Prime lenses are designed for exceptional imaging at a single focal length. Unlike zoom lenses that easily span a given focal range and variable field of view with a twist of the zoom ring, the field of view and focal length remains constant. If you want to take in less of the surroundings with a given prime lens, you’ve got to physically move closer, and to take in more of the scene, you’ve got to back up. But of course, as you move, the angle of view remains the same all the while.
It is true that switching to a prime for the first time may take a serious degree of adjustment for many photographers who’ve only worked with zooms, and the flick-of-the-wrist compositional versatility they offer. And it is true the the overall quality of zoom lenses has increased significantly over the past three decades. But there is still something, a certain charm, or a certain shift in the photographer’s eye, when the optic of choice is a single focal length length lens.
Sigma currently offers 22 prime lenses, from a 4.5mm Circular Fisheye through a supertelephoto 800mm F5.6. And whether it’s a DN lens for mirrorless compacts, or DC and DG for APS-C and full-frame DSLRs, every one of these lenses is designed and optimized for exceptional performance at the singular focal length. And of course, the trio of compact DP Merrill cameras, all feature F2.8 prime lenses, paired with the incredible Merrill Generation Foveon sensor.
The individual imaging aesthetics of, say, the circular 180º image of the 4.5mm F2.8 EX DG HSM Fisheye, the life-sized macro detail of the 180mm F2.8 EX DG OS HSM, and the amazing reach of the 500mm F4.5 EX DG HSM are obviously markedly different–but whatever the focal length, the overall prime lens photography experience is similar. When the prime lens is paired with the camera, you’ve got what you’ve got until you change lenses. Want to zoom in or out? That’s what your feet are for!
It can be a bit frustrating at first, and if you hand a camera with a prime attached to most casual photographers, the first question they’ll have is: “where’s the zoom ring!” But with a little patience, practice, and experimentation, the prime lens experience can help you grow visually as a photographer. It can help you recompose your scene, based on the overall angle of attack to the main subjects, distance to subject, most important ground elements, and so on.
You’ll soon find repositioning and relocating yourself to recompose and reframe the scene while keeping the same field of view offers a very cool creative alternative to the casually recomposed zoom. And of course, from a project perspective, there’s a wonderful visual unity in any series of deliberately grouped photos all made with the same prime lens. For example, it might be the warped sense of space offered by a full-frame diagonal fisheye, or the razor-thin depth of field offered by one of our fast F1.4 primes, or a number of similar, but not identical tiny things all captured with the same life-sized magnification of one of our five F2.8 prime macros with 1:1 reproduction that ties a project together.
A good way to test to see if you’ll be comfortable with the prime lens experience is to spend an entire session with one of your zooms locked at a favorite single focal length that’s similar to the prime you’re interested in–can you truly spend an entire photo session at that single focal length? And the next? And the next? If you’ve got more lenses in your bag, treat it like a true prime and swap out to a different zoom lens should you want to mix it up from a focal length perspective.
You may be surprised at how easy it is for you to make the prime lens adjustment in your mind; or you may find that what you really want is a hot new zoom lens that’s got a longer zoom range, or faster constant aperture or such. Either way, there’s a Sigma lens that’s right for you.
With a prime, when you can’t change your location and can’t recompose by zooming, you are forced to really pay attention to every element in the image. If the main subject is small in the frame, overall composition is very important. And if the whole subject cannot fit in the frame, you’ve got to choose what details best tell your story and where to place your edges.
For example, If you’ve got the 85mm F1.4 EX DG HSM lens, and you’re at the edge of a dock, and that docile pelican you’ve been framing for up-close details on the nearest piling suddenly gets spooked and flies twenty feet away to a farther perch, you’ve got to change your overall visual expectations. Same goes with a longer telephoto lens and sports. It is great to have the long, fast, sharp reach of a prime telephoto, but sometimes when the action is coming right at you, you’ll find yourself overlensed. But it’s always best to focus on the shot you’ve nailed with tight framing or excellent composition and not worry too much about the ones you’ve missed!
Is it time for a new prime? Here’s a video explaining the strengths of primes, and constant- and variable-aperture zooms to help you find your next lens!