A Primer on Prime Lenses

For photography enthusiasts seeking to expand their horizons from pictures made with a mobile phone or a point-and-shoot, the major benefit in of upgrading to a DSLR or mirrorless camera system is the ability to swap out different lenses to fit your specific needs. Prime lenses are available in all lengths and varieties and offer numerous advantages in performance when compared to their zoom-lens brethren. Also, the particular choices associated with sticking to a specific focal length can help improve your photographic technique, as well as help you learn. And, a new prime lens can expand your capabilities with features such as a larger aperture for more effective low-light shooting or a specialized capability that enables you to get the close-ups you’ve always dreamed about.

Prime versus Zoom

Zoom lenses are incredibly convenient. They cover a wide range of focal lengths in a single package, and you don’t have to waste time constantly swapping out lenses to create the composition you desire. However, this huge strength also becomes their weakness. Designing a lens for optimal performance at multiple focal lengths is difficult, meaning that there will be some trade-offs in performance and size. Not to say there aren’t good zooms—there are—but they usually come with a premium price tag.

On the other hand, prime lenses are optimized to a specific focal length or purpose. This means that optical performance is generally much better and that the lenses can be made with larger apertures while still maintaining a fairly compact size. Another benefit is that a prime lens will have fewer moving parts, so there is less of an opportunity for problems to appear from general use. Generally, primes perform better than their zoom counterparts and are sharper, with fewer visible aberrations. These differences can be very apparent, especially with the high-resolution sensors currently available in modern DSLR and mirrorless cameras.

Another major difference is the inability to zoom for changes in composition. This requires a photographer to be more thoughtful in their process and to move around a bit more, since they can’t rely on a zoom lens to change perspective. This makes choosing a focal length one of the most important decisions when considering a prime lens.

Choosing a Focal Length

Different focal lengths are better suited to certain subjects or styles; this is why you will constantly see lenses like the 85mm referred to as a “portrait” lens, or the 35mm as a “street” lens. This has a lot to do with field of view and what you need the lens to do. Capturing cramped interiors will be the domain of the wide or extreme wide-angle lens, whereas distant wildlife or sports will obviously require the use of a telephoto lens.

Besides the obvious, different focal lengths have their own attributes and looks. For example, the longer the lens is, the shallower the depth of field will be when compared to a wider lens at the same aperture setting. The background of an image made with a 100mm lens at f/2.8 will be less distinct than that of a 35mm at f/2.8. Also, telephoto lenses tend to flatten features and compress space, making the background elements appear much closer to the subject than a wide-angle lens would. This is why an 85mm is a popular choice for portraiture; it has good background separation due to shallow depth of field and will flatten a subject’s features slightly for a more flattering image. Wide angles will exaggerate perspective, and will make subjects appear distorted, but they can capture a larger area and are well suited to architecture, landscapes, and other types of photography where dramatized elements are wanted.

 

Keep in mind that sensor size will affect the effective angle of view captured, and that lenses are commonly given a 35mm equivalent focal length for use with different formats, such as a DSLR with an APS-C sensor. A 50mm lens mounted on such a camera, with a 1.5x crop factor, for example, will have an equivalent focal length of 75mm. This doesn’t mean that the specific qualities of the lens have changed, a 50mm is still a 50mm, just that the area captured is similar to that of a 75mm lens on a full-frame camera, as if you had cropped the image in post.

A benefit of this is that users can enjoy more reach from their longer lenses. This can convert already far-reaching lens options to longer equivalent focal lengths, which may not be available otherwise. For example, Nikon’s AF-S NIKKOR 600mm f/4E FL ED VR lens or Canon’s EF 600mm f/4L IS III USM become equivalent 900mm and 960mm lenses respectively, which is longer than either company’s current longest lens at 800mm.

Some manufacturers take the popularity of crop-sensor cameras into account when making lenses. This means that some prime lenses work properly only on APS-C or smaller sensors and will not provide full coverage when using a full-frame camera. This does allow lenses to be much smaller than what is required to achieve equivalent focal lengths with a full-frame lens. FUJIFILM does this with its APS-C mirrorless camera series by releasing 23mm, 35mm, and 56mm lenses, which are equivalent to the popular, 35mm, 50mm, and 85mm lenses on full-frame cameras.

However, if you do own a crop-sensor camera and your brand offers full-frame options, you should consider whether you would like to eventually upgrade to the larger sensor later on. If so, crop-sensor lenses will not work on your later camera, though full-frame lenses will work properly on crop-sensor cameras. Purchasing full-frame-compatible glass now can save you time and money later.

There are other features, such as maximum aperture, minimum focus distance, and autofocus motors, which play a significant role in any final lens choice, but focal length remains the most important consideration.

Standard Lenses

One of the most common options for prime glass is the standard or normal lens. These lenses have an angle of view close to 45°, which replicates the perspective seen by our eyes. This is a good first lens for beginners because it is easy to imagine what your images will look like before you even put the viewfinder up to your eye. In 35mm terms, these lenses fall between 40mm and 65mm, though the 50mm is the most popular and well-known option.

Many prominent photographers have claimed the “nifty fifty as their favorite lens, such as Henri Cartier-Bresson, one of the most important photojournalists of the Twentieth Century, and an icon for amateur and professional street photographers. He famously used a 50mm lens almost exclusively for its ability to act as “an extension of (the) eye,” permitting photographers to trap life in a frame that resembles the way we experience the world.

Normal primes are also well liked because they are easy to manufacture, inexpensive, and generally reliable due to their simple design. Also, manufacturers tend to make multiple varieties of this lens for all levels of photographers, be it beginner, amateur, or professional. Lenses like Nikon’s AF-S NIKKOR 50mm f/1.8G and Canon’s EF 50mm f/1.8 STM are great budget options with wide maximum apertures that can dramatically expand a beginner’s capabilities compared to a kit zoom lens. And, for more advanced needs, there are higher-quality optics like ZEISS’s Otus 55mm f/1.4 lens, designed to provide near-perfect imagery, at a cost.

Telephoto Lenses

Beyond a normal lens, photographers can find themselves wanting or needing a little more reach this is where telephoto lenses come in handy. Telephotos typically have focal lengths greater than 80mm and can extend to upwards of 400mm, though at that point they are usually referred to as super telephotos.

Short to medium telephotos are the first branches of this category and include the popular 85mm, 100mm, and 135mm options. Each of these lenses has a slightly different perspective, but the longer the focal length, the more compression, shallower depth of field and, obviously, the greater the distance you can be from your subject. Portraiture generally sees the use of these shorter lengths because photographers like to maintain a reasonable working distance to their subjects, since yelling across a field on a windy day isn’t ideal. Also, shorter telephotos are easier to shoot handheld and can be less intimidating, without losing the benefits of shallow depth of field and flatter features.

Standard telephotos and super telephotos are the next level of lens and offer the huge advantage of distance. If you need to capture a faraway subject, like a rare bird or a football player downfield, there is really no other choice. The drawback to these larger lenses is the size and aperture. The longer the focal length, the larger the aperture required, which makes options like an 800mm f/2 lens practically impossible. But, aperture is an important consideration when purchasing a telephoto lens, especially if you are considering the use of teleconverters.

Additional size and weight, coupled with the narrow field of view, make image stabilization an essential feature of telephotos, especially once you exceed a focal length of 200mm. This technology will correct for camera shake, especially since the longer lengths amplify its appearance. Image stabilization is incredibly useful for shooting at slower shutter speeds and low ISOs, by allowing users to capture photographs that would have otherwise been impossible. Additionally, video shooters will greatly benefit from this technology, because it will dramatically smooth out handheld footage.

Wide-Angle Lenses

Sometimes you just can’t fit everything into the frame, whether it’s a group picture or your favorite piece of architecture. Wide-angle lenses, usually found at focal lengths of less than 40mm, fill in this gap with their large angles of view. They work well for landscape and architectural photography, as well as street photography, with the 35mm lens commonly found attached to a photojournalist’s camera.

Options like the 28mm and 35mm will slightly expand your field of view, which makes them critical to some users. Beyond just getting a tad more captured in the frame, wide angles offer a couple of notable benefits, due to their design. One of these is deep depth of field, caused by the shorter focal length. While not ideal for portraits, the ability to capture entire scenes in focus is great for landscapes and architectural photography. Also, photojournalists are afforded more room for focusing errors with split-second shots.

There is one other popular wide-angle category: the fisheye lens. Circular fisheyes cover the widest angles of view, with lenses such as Rokinon’s 8mm f/3.5 HD Fisheye lens. Offering a powerful circular image on a full-frame camera or a 167-degree angle of view with dramatic, exaggerated perspective when used with an APS-C camera, this type of novelty glass is great for infusing an image with some creative distortion and a very distinct look.

Specialty Lenses

The specificity of prime lenses allows them to be used as a high-performing optic with a dedicated purpose. Macro lenses are one type of specialty glass that enable extremely close minimum focusing distances, often with a 1:1 magnification ratio for true-to-life captures. Macros are available in a variety of sizes, from wide to telephoto, though more commonly you will see telephoto options like the AF-S VR Micro-NIKKOR 105mm f/2.8G IF-ED from Nikon. Such focal lengths offer users a good working distance so that you won’t accidentally block light from hitting your subject or scaring away a tiny insect. If still life and product photography, or extreme close-ups of blooming flowers and other natural beauties are subjects of your photographic interest, then a prime macro lens is uniquely suited to help achieve the best image quality possible.

Another type of specialty optic is the tilt-shift lens. These lenses allow you to adjust the relationship between the lens plane and the sensor plane to correct converging lines, reduce perspective distortion, or to achieve more or less depth of field than typically possible. The advantages of these lenses are dramatic, and they offer are the only in-camera way to get movements similar to a large format camera on a DSLR or mirrorless camera body. Image flaws such as keystoning, when shooting upwards at a building, can now be corrected in-camera to avoid the headache sometimes associated with dramatic edits made in Photoshop.

What is your favorite flavor of prime lens? Is there a specific focal length you’d like to try out, but haven’t had the chance to acquire yet? Whatever your fancy, please tell us about it in the Comments section, below.