What is a prime lens and what are they used for?

Hey folks, if you’re new to photography, you’ve probably heard the term, “prime lens” thrown around quite a bit, but what exactly is a prime lens and what are they used for?

In this article, we’ll be doing a deep dive into what a prime lens is, what they’re used for, the pros/cons versus zoom lenses, and, finally, how to choose the right one.

Let’s jump in!

sony camera with prime lens
So, let’s talk about prime lenses!

What is a prime lens?

Alright, so, starting off, what is a prime lens? What does “prime” mean, in this case?

A prime lens is just a lens with a fixed focal length. What this means is it simply cannot zoom or, in other words, that the lens is locked into one focal length.

Prime lenses have been around since the dawn of photography. They come in many shapes and sizes and, despite being a rather simple concept in theory, they’ve still been improving constantly over the years along with all other photography gear.

Disadvantages of Prime Lenses

Before we get too deep, it’s important to first cover the disadvantages of prime lenses.

Fixed Focal Length

The only real disadvantage of a prime lens is that, indeed, it is a fixed focal length. This can be a problem for those used to versatile zoom lenses.

The downsides of a fixed focal length are as follows: having to “zoom” with your feet and having to switch lenses more often.

Can’t Zoom

With a prime, you can’t zoom in and out. Thus, you have to do what many photographers call, “zooming with your feet”. This is just a figure of speech that means, “walk closer to or further away from your subject”.

After using primes for a while, you get used to it. However, if you’ve switched from a zoom lens, it can be annoying.

Switching Lenses Often

The other main disadvantage of prime lenses is that you’ll need to switch lenses often if you want to shoot anything outside of the focal length you currently have on.

For example, if you’re using an 85mm prime to shoot portraits, you’d have to switch to a wide-angle lens if you wanted to capture, say, a large building.

With that being said, some photographers will choose a versatile focal length (something like 35 or 50mm) and never swap out their lenses.

Why should I use a prime lens?

Alright, so we covered the disadvantages of a prime lens, but what about the advantages? What makes prime lenses so great and what are they used for?

Better Optical Quality

There are a lot of reasons to use a prime lens, but the biggest is that the optical quality is simply better than zoom lenses. If you take a prime lens and compare it to a zoom lens in a competition of sharpness, the prime lens will win pretty much every time without fail (there are, of course, exceptions to this rule).

This is primarily due to the fact that prime lenses don’t suffer from as much diffraction (or other optical anomalies) as they don’t have as many glass elements as a zoom lens. And those glass elements, given that the focal length stays unchanged, don’t need to be constantly moving and shifting like in a zoom lens.

Additionally, prime lenses, once again thanks to their simplistic construction, offer wider apertures, which allows for better depth of field (bokeh/background blur) and greater low-light performance.

Smaller Size & Weight

Another big advantage is size. Prime lenses are almost always smaller than zoom lenses. This is due to the same point above, there’s simply less stuff that needs to go into a prime lens since it’s so much more simple. There are less moving parts, and not as much glass (or for that matter, metal or plastic) is needed to make things work.

While some photographers may not mind lugging around a huge setup, I personally am much more likely to actually take my camera out and practice if I don’t have to lug around a massive and heavy lens.

Size comparison between a zoom lens and a prime lens.
Size comparison of a typical zoom vs prime lens.

Usually Cheaper

The next pro is that prime lenses are oftentimes much cheaper than their comparable zoom counterparts.

While some photographers may, once again, be unconcerned about cost, a prime lens can offer incredible value to those photographers who either can’t or don’t want to spend an exorbitant amount of gear.

Just to throw an example out there, the Sigma 30mm F1.4 costs about half as much as the Sigma 18-50mm F2.8. Despite being substantially cheaper, the prime (30mm F1.4) offers better sharpness and smaller size.

Perfect for Learning

Finally, prime lenses are just good to learn on. As I mentioned earlier, there’s an old photography saying that goes, “zoom with your feet instead of your lens”.

When using a zoom lens, it’s all-to-easy to get lazy with composition and, instead of moving to a better spot, you’ll just end up zooming in your lens and getting a picture that’s just not as great as it could be.

When I first started photography, I started with the standard kit zoom lens. I don’t feel as if I started to get a real grasp on composition until I picked up my first 50mm prime lens.

Heck, even after almost a decade of photography practice, I still feel as if a prime lens gets my creative juices flowing way better than a zoom. There’s something about having that artificial limitation that makes me think more about my shots.

Massive collection of Sony lenses. Photo Credit: Sony Alpha Universe
Sony, along with third-party manufacturers, sells a LOT of different lenses (and this picture is outdated!).

So what prime lens should I choose?

Alright, so now that you know the pros and cons of prime lenses, what focal length should you choose?

This is a question that greatly comes down to what you like to photograph. Remember, you cannot zoom with a prime, which means you are one hundred percent locked into what you’re shooting with.

Below, I’ll cover a few different focal lengths along with my suggested lenses (full reviews included). These suggestions are tailored to Sony users, but the general advice is useful no matter what brand of camera you shoot with.


Are you primarily interested in capturing wide-open landscapes and other grandiose scenes? Do busy and complex cityscapes interest you more than intimate, close-up portraits?

In that case, shop around for a wide lens. For Sony APS-C shooters, I’d recommend the Rokinon 12mm F2.0. For full-frame photographers, consider the budget-friendly Samyang 14mm.


Want to get all the benefits of a prime lens but still have a little bit of versatility? Planning on capturing a little bit of everything but never want to have to switch lenses?

Consider picking up a mid-range, catch-all prime. For a6k series users, I’d highly suggest the Sigma 30mm F1.4 (one of my favorites). For full-frame users, grab the fabulous Sigma 35mm F2.0.


Want to capture more detail? Does taking portraits of beautiful people or detailed photos of everyday objects appeal to you?

If so, grab a telephoto prime. For APS-C shooters, it’s hard to go wrong with the Sigma 56mm F1.4 (see a trend here? Sigma rocks!). For full-frame users, consider something like the budget-friendly Viltrox 85mm F1.8.

holding a prime lens
No matter what kind of photos you’re trying to create, a prime lens can do the job.


Of course, there are prime lenses for everyone. Some photographers prefer wide, some prefer mid-range, and some prefer ultra-telephoto. There’s no right or wrong answer.

At the end of the day, choosing a prime lens over a zoom does have some sacrifices, but for many photographers, the cons are well worth the pros.

So, what are you waiting for? Go pick up a prime lens and start practicing. Thanks for reading. 🙂

Looking to learn more about photography basics? Check out our guides on crop vs full frame and how to take sharper photos.

The reviews listed above contain some affiliate links, which means that if you purchase a lens through one of my articles, I get a very small commission at no additional cost to you. Thank you. <3