Craig Lamere – The Lens Choice for Capturing Creative Images
I’m often asked what my go-to lens is. My standard answer might seem like the worst smartass answer ever, but it is the only one I have: My favorite lens is the one that enables me to shoot the image I have in my head. That said, it’s hard choosing the right one. So let’s talk zoom versus prime lenses.
A zoom lens uses specialized mechanics that allow you to change focal lengths by turning the zoom ring. There are as many types and quality of zoom lenses as there are focal lengths. Lenses that are on the lower to midrange end in quality tend to have the greatest zoom margins. Typical zoom lengths at the midrange level include 28mm–300mm and 70mm–300mm. Higher-end lenses typically don’t have the wide range, and are commonly 16mm–35mm, 24mm–70mm and 70mm–200mm.
Prime lenses have a set focal length and do not zoom in or out mechanically. If you are standing in one place and want more or less of an image in the frame, you have to physically move to get what you want in the picture. An 85mm lens has a fixed focal length of 85mm—no more, no less.
Aperture is literally the size of the hole in the lens that allows so much light though it. When talking about aperture, you have to talk about f-stop and depth of field, as they are connected at the hip. The f-stop is the size of the aperture. This is where aperture gets a little confusing for people because the relationship is opposite to the terminology. Remember that the smaller the f-stop number, the larger the aperture. If you are at f1.2, the aperture—or the hole—is much greater than if you were at f16. How all this relates to depth of field is that the aperture determines how much is in focus and how much is not in your image. If you were shooting f1.2, you would have a much smaller depth of field than if you were shooting f16. Depending on the type of shooter you are and the environments you shoot in, this part is critical in choosing the right lens.
Fixed Aperture vs. Variable Aperture
One of the biggest differences between prime and zoom lenses (more so in the lower to midrange zoom market) is how the aperture works in them. Lower to midrange lenses usually have a varying aperture. Variable aperture means that as you change the focal length of the zoom lens, the aperture changes as well. Let’s say have a lens that is 70mm–300mm and f3.5–f5.6. What those numbers are telling you is that at 70mm, your maximum aperture is f3.5, and when you are zoomed out to 300mm, your max is f5.6. These numbers are super-important because they correspond to your depth of field and also to the limitations the lens will have in certain lighting conditions. In the higher-end zoom lenses, you see a lot more of what is called fixed aperture. Fixed aperture is when the lens keeps a constant aperture throughout the entire focal length. For instance, my Canon 24–70 L 2.8 can stay at f2.8 from 24mm to 70mm, which gives me latitude in how I can use the lens. Primes, on the other hand, have fixed apertures because they have a single focal length.
If you are a wedding shooter and you want a zoom so you can easily move in and out of your subjects, the variable versus fixed aperture issue is huge for you. Many wedding locations do not allow any artificial light, and so you are forced to shoot with the available ambient light, and the best aperture you can get to is f3.5; when zoomed to f5.6, even with your ISO pumped up, that may not work at all. A fixed-aperture zoom would better fit your needs. Buying a 70–200mm 2.8 would be a better choice, even though it’s more of an investment than buying the variable zoom.
One of the features that makes primes different from zooms is their max aperture. A lot of prime lenses are somewhere between f1.2 and f2, and most high-end zooms are f2.8 and higher. If you are a wedding shooter whose main concern is having the largest aperture available so lighting issues are minimalized, you would probably choose an 85mm f1.2, 50mm f1.4 or 135mm f2.0.
So which is the better deal? If you are going lens for lens, it would look like buying a prime is the better deal since they typically cost less than a zoom, especially when you get into the higher-end fixed-aperture zooms. But here is one thing you have to take into consideration. When you buy a zoom lens, you are buying focal length X to focal length X, which is basically like having a number of lenses built into one. When you are buying a prime, you are buying only one focal length. To get as many focal lengths as you get in your zoom, you have to buy multiple individual primes, which could cost more than buying one higher-end zoom.
Depth of Field
Depth of field is such a huge part of images and the creative process. I’m not going to get into the nuts and bolts of how it all works, but what I will say is the bigger your lens aperture or smaller the f-stop, the shallower your depth of field will be. It is the shallow DOF that makes more of your background dreamy and creamy, and separates you subject. One other factor to take into consideration is the actual focal length of the lens used. Even though two lenses can be at the same f-stop, they are going to produce very different images based on the focal length in relationship to the subject. As an example, if two people shoot the same person at f.28 and one person is using a 200mm lens and one is using a 24mm lens, the images in regards to depth of field are going to look much different. With the 200mm, you have compressed the image so less of the background can be seen in the frame, and so the DOF seems to be greater in the image. With the 24mm, you have included much more of the background, and so you have not isolated the subject, and your images will not have that creamy, dreamy look. This should be a huge consideration when choosing a lens.
Zoom vs. Prime Trade-offs
Here are a few key points to keep in mind when choosing a lens.
- Convenience: Zooms are going to be way more efficient and convenient if you need multiple focal lengths fast, since it’s like having a number of individual lenses built into one.
- Performance: Primes outperform zooms as far as sharpness and aberrations go because of the simple fact that they have been built to do one thing at one focal length.
- Subtraction and multiplication: If you want to add or take away from a shot, all you have to do is turn a zoom lens one way or another. If you want to add or take away from a shot with a prime, you get to use your “foot zoom” and step closer or farther away from the subject.
- Aperture: Primes have a much greater aperture than a zoom. Most zoom lenses are maxed at f2.8, and primes usually go from 1.2 to 2.0.
- Size: Primes are smaller in size and easier to carry than a zoom.