All About Prime Lenses & Focal Lengths

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.Hi, guys! It's Mandi here to talk to you about how you can affordably improve your photography with the use and understanding of prime lenses. When I first bought a DSLR camera (digital camera with interchangeable lenses) in 2008, I didn't really know what I was doing. My Canon Rebel XTi came with a standard low-quality zoom lens, and because of that, my photos weren't up to the quality I had hoped.

I quickly became a student of digital photography and learned that the lenses you use can dramatically improve your photos, even if your camera isn't baller (and mine wasn't). Back then, I didn't even know the difference between a prime lens and a zoom lens—all I knew is that I didn't want to waste my hard-earned money on the wrong lens. And man, oh man, lenses are expensive, you guys! I searched online for lenses based on reviews and cost, and that's what led me to prime lenses.

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.WHAT ARE PRIME LENSES?

So what are prime lenses? You may be used to zooming in and out with your camera when taking photos, but prime lenses don't zoom—they stay fixed at one focal length. In simple terms, a focal length is the distance between the subject and the "eye" of the camera.

So why buy a lens that doesn't zoom? Well, for one, they are much less expensive than zoom lenses because they have less interchangeable parts. Want a nice lens that will help you shoot in low light and give you beautiful photos with great shallow depth of field?* Well, a zoom lens rarely goes lower than f/2.4, which is a big difference from the f/1.4 of my prime lenses. What's the big deal about the f-number, you ask? The lower the number, the shallower the depth of field and the better your ability to shoot in low light. That's a big deal to me as a photographer. Zoom lenses with nice glass and low f-numbers can easily run way over $1,000. Or you could give up the zoom function for a prime lens for $100-$500, depending on the quality of glass. What a deal, right?

When I was lens shopping all of those years ago, I thought it would be silly not to save money and gain quality by getting a prime lens. I mean, who needs zoom? I can always use my feet too zoom, right? And I could always add more prime lenses in different focal lengths as I got the money. The decision seemed easy. Well, I'll admit—it's a bit more complicated than that.

*In simple terms, depth of field is when your subject is sharp in focus and the rest of the image is blurry.

WHAT LENSES DO I USE, AND WHY?

If you're in the market for a lens upgrade for your DSLR and want the best lens for your money, I highly suggest you consider purchasing a prime lens. I've really enjoyed each of the three prime lenses I've purchased and would love to tell you all about them to help make your shopping decisions easier. Here are the lenses I currently own:

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.CONSIDER YOUR CAMERA TYPE

Your camera type should be the first thing to consider when deciding which prime lens you should get. If you have a lower-end DSLR, it probably has a cropped body, versus the more expensive full-frame cameras. This difference in camera sensor sizes isn't something I knew about when I purchased my first Canon Rebel, which is a cropped-body camera. I was blown away when a friend showed me how a picture taken from the same spot with the same lens as mine looked on his full-frame camera. The comparison made it seem like my lens was zoomed in—but prime lenses don't zoom! His full-frame camera captured so much more! To see this difference for yourself, check out the comparison images above. They were both taken with a 50mm lens from the same spot, but you can see the dramatic difference between the two sensor types.

What does that mean for cropped-body camera users? You should compensate for image cropping by purchasing a lens with a shorter focal length, such as a 28mm or 30mm lens, instead of the 50mm lens that was used in the above images. A 30mm lens would probably end up being the most used lens in your camera bag—a great lens to start out with. But if you want to branch out and expand your lens collection, read about the uses and quirks of each of my prime lenses as I explore their use with different subjects.

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.CONSIDER YOUR TYPICAL SUBJECT MATTER

Another important factor when selecting a prime lens should be your subject matter. What kind of photos do you plan to take? Let's explore each of the subjects I usually shoot and how each lens performs.

Food photographers usually like to get up close and personal with their subject matter, which would make an 85mm focal length ideal (as shown above). This lens appears more zoomed in than the 30mm or 50mm lenses I own, so it's great to get detail shots without having to move in closer to the subject. Of course, you can use a wider angle lens,* but your image will not be the same. Let's discuss the differences below, as shown on a full-frame camera.

*A wide angle lens has a shorter focal length which allows for more content in the frame of the camera, but also results in distortion or light loss/vignetting around the edges of the image.

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.In the above images, you can see how I had to physically move closer or farther away to capture the same image with three different prime lenses. The content of the photo ended up generally the same, but because of the quirks of each lens, we see some differences.

The 30mm lens is so wide that it acts almost like a fish-eye lens, causing dramatic distortion—the foreground of the image is enlarged and the background becomes much smaller. Distortion is more of a concern when shooting up close to a subject. The problem lessens the farther you move from the subject—but we'll discuss that later.

The 50mm lens has less distortion than the 30mm lens, but you can see that compared to the 85mm lens, there is still actually a bit of distortion when shooting so close to a subject. The 85mm allows less of the background in the image (great for food or small-scale product photographers) and no distortion. It's my favorite lens to use in detail shots like this.

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.Portraits can be varied in style, of course, and the lens you use will make a big difference in both the style and the content of your photo. The photos below show basically the same image, taken from the same spot, with three different lenses.

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.

As you can see, the 30mm lens allows more content into the photo. This is great if you'd like to feature a beautiful background or if you'd like to have the person in your portrait be shown from head to toe and don't have much room to physically back away to take the photo. But take note that when using a 30mm lens on a full-frame camera, you will experience vignetting.* The 50mm lens makes for a prettier composition, in my opinion. It takes away less of the background and allows for a more intimate capture of the subject, while still sharing details like what she's wearing or holding. Want to get even more intimate, though? Then the 85mm is your guy. It gets right in there, cutting out most of the background and focusing in on the subject. The 85mm is also a great lens for taking candid portraits at parties. People don't realize you're taking their photo from so far away, so they let their guard down and you can capture their natural smiles and laughter. This is a method I use a lot when photographing wedding receptions.

*Vignetting is also referred to as light loss. It is when the corner edges of the image are darkened because of the presence of the lens wall in your camera's sensor. Vignetting can be somewhat corrected with photo editing software like Photoshop or Lightroom, but even with digital manipulation, you will lose some of the detail in your image.

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.If you're a blogger, chances are you're taking some photos from above. You know the gig—artfully styled sections of citrus for a margarita recipe, or maybe some scattered supplies for a DIY project. The type of lens you need for this kind of shot depends on your sensor type (cropped or full-frame, as we discussed before) and the area of your subject matter.

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.

I usually end up standing on top of my table to take this kind of photo, but with my 30mm lens, I end up with my toes in the photo. I've found that for my purposes, the 50mm lens gets enough in the photo, but if I'm taking an aerial shot and need to get a lot in the frame, I'll switch to the 30mm lens and just watch out for my feet.

I rarely use my 85mm lens in aerial shots, because you just don't get a lot in the frame. But if the subject I'm shooting is on the small side, I might use it to lessen the distortion that you might get with a 30mm or 50mm lens.

 

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.Lifestyle photography varies so much, so really, any lens works great for this kind of subject! It just depends on what you want in the moment or how tight your quarters are. You'll probably resort to a wider angle lens like a 30mm if you're at a restaurant, whereas if you're outside in an open field, you have plenty of space for any lens you want.

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.

Just like with portrait photography, if you want more of the background in your photo, a 30mm lens is great. For more intimate shots, use something more "zoomed in," such as an 85mm lens. In between? Grab a 50mm lens. Choosing a lens for lifestyle photography is pretty simple and depends on what kind of composition you're interested in.

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.Shooting interiors is a little bit tricky. It's difficult for a camera to capture the essence of a room like our human eyes can. When we see photos of homes on blogs, we see only a small portion of the space, because we're limited to the camera's eyes.

Ready to buy a nicer lens for your DSLR, but don't know where to start? This post shares all about prime lenses and how they're an affordable way to achieve higher quality photos.

When I take photos of my home, I usually use both my 30mm and 50mm lenses. The 30mm is helpful to get more of the room in the shot, but it results in some distortion and vignetting, so I prefer to use the 50mm lens if I have space. I rarely ever use my 85mm lens for interior shots, but if you want to capture a vignette, it's a great lens to use because you end up with no distortion.

TRY IT BEFORE YOU BUY IT!

If you're still not sure what kind of lens you need, why not rent one for a fun weekend of photography experimenting? If a friend doesn't have what I'm interested in, I rent equipment from lensrental.com to see how I like something. While I love all of the lenses I've acquired, the one I use the most is my 50mm lens, but back when I had a cropped-body camera, I most frequently used my Canon 28mm f/1.8 lens (may she rest in peace). I lost that lens (GASP—I know.), but it's comparable with the Sigma 30mm lens I purchased to replace it.

If you're interested in even more photography knowledge that I frequently put to use for my projects here at A Beautiful Mess, check out my recent post about using artificial lighting. And if you have any questions about prime lenses, ask them in the comments section below, and I'll do my best to answer them for you! 

-Mandi

Credits // Author and Photography: Mandi Johnson, Photos edited with Spring and Valentine of the Signature Collection.

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