Photography Glossary

What is a Zoom Lens?

March 20, 2023 by

This is a guide covering everything you need to know about zoom lenses.

Maybe you are in the market for one or perhaps you already bought one but are not sure what to use it for.

In either case, we’ve got you covered.

Table of Contents

What is a Zoom Lens?

The zoom lens is a type of camera lens that has the ability to take images at a range of focal lengths. They are a competent type of lens, able to “zoom” in and out based on the photographer’s needs.

The focal length is directly related to the camera’s angle of view.

The lesser focal length millimeters (mm) a lens has, the wider the angle of view becomes. The longer the focal length is, the narrower it gets.

The zoom lens allows photographers to adjust their focal lengths on the fly. At this point, the lens essentially becomes a 3 or 4-in-one lens.

Photographers can go as wide (zoom out) or narrower (zoom in) as they please.

zoom lens example
zoom lens

What is a Zoom Lens Used For?

Well, the zoom lens can certainly be used for many purposes. Zoom lens photography can be easily implemented by anyone, regardless of their experience and photography niche.

Zoom lenses have multiple focal lengths, some ranging from the widest settings to the narrowest fit. It will surely cost you a fortune since the lens is very multipurpose and can be used in landscape and shooting subjects far away.

You can get the most out of your zoom lens if you use them in bright conditions.

The lens doesn’t have the fastest aperture available on the market, even the quickest zoom lens is quite rare (because it’s crazy expensive).

Despite the ability to virtually shoot everything in almost every condition, zoom lenses are often connected with traveling.

Street photography, photo journaling, and zoom lenses are always used in situations where you don’t want to fuss about changing lenses every 3 shots.

Videographers also find the zoom lens to be particularly useful since there is no need to change focal lengths during the shooting.

Videographers will just need to zoom in once the subject is moving away from the lens or zoom out to capture more surrounding details.

To recap, zoom lens uses are limitless.

What is Considered a Zoom Lens?

A lens that can change to a range of focal lengths is considered a zoom lens. There are various types of zoom lenses with their own unique characteristics and uses.

You can find your zoom lens focal range with its max aperture on the front and base of the lens. A lens with “18-140mm f/3.5” means that the camera has an 18-140 focal length range with a maximum aperture of f/3.5.

Let us get into the two categories that classify types of zoom lenses:

1. Fast and Slow Lens

The fast lens normally has a low f-stop as its maximum aperture.

A fast lens is wider and allows more light to hit the sensors in the camera, resulting in brighter images.

The name “fast lens” came from its ability to let photographers use faster shutter speeds. In comparison, the slow lens commonly has maximum apertures larger than f/4.

fast shutter speed

It lets less light enter the sensor, this forces the photographer to use slower shutter speeds. Hence the name, “slow lens.”

Constant and Variable Apertures

Lenses either have a constant (fixed) or variable aperture. You can easily check this by looking at its marking.

An example of a constant aperture lens will probably be 70-200mm f/2.8.

The markings explain that throughout the changes in focal length (70-200mm) the aperture will stay at f/2.8.

This technology is quite rare and will usually cost you a fortune.

On the other hand, the aperture of zoom lenses that have variable apertures will constantly change.

For example, let’s say that your zoom lens has a marking of 55-200mm 1:4-5.6G.
The aperture of f/4 corresponds to the maximum aperture at the smallest focal length, which in this case is 55mm.

The aperture of f/5.6 is linked to the maximum aperture at the largest focal length (200mm).

Basically, the more you zoom in, the progressively slower your aperture becomes. This will decrease the amount of light hitting the digital sensors.

2. Focal Length

Zoom lenses are capable of covering several focal lengths within a single lens.

There are wide-angle zooms (10mm-24mm), telephoto zooms, and some special zoom lenses that cover wide-angle to telephoto (18-140mm).

Here is a more detailed categorization of them:


These types of lenses are targeted primarily at landscape photographers.

They have short focal lengths, usually 35mm or shorter.

However, if the focal length is shorter than 24mm the lens will be classified as ultra-wide, a greater option for landscape photographers.


The normal focal length is around 50mm.

Photographers will often use the standard lens to shoot street, candid, and portrait shots.

Telephoto Lens:

Usually, the telephoto lens covers a small portion of a shot/scene. These types of lenses are often used to take flattering photos of subjects or scenes that are far away.

The lens is often used in wildlife and sports photography.

Photographers still debate about when the telephoto lens starts and ends. I’d say that telephoto lenses start at focal lengths above 85mm and end around the 135mm mark.

Do You Need a Zoom Lens?

I wouldn’t go that far to say a zoom lens is a must-have in your arsenal. I personally think it is a worthwhile investment for certain situations.

Don’t get me wrong, the zoom lens is certainly very useful indeed. Unfortunately, they don’t produce the sharpest images. Prime lenses certainly do a better job than them at capturing a tack-sharp photo.

They sure are useful for beginners that still need to learn the basics and experiment around with various focal lengths.

They will also come in handy if your field of photography requires a lot of commuting since it’s lighter than bringing 4 prime lenses.

A zoom lens will also aid you better in situations where you’re moving is limited, or when your subject is just too far away. Shooting in tight spaces that limits your movements will be easier when using zoom lenses.

In the end, it all depends on your niche in photography.

Is Prime Lens Better than a Zoom Lens?

Well, you can’t really say a definite yes or no in this debate.

Both lenses have their own specific uses and purposes in mind when created.

The prime lens was made as to a super sharp lens at the expense of its price, weight, versatility, and simplicity.

In comparison, bringing a high-end zoom lens is like bringing multiple prime lenses since you can just change the focal length in a heartbeat.

The main advantage that a zoom lens has is its ability to change focal length without changing lenses. If you use a prime lens, you become subject to constant lens changing while also carrying your multiple prime lenses with you.

Since you can just use one zoom lens in multiple situations, you can travel lighter. Traveling light is a blessing for photographers that are going on a trip, especially if you are in a run-n’ gun situation.

But there are also disadvantages that should be taken into consideration.

A zoom lens isn’t quite sharp as the prime lens and is unfavorable for shooting in a low-light situation because of the slow aperture they have.

A slower aperture prevents light from entering the camera.

To counteract this, it is suggested to lower your shutter speed or just buy (the expensive) fast zoom lens.

The slower shutter makes your image more prone to motion blur, make sure to bring a tripod and a remote shutter release to prevent it.

What is the Difference between a Telephoto Lens and Zoom Lens?

Zoom lenses are essentially lenses that can change their focal length. Your field of view becomes narrower/wider with every twist/press of a button. A narrow field of view will make the object appear larger and vice versa.

A telephoto lens is commonly referred to as a lens that has a long focal length.

A zoom lens will have two focal lengths, often inscribed on the lens, i.e. 18-140mm. This means that the zoom lens can change the focal length from a wide-angle into a telephoto zoom.

The non-zoom variant or a fixed focal length telephoto lens will only have one focal length. A moderate telephoto will start from 135mm and above.

We will then peek into the purpose of using the telephoto lens. A telephoto lens is ample for every situation that involves a subject far away from you that cannot or should not be approached (safety and practicality issues).

The telephoto lens increases the focal length, previewing far away objects with a high level of detail that is usually only found in close-range photography.

They are also significantly sharper than their zoom counterparts.

However, the telephoto lens is fixed at a single focal length and isn’t versatile. This is where the zoom lens excels, since it can freely morph its focal length at will.

What are Some of the Most Popular Zoom Lenses?

So, are you interested in purchasing a new zoom lens to add to your arsenal of lenses? Here are some of my recommended zoom lenses for both Canon and Nikon shooters:

  1. Sigma 24-35mm f/2 Art
  2. Canon 100-400mm f/4.5-5.6L IS II
  3. Canon 24-70mm f/2.8 L II
  4. Canon 70-200mm f/2.8 L IS III
  5. Nikon Z 24-70mm f/2.8 S
  6. Nikon Z DX 16-50mm f/3.5-6.3 VR

These lenses aren’t listed in any order, not a ranking list, they’re just my favorites. Before you visit amazon or the closest lens provider, there are a few things that you need to consider.

1. Max Aperture

Aperture will determine the amount of light that will hit your camera’s sensor, affecting its performance in low and high light conditions.

The faster/larger your aperture is, the easier it will be to shoot in low light.

You can also manipulate the shutter speed to either compensate for the slower apertures or to capture fast-moving objects. Use it however you see fit.

2. Stabilization

You’ll feel your camera shake, even more, when you zoom further in.

Some lenses will have built-in stabilization, while others are better off using tripods at extremely long focal lengths.

Depending on your shooting style, the stabilization will have a big impact on your image and bank account.

3. Sensor Size

Your camera’s size will impact the lens that you are able to use.

Not all are created equal, some sensor types are just not compatible.

The APS-C sensor will have an “adding” effect to your zoom. This makes you feel that you’re getting more reach using a crop sensor camera, despite the image having less angle of view.

4. Size & Weight

Zoom lenses will vary in size and weight, even if they have the same focal range. Luckily, some of the zooms are light.

Unfortunately, the vast majority of them are significantly heavier. Longer lenses will always weigh more.

Final Remarks

A zoom lens is basically a lens that can change its focal length based on its range.

Zoom lens photography is often looked down upon since it’s incapable of producing images as sharp as its prime counterparts. But behind that single weakness, lies the strength of the zoom lens in its versatility and simplicity.

Prime may suit your taste better since it can shoot sharper images, but the zoom lens offers a lot of its flexibility. Choosing only one is surely a hard choice indeed, even I would doubt choosing a zoom lens as my ONLY lens.

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