Even if cell phone cameras keep improving and reach unimaginable levels of image quality, I’ll always carry around a larger, heavier, and more complex camera. Why is that? One word: lenses! An interchangeable lens camera opens up a vast world of photographic visions through a huge variety of optics. Choosing among the dozens and even hundreds of lenses can be confusing and intimidating, so in this beginner’s guide, I’ll explain the types of lenses available and what you should buy.
Table of Contents
What Does a Lens Do?
A lens focuses light to form an image on the camera’s digital sensor or film plane, much the way our eye works. And importantly, a lens determines how much of the subject is seen and captured, from the broad sweeping view of a wide angle lens to the narrow, selective view of a telephoto lens. We call this the angle of view.
Lenses are classified by their specific focal length in millimeters. At the simplest level, this millimeter marking corresponds to the distance between the lens’s optical center and the camera’s image sensor when focused. From that focal length designation, we know how an image will look – in particular, the angle of view – on a given camera. Focal length is the most important factor to determine which lens to use for a given photo.
Note that the images above are taken with a full-frame camera – i.e., a camera with a sensor that’s about 24×36mm in size. If your camera has a smaller sensor like aps-c or Micro Four Thirds, it will act as a “crop” of the images above and give a more zoomed-in appearance at each focal length. To be specific, aps-c cameras have about a 1.5× crop factor, and Micro Four Thirds cameras have about a 2× crop factor. (For the remainder of this article, any time I mention specific focal lengths, I’ll be doing so in terms of a full frame camera. To get the equivalent number on your camera, it’s as easy as dividing by your crop factor.)
Along with focal length, a lens also has a diaphragm that can change size – commonly called aperture – which controls how much light is let through the lens (part of how we control exposure). As your aperture changes, it looks like this:
Every lens lets you change the aperture size, so you’re not stuck at one aperture. However, lenses are usually named by their maximum aperture because it’s so important – for example, the Nikon 28mm f/2.8 has a 28mm focal length and a maximum aperture of f/2.8. Other lenses have maximum apertures of f/4 or f/5.6 (which don’t let in as much light), and some go the other direction to f/1.4 or f/2 (capable of capturing much more light).
Aperture doesn’t just change how much light you capture. It also determines how much of our subject is in focus from front to back – what we call depth of field. As the aperture narrows, depth of field increases, which is why landscape photographers often use apertures like f/8, f/11, or f/16 to get sharp focus from front to back.
Combined, these two factors – focal length and aperture – are the most important features of a lens. If you know a lens’s focal length(s) and maximum aperture, you already know a great deal about what subjects it’s intended to capture. I’ll cover more about those intended subjects next.
The Normal Lens
Lenses with a “middle” focal length – not super wide, not super telephoto – are known as normal lenses or standard lenses. Many photographers swear by the normal lens as their main tool because it does not exaggerate perspective and can be pressed into service for a wide variety of photographic needs. Photos taken with a normal lens feel like looking at the world with your eyes, not a camera.
The normal lens for a given camera system has a focal length similar to the diagonal length of that camera’s sensor or film. Full-frame cameras (again, with a roughly 24×36mm sensor) have about a 43mm diagonal. The classic normal lens on full-frame is a 50mm, which is a bit longer than 43mm but pretty similar.
Normal/standard lenses were almost always sold with the camera as a kit in the film days of decades past. Today, there are still plenty of 50mm lenses available from each manufacturer (or equivalents for smaller sensors like 35mm and 24mm lenses).
Everything from family candids, low-light street scenes, wedding group photos, and even landscapes look natural with a normal lens. It’s a flexible tool.
Wide Angle Lens Drama
Wide angle lenses can be exciting to look through, as they take in a much more expansive view than the normal lens and can be used to exaggerate perspective in pleasing ways.
A typical use for a wide angle is in a dramatic landscape, where the wide field of view allows you to get close to an interesting foreground such as a field of wildflowers, while still capturing a sweeping view of the mountains in the background. Wide angles are also commonly used in architectural photography, such as including all of the grand interior of a cathedral in the photograph.
On full frame, wide angle focal lengths range from about 10mm (uncommon and excessively wide for many uses) to 35mm (which is long enough that some photographers consider it a normal lens rather than a wide-angle).
Telephoto Lens Power
A telephoto lens is like looking through binoculars – it has the power to bring your subject up close and personal. A telephoto has a selective angle of view and is commonly used to photograph more distant subjects such as wildlife or sports. It can also make pleasing head and shoulders portraits of people from a relaxed and comfortable distance.
If you can’t get close to your subject, chances are you will want a telephoto lens. They are my personal favorite lens type for landscapes, where I can compose a picture of a photogenic section of a forest rather than taking in the entire hillside. Telephoto focal lengths begin at 70mm and continue up to about 800mm.
Within the broad categories of wide angle, normal, and telephoto lenses, there are also more specialized optics. For example, a macro lens is designed to focus very close so that tiny objects such as insects, flowers, or jewelry can fill the frame. Another specialty lens is the high-speed (or fast) lens, which has larger lens elements and a wider maximum aperture – great for letting in more light and capturing very shallow depth of field photos, where not much in the image is in focus.
Other speciality lenses included fisheye with its extreme and distorted field of view, tilt/shift lenses which are used by some architectural, studio, and landscape photographers to more precisely control perspective and focus, and the huge, exotic super-telephotos seen on the sidelines of major sporting events.
Primes vs Zooms
A prime lens has a single focal length, such as the 50mm normal lens. A zoom lens has a range of continuously variable focal lengths, such as a 24-105mm lens. You turn the zoom ring on the lens barrel to zoom in from a wide-angle 24mm perspective toward a telephoto 105mm.
Prime lenses are often smaller and lighter than zooms, and they often have a larger maximum aperture. Prime lenses also tend to provide somewhat better optical quality than zooms. But zoom lenses win the convenience award, allowing you to carry one lens that replaces a whole bag of fixed focal length primes.
The very best zoom lenses these days are so good optically that most photographers will not need to worry about the optical differences. Both primes and zooms can have their proper place as a photographer’s lens kit grows.
Price vs Performance
Lenses come in all price ranges, and good options exist in the budget range. Spending more money may get you a higher level of build quality, more refined optical qualities, or wider apertures, but for the beginner, there is no reason to overspend.
Any modern lens should allow you to take pictures as excellent as your skills allow. If you do continue to enjoy photography and develop your skills, a time may come when spending more money will get you an upgrade in one of the aforementioned areas.
OEM vs Third Party
Each camera manufacturer such as Canon, Nikon, and Sony has its own line of lenses designed to fit its specific cameras, and most of these lenses tend to be very good to excellent and are a safe choice. But there are also third-party, lens-only manufacturers such as Sigma and Tamron who are turning out great optics and usually at lower prices than the OEM lenses. Perusing the lens reviews here at Photography Life will help give you ideas of what lenses are available and how they measure up.
New vs Used Lenses
New lenses are a safer bet as you usually have 30-day return privileges if not satisfied, and you don’t have to wonder how the lens was treated by previous owners. You also have a manufacturer’s warranty if you purchase from an authorized dealer for the brand you choose.
For bargain hunters, used lenses can bring the reward of money saved, but there is the risk of getting a lens that does not perform as it should. There are a wide variety of potential issues with precision products like lenses, such as a lens element that is out of alignment, autofocus motors dying, dust or mold inside the optics, or wear and tear on the barrel.
I advise beginners to buy new, or make sure there is a return privilege for used lens purchases purchased from a reliable seller (B&H Photo is an excellent choice for new and used; KEH Camera is great for buying used with good warranty).
Choosing One Lens to Start With
Armed with this basic introductory info about lenses, now the fun begins: choosing your first one.
The classic, disciplined approach argues for a 50mm normal lens, and these have the advantage of being among the most affordable, lightweight, small, bright (AKA wider aperture), and optically excellent lenses in any manufacturer’s line. As a beginner, using a 50mm lens for a wide variety of photography will teach you much about what your own needs are for your ultimate lens kit. If you photograph in small spaces, you may eventually see the need for a wide angle, or if you spend much of your photography taking pictures of children’s soccer, you’ll soon understand the need for a telephoto. A 50mm standard lens is a great teacher.
If you want to photograph a wide variety of subjects with convenience, a more versatile first lens purchase would be a wide-to-telephoto zoom, something like a 24-105mm or 28-200mm. With zooms like this, you’ll have all the most important focal lengths covered in one package, and you just need to turn the zoom ring to find the right perspective for your subject.
The more modest the zoom range, the better optical quality tends to be. 24-70mm lenses usually beat 24-120mm lenses, which usually beat 24-200mm lenses. (They also tend to be lighter and/or have a larger maximum aperture.) I find that 24-105mm and 24-120mm lenses are the best compromise. They’re not just a good first lens for beginners, but also a beloved optic any time you need a versatile lens on your camera. I use a 24-120mm f/4 constantly on my own system.
To add a bit of discipline as you’re starting out with a zoom lens like this, I recommend a beginner take the 24-105mm zoom and for the first few months of their photography only use the lens at three marked focal length settings: 24, 50, and 105mm. It will be as if you have three primes in your bag, and you’ll learn from this exercise how to choose the focal length to suit the perspective and composition you want for each subject.
If you are a beginner who already knows you are going to be spending most of your camera time photographing sports or wildlife, and you only want one lens to start with, then consider bypassing the wide and normal views and choose a 70-300mm or 100-400mm as your first lens. This way you are equipped with the telephoto range needed for distant subjects, and you can use your iPhone for the normal and wide views when taking family snapshots or vacation pics.
Building A Multi-Lens System
Here’s where it gets more fun! If you plan from the start to build a system of two or more lenses, you can expand on my recommendations above and use multiple lenses that complement each other.
If choosing the versatile 24-105mm recommended above, lens number two (when you’re ready) could be a 100-400mm to get a telephoto perspective, a 50mm f/1.8 to get a wider aperture, or a 16-35mm to get a wider angle view.
Alternatively, nature lovers may eventually want a macro lens to help capture close-ups of the tiny world, and a 100mm macro is a superb complement for almost any other lens kit. Since most macro lenses have a large maximum aperture of f/2.8 or so, they can also double as a portrait lens that offers a nice, shallow depth of field effect. Or you can go to more exotic fast-aperture primes if portraiture is your specialty, such as a 85mm f/1.2 or 135mm f/1.8.
Enjoy the View!
Lenses are the life of the interchangeable lens camera, and truly the best way for a beginner to expand their vision through the virtually limitless world of optics. From the drama of wide angles, to the just-right comfort of the standard lens, to the powerful world of telephotos, the view from a good lens is seductive and just may lure you into the joy of photography for the rest of your life.
I hope you’ve glimpsed the fun that can await you as a beginner looking to choose your first lens or build a multiple lens system. I welcome your comments below!