Prime lens vs zoom, which one to choose then?

Here is a debate that has been going on since the dawn of time, or almost, in photography. I have to admit that there are already many articles on the subject, but I still wanted to give my opinion on the matter and modestly bring my contribution to the debate. So today we’re going to talk about photographic equipment. When you start taking pictures, you often ask yourself this question: should you choose a prime lens (fixed focal length) or a zoom lens?

Let’s be clear from the start of the article, there is no right answer to this question. It’s all a question of choice, of want, and sometimes of preference. So, there will be no truth in itself. The purpose of this article is therefore not to convince you that one is better than the other, but simply to show you the advantages of each of the two possibilities. This is often the case in photography, there are no “black and white” answers. Sometimes you have to step back and judge things as if you were choosing the right camera lens for you.

We always see in forums people getting angry in comments about this topic, some trying to persuade others that using one or the other is better for certain reasons. I hope it doesn’t come to that, but I have to admit it’s a complex subject to deal with. After a little reminder about the notion of focal length in photography, I will illustrate the advantages of using a fixed focal length lens (prime) and also those of using a zoom lens.

Before talking about the subject prime lens Vs zoom, I wanted to recall some basic information about the notion of focal length. Because it is indeed the subject of the article. To know everything about the term, you can refer to the guide I wrote on the subject in “the basics of photography”.

The focal length can be defined as a lens parameter, specified in millimeters, which represents the distance between the sensor of your camera and the optical center of your lens. Yes, when said like that, it sounds scary, but it’s actually very simple. Without going into technical details (you can refer to the article I’m talking about above), the focal length will represent the shooting angle of your scene.

To make it simple, an 18mm focal length will have a larger angle of view than a 50mm, which itself will have a larger angle of view than a 200mm. It’s no more complicated. To come back to the article of the day, you have two types of focal length in photography:

Examples of pictures taken with a zoom (the sunset) and with a wide angle (the wooden bridge)

• Fixed focal lengths/prime lens: this is simply a lens that has only one focal length, for example, 18mm, 28mm, 70mm, 300mm. In concrete terms, you have a shooting angle that always remains the same. To change it, you will have to move,

• Variable focal lengths: alternatively, some camera lenses have variable focal lengths, also known as “zoom lenses”. The lens therefore has two focal length values, a minimum and a maximum, for example: 11-24mm, 24-70mm, 70-200mm. The lens can be a wide-angle, trans-standard or telephoto lens. You can zoom-in and out from where you are and your shooting angle will vary.

Each may have its advantages and disadvantages. Let’s go, I introduce you to all of them below!

Many photographers swear by it, especially the “elders” if I may say so. It’s quite easy to explain this in the sense that until a few years ago, the quality of zooms compared to fixed focal lengths was more than questionable. Many would then prefer to have 2 or 3 fixed focal lengths rather than a poor-quality zoom. Things have evolved since then, though. For now, let’s go back to the advantages of a fixed focal length.

Among photographers, there is a unanimous consensus on this subject. Everybody agrees that fixed focal length lenses are much better quality compared to a zoom lens, as a general rule. It must also be said that the construction of a fixed focal length lens is generally simpler than a zoom lens.

If you like to look at the numbers and tests of lenses, you can have fun comparing several fixed focal lengths and zoom lenses. The tricky thing about comparing lenses is that you are actually comparing something that is not comparable. Let me explain.

In the majority of cases (we’ll get to that below), fixed focal length lenses are brighter, due to a larger aperture, so you’ll actually have a hard time comparing the quality of two different lenses, knowing that you won’t find the equivalent on a zoom lens. For example, take the great Canon 85mm f/1.8 (with a very good price), you can’t compare it to a 70-200 f/2.8, simply because you’ll never have the same aperture on the zoom lens.

This is also often the concern; comparing something that shouldn’t be compared in reality. Some zooms today do as well as a fixed focal length. Note also that even if some fixed focal lengths are of very good optical quality (50mm f/1.8 or 85mm f/1.8), their construction quality (autofocus motorization, materials used, etc.) is far below a classic 70-200mm f/2.8. To have the equivalent quality of construction, it will be necessary to go up in quality and choose a pro range, out of price, for most of us.

One of the big advantages of a fixed focal length lens is obviously the size and weight of the camera bag. Fixed focal lengths will always be lighter than a zoom lens, easier to carry. For travelers, it can certainly make a difference to travel with 2 fixed focal lengths, rather than one zoom lens.

Be careful though (as we’ll see below) because in order to have the fixed focal length equivalent of a zoom lens, it sometimes requires the purchase of 3 or even 4 fixed focal lengths. So in reality, the bulkiness argument is a bit limited.

Again, we’ll have to compare what really is. I often see articles comparing a 50mm f/1.8 to a zoom equivalent, which doesn’t really exist either. But let’s just say that, as a general rule, being easier to build makes fixed focal lengths cheaper.

To make a fair comparison, we should for example compare the price of a 24-70mm f/2.8 zoom lens to several fixed focal lengths, such as: 24mm f/2.8, 35mm f/2, a 50mm f/1.8 and a 85mm f/1.8. Financially, it’s certainly not a winner, but you end up with 4 lenses instead of one.

If there was only one argument to be made in favor of fixed focal lengths, it would be this one. There is no counter argument here, fixed focal lengths are ALWAYS brighter than a zoom, even of excellent quality. There is no zoom that offers maximum apertures at f/1.8, let alone f/1.4. For those who are just starting out, when we talk about brightness, we are referring to the amount of light that can reach the sensor of your camera through your lens. It’s the “aperture” number that you have to look at.

A larger aperture makes it easier to highlight a subject by blurring the background.

The maximum aperture of a lens is written on it as “f/”. The smaller the number displayed (e.g. f/1.4), the brighter the lens will be. You’re going to say, that’s good, but what’s the point? Several advantages:

• Because the aperture is directly related to the shutter speed, you’ll be able to take pictures faster. The difference between the Canon 85mm f/1.8 and the f/1.4 may seem small at first glance, but the difference in aperture allows you to “almost double” the shutter speed. It’s not for nothing that the brighter lens costs 3 to 4 times as much sometimes,
• This means you’ll be able to work under more difficult conditions. I think of all the moments when you lack light: sunrise/sunset, concerts, night photography. The best of zooms will surely get you f/2.8. By having a lens that opens at f/2, you double the shooting speed, with an optic at f/1.4, you quadruple it,
• The possible depth of field will also be shorter. The larger the maximum aperture, the more you will be able to blur your background. You will get more beautiful blurs (bokeh) in the process,

The artistic possibilities related to these three elements (shutter speed, depth of field and conditions) are thus increased and clearly, you will be able to do “more things” with a large aperture.

This is an argument that comes up very often among fans of fixed focal length lenses. I would say that some of the arguments are more or less valid, but you will always find counter-arguments.

Not being able to change the angle of view on a fixed focal length lens (as opposed to zooming in on a zoom lens), should lead the photographer to move around to vary his framing. This has a particular impact on the fact that you have to think about what you’re shooting. With a fixed focal length, it will be necessary to turn around a subject to find the best spot while it is often argued (wrongly or not?) that those who have a zoom move less.

I would say that from my experience, this is even truer if you start, where having a zoom lens will make you stand in the same spot and only “zoom in and out”. With a little more experience, I realize that even with 24-70mm, I tend to move and rotate around the subject to find the best angle or to vary my framing. So, I’d say it’s just up to you here.

One thing though is that having a single focal length makes you think more about your subject and how you’re going to approach it. You don’t have a lot of fun with your zoom, and it’s going to lead to a lot of questions: am I in the right place, can’t I move over there instead, etc.? With a zoom, you will be able to do that, but it is less intuitive and many will just zoom in/out.

Here are the advantages that are often advanced for the use of a zoom.

Let’s say that’s the main advantage of a zoom. Contrary to a fixed focal length, you have here the possibility to not move between where you are and to only be able to change the focal length by zooming and un-zooming. Some people say that this reduces the thinking behind it. It’s arguable, yes and no depending on the circumstances.

During my safari in Tanzania, I used a Canon 70-300 zoom lens, very handy to change the framing when you can’t get out of the car!

Of course, if you spend your time in a specific place without moving, then the zoom is a rather unfavorable choice in this case and clearly it won’t help you to develop your creativity in photography, nor to improve your framing. On the other hand, if you know (like me) how to move around and use your legs, the argument falls a bit short, I think.

As a traveler, where I find the zoom has a clear advantage is that it allows you to be versatile in many situations. The best argument is when you need to change your focal length quickly to take something you didn’t plan on. A silly example, you’re on the edge of a beautiful rice field in the Vietnam, you’re taking pictures with your 70mm zoom already in place (because that’s all you’ve got) and at that moment, a guy on a motorbike carrying chicken cages passes you by. In a fraction of a second, you can change the focal length on your zoom lens and get some detail of this scene. If you were with a fixed 50mm, you couldn’t have. Simply put, a zoom lens allows you to vary your framing quickly enough for these kids of situations.

So, I’m not talking about the discretion of the zoom itself as such, because of course, zooms can be imposing. I remember in S-E Asia with my 70-300mm mounted with its lens hood, I looked a bit like a paparazzi. No, I’m talking about being able to capture some scenes from afar without being spotted. It’s practical in some countries depending on the situation, for example in a market or other. With a fixed focal length, you are usually required to get closer, fixed focal lengths in telephoto lenses are often unaffordable for most people (I think of a 300mm f/2.8 for example).

I think that’s a valid argument as well. Indeed, when you use fixed focal lengths, you’re going to have to change a lot of camera lenses. When you change lenses, you might risk one of your lenses falling out and also getting dust in your sensor. I remember on my safari in Tanzania, I was quite happy to have a zoom lens installed on my camera because of the dust. The few times I changed my focal length to wide angle (for landscape photography), I was still quite afraid that my camera would get filled with dust…

It’s actually pretty silly, but I think it’s kind of the conclusion for the arguments with a zoom. If we add the fact that a zoom is versatile in many situations, we can still say that the price/performance ratio is correct to use a zoom.

So yes, you won’t have the quality of a nice fixed lens with a large aperture, but on the other hand, on recent zooms, the optical quality has greatly improved and you now have very nice quality zoom lenses, like the Canon 70-200mm f/2.8 L IS. On the other hand, the price-performance ratio is there if you put the price on a good quality zoom. I think it’s better to buy 2 quality fixed focal lengths rather than a mediocre zoom somehow.

I’ve come to the end of this article, too long again maybe? Decidedly I have to learn to make it shorter. I think I’ve explained the advantages and disadvantages of using either a prime lens or a zoom lens. Everyone will have their preferences. You’re going to tell me, that’s all well and good, but what should I actually take away from this article?

I would say that no matter what you read on the Internet, you’re always going to find defendants of one system or the other. This proves one thing, that everyone will have their subjective opinion according to the type of photo they want to take, their practice, the places of shooting, in short, the one that suits them the best.

You may read that fixed focal lengths are better for x number of reasons, but in reality, the arguments put forward will be easily criticized by someone who uses zooms. The only arguments I really see for either are the following. Fixed focal lengths will always be brighter compared to zooms and this can clearly impact the types of pictures (and their characteristics) you will be able to take. You’ll have better shutter speed, more beautiful bokeh, and more possibilities in difficult lighting situations. On the other hand, you’ll need to change lenses and have more than one. If you specialize in a particular field (night, concert or landscape photography), an excellent fixed focal length may be the best choice for you.

For zooms lenses, it is versatility that predominates and is the main point. If you need versatile equipment for a variety of situations, such as reporting or traveling, then a zoom lens is probably the best solution for you. Conversely, it will be heavier and less bright than a fixed focal length. That’s what I think is important to remember.

I don’t want to start a debate in the comments, as it is endless, but don’t hesitate to leave me your opinion of the article. Do you see anything that I’ve forgotten? How do you feel about it? In the meantime, I invite you to take a look at how to choose a wide-angle lens?

See you soon,

Sylvain