. Lenses from one camera body maker will not fit directly onto the body of another camera body maker (though there may be an adapter that you can use).
Some camera and lens manufacturers are incredibly consistent with their mounts. Canon EF lenses, for example, will mount onto any Canon camera since they transitioned to autofocus. Other manufacturers will have multiple mounts for different camera body lines, such as Sony’s A and E mount cameras.
Other Common Lens Features
While the features above are probably the most important, they are not the only ones you will see on your lens. Some other markings you may see include:
Autofocus Motor Designation
As lens manufacturers made improvements in the quality of the motors used in their autofocus systems, they started using the motor (and its designation marking) as a selling point. In currently produced lenses, the top-tier AF motors include USM (Canon), AF-S (Nikon), HSM (Sigma), LM (Fuji), and USD (Tamron).
Some newer Canon lenses are being produced with a new autofocus motor called Stepper Motor (STM) that is designed to be smoother and silent during video shooting. STM lenses do sacrifice a little focusing speed for these advantages, making them better suited for video than any still shooting that requires fast focusing such as sports or wildlife.
If a lens from one of these manufacturers doesn’t include that designation, you can assume that the autofocus will likely be slower and noisier.
Glass Element Descriptor
There are a lot of different designs and materials used for the glass elements inside of a lens. Some companies don’t often list this, while others have a variety of element types and add the description to all of their product names, which can make it difficult to keep track of what they mean. Some element descriptors you might see include UD (Canon), ED (Nikon, Sony), EBC/Super EBC (Fuji), XR (Tamron), and ASP (Sigma). Because of the enormous variety of element descriptors, check the manufacturer’s information for details about a given element type.
Lens Line Designation
There is a wide spectrum of lens qualities available from every manufacturer. Each manufacturer has its own method of distinguishing which of its lenses are the top-of-the-line. These pro-level lenses often have better build quality, wider apertures, better image stabilization systems, or other features targeting the needs of professional photographer.
Canon: Canon’s top-of-the-line lenses feature an “L” designation as well as a red ring around the end of the lens.
Nikon: Nikon doesn’t have a special letter or name designation for their top-tier lenses, but they can be identified by a gold ring around the end of the lens.
Sony: Sony uses a “G” designation for their pro line of lenses. You’ll also see “GM” for G Master.
Fuji: In Fuji’s G-Mount line, XF indicates the top tier lenses while XC indicates budget oriented lenses.
Sigma: Sigma recently came out with three distinct lines of lenses named Contemporary, Sport, and Art (designated C, S, and A).
- Contemporary (C) – Sigma’s prosumer lenses, offering premium optical quality while sacrificing somewhat on build quality to be more affordable and lightweight.
- Sport (S) – Top quality lenses targeting the needs of pro sports photographers (typically long lenses with wide apertures). There are currently only three S lenses.
- Art (A) – Sigma’s professional series designed to go toe-to-toe with Canon L and Nikon Gold Ring lenses.
Lens Version: On some lenses, you will see a Roman numeral designation to indicate when a manufacturer releases an updated and improved version of an existing lens line.
Macro/Micro: Macro photography is shooting extreme close-ups of a subject. By definition, a true macro lens will reproduce an image onto a sensor at least full size (1:1). In other words, an object the same size and shape as a 35mm sensor would fill up the entire 35mm sensor when photographed. Most lens manufacturers designate macro lenses with the word “Macro”, though Nikon uses “Micro” instead.
TS-E/PC-E: Tilt shift photography is a fairly niche area that requires specialized lenses. These are indicated by Canon as “TS-E” and by Nikon as “PC-E.”
Common Camera Lens Features
[table id=lens-naming /]
*Check with a specific lens manufacturer for markings not listed.
Understanding a Camera Lens Name
When you learn the camera lens features that make up its name, you’ll have a good idea of what the lens will be like.
Nikon 10-24mm f/3.5-4.5G AF-S DX ED – This is a Nikon lens with a focal length of 10-24mm. It has a variable maximum aperture of f/3.5 to f/4.5 depending on the focal length used (f/3.5 being the widest you can go at the wide end of the focal range and f/4.5 being the widest you can go at the long end of the focal range). The G means that aperture is set by the camera and not manually with a ring. The AF-S indicates it’s Nikon’s top autofocus system. It’s a DX lens, so it’s made for crop sensor cameras, and ED is Nikon’s top glass quality.
Canon EF 100-400mm f/4.5-5.6L IS II USM – This is a Canon EF lens, meaning that it’s designed for full frame cameras, though it could be used with a crop sensor lens. The 100-400mm focal length makes it a telephoto zoom and it has a variable maximum aperture from f/4.5 to f/5.6. The L designation places this in Canon’s pro line of lenses and it has both image stabilization (IS) and Canon’s top autofocus system (USM). The Roman numeral II indicates it’s the second generation version of this lens. And if you’re more interested in Canon lenses, make sure to check out our recent video review of the best Canon telephoto lenses below:
Once you learn the lens naming scheme, you can understand a lot about that lens just by reading the name.
More Camera Lens Features
These camera features may or may not be indicated on the lens itself, but they are typically readily available.
Lens Size and Weight: Generally speaking, lower quality lenses will be smaller and lighter while higher quality lenses will be larger and heavier. Pro level lenses are often made with metal instead of plastic and have larger glass elements to deliver wider apertures. If size and weight is a concern for you, consider a lighter lens. For example, there are landscape photographers who hike and are concerned about weight who choose Canon’s 70-200mm f/4L non-IS lens instead of the larger, heavier 70-200 f/2.8L IS because it saves weight while still offering pro-level quality.
Weatherproofing: One of the features of many higher quality lenses is better weatherproofing to protect your gear if you get caught in the rain or other extreme environments. If you are shooting in situations where that’s a concern, you should look for better weatherproofing. If you’re only shooting indoors or in other controlled environments you might be able to save money by choosing a lens without weatherproofing.
Filter Size: Somewhere on the lens there will be a circle with a line through it followed by a number (with or without “mm” after it). This is the diameter of the end of the lens and tells you what size screw on filter you need.
Types of Camera Lenses
Lenses are generally categorized by their focal length. What focal length you need is going to depend on your subject and personal style.
Ultra Wide Lenses
While there’s not a clear-cut definition of what’s considered an ultra wide lens, most will say that on a full frame camera, any lens shorter than 24mm fits into that category. Ultra wide angle lenses are used when you need to capture a lot of the surrounding space, especially when if you’re in a tight area where you can’t back up.
Ultra wide angle lenses need to be used carefully because they can easily introduce significant amounts of perspective distortion. You need to be careful about what lens you choose. They can either keep the image fairly straight or can cause the edges to bend (as with a fisheye lens). Learn more about this in Rectilinear and Fisheye Wide Angle Lenses Explained.
Wide Angle Lenses
Wide angle lenses are lenses with a focal length of 35mm or less on a full frame camera. As with ultra wides, they are used to fit a lot of the surrounding environment into the frame. They are still likely to introduce some distortion, but not as significantly as with ultra wide lenses.
Normal (Standard) Lenses
Normal lenses get their name because they most closely replicate what your eyes see. A normal lens field of view lacks perspective distortion present in wide angle lenses. You also won’t see the the flattening effect that comes with a telephoto lens. Your end result is a very natural looking shot between different objects and sizes.
On a full frame camera, normal focal length is somewhere around 50mm, but most lenses between 35mm and 70mm are considered “normal”.
Any lens that is longer than 70mm is considered to be a telephoto lens. This means that you can have lenses that are only slightly telephoto (such as the Canon EF 85mm f/1.2L II USM Lens) all the way up to giant beasts, such as the Nikon AF-S 800mm f/5.6E FL ED VR Lens. With telephoto lenses, you are going to largely choose a focal length based on what subject you’re photographing.
Shorter telephoto lenses are great as portrait and headshot lenses because they eliminate the distortion that comes with shooting close-ups with a shorter lens. Longer lenses are used when you need to fill the frame with a subject that’s more difficult to get close to, such as in sports or wildlife photography.
Often, when people refer to something with the label of zoom they think of it being highly magnified. For example, if you zoom into something on your computer, you are magnifying it.
When talking about lenses, zoom does not hold exactly the same meaning. Zoom lenses are simply lenses where you can change the focal length.
Zoom lenses offer a lot of flexibility because you are not limited to a single focal length. If you’re a little closer or farther away from the subject than you want to be, you can simply twist the ring and find the perfect focal length. The tradeoff is that zoom lenses are generally more expensive. They often don’t give as high of quality as a fixed prime lens in the form of fast apertures. Smetimes even edge-to-edge sharpness is sacrificed.
Macro lenses are made to photograph small objects at close distances with the biggest magnification possible. They achieve this in part by (generally) being telephoto lenses (though there are shorter macro lenses). But they are also built in a way that allows them to focus closer than most lenses. This allows you to fill the frame with a very small subject that’s close to the camera. Common subjects for macro photography include flowers and insects.
Camera Lens Types
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Best Camera Lens
Many people, especially beginners to interchangeable lens cameras, just want to know what the best lens is.
When choosing a lens, you need to consider a variety of factors. What focal length do you need for the subjects you’re shooting? Do you need a wide aperture to shoot in low light or blur the background? Do you need the most robust build quality or would you need something lighter and easier to carry around?
A camera lens is just one of the many tools you can use to help elevate your photography. Equip yourself with the right tools and you’re on the right track to consistently creating better images. Learn the qualities and characteristics of different lenses to help pick a camera lens that’s best for you and your style of photography.Tags: Best Portrait Lens, Canon Lenses, Portrait Photography Last modified: July 7, 2021