What Does F/1.8 Mean on a Lens?

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When looking into the specifications of a lens, you may be thinking, what does f/1.8 mean on a lens? This number has many benefits when taking pictures, and we’re going to help you understand its value, including how to use the f/1.8 aperture value.

What Does F/1.8 Mean on a Lens?

The value f/1.8 means it’s the maximum aperture of a lens. A lower aperture number, like f/1.8, means the aperture is wide open. If a lens can open its aperture up to f/1.8, it lets in more light for the sensor to boost exposure.

Lens apertures have numbers, yet this isn’t complicated mathematics. This is why we’re going to discuss how aperture works, particularly how f/1.8 affects the performance of lenses, as well as your shooting techniques.

Nikkor f/1.8 lens

Understanding Aperture on a Lens

The f/1.8 value on a lens refers to how wide the lens can open itself to collect light, which is crucial in the exposure and sharpness of your photos.

There are two opposite ends of the aperture spectrum. When you adjust the aperture to f/1.8, this means you’re in the wide-open group of apertures, commonly f/1.2 to f/5.6.

On the other hand, a higher number refers to a smaller aperture or lens opening. This category covers aperture values from f/11 to f/22. These values decrease the amount of light that can reach the camera sensor.

Effects of Using F/1.8 on a Camera Lens

The $22 billion photography industry in the USA covers a plethora of equipment, including lenses. While lenses with f/1.8 values tend to come with higher price points, they also provide several benefits.

  • Well-Exposed Photos: As aperture adjusts to a bigger size such as f/1.8, the lens allows more light to hit the camera sensor. In effect, you can ensure image brightness without using high ISO values. Likewise, this is beneficial when you’re not using a flash or additional lighting systems.
  • Image Sharpness: A wide aperture of f/1.8 creates a shallower depth of field. This value enables you to blur elements in front while keeping the subject in tack focus.
  • Beautiful Bokeh: If you want to try taking pictures with softly blurred light effects, you can do that using the depth of field of an f/1.8 aperture.
  • Speed: Opening the lens up to f/1.8 allows you to use faster shutter speeds, which helps the lens get more light at a faster rate. This is also why a ‘fast lens’ tends to cost more because the aspherical diameter is much larger.
  • Ease of Focusing: Modifying the aperture may also influence the focus shift. Wider apertures like f/1.8 bring in more light, enabling manual and autofocus systems to work faster and more accurately.

Types of Photography That Use F/1.8 Aperture

You can generally use a lens with an f/1.8 value in various kinds of photography, although there are particular niches that would benefit the most from this wide f-stop.  

Hand holding a camera lens
  • Portraits: For flattering portrait shots, using a lens set to f/1.8 provides a shallow depth of field. Whether it’s in a studio or outdoor location, you can blur the background while the subject is in focus.
  • Low-Light: When doing night photography or shooting in low-light environments, you can take advantage of the f/1.8 capacity of a lens to gather as much light as possible to improve exposure. This also applies to interiors and architectural shots.
  • Landscapes: You might use prime or wide-angle lenses when shooting landscapes. These types of lenses usually come with wider maximum apertures to ensure image sharpness from front to back.

Related Questions

Aperture is an essential element in photography, which is why it is a broad topic that’s open for more discussions. So, let’s dive into some of them.

Why Is the Maximum Aperture Important on a Lens?

The maximum aperture is vital in lenses because it affects the result of your photos. The maximum aperture is also the widest, for instance, f/1.8, which you can easily spot on the lens barrel. The maximum aperture may also depend on the focal length.

Is F/1.8 or F/2.2 Better?

There’s not much difference between f/1.8 and f/2.2 as they are both on the broader end of aperture values. However, f/1.8 would be better if you need more light to improve image sharpness and exposure.


Whether you’re taking pictures for work or a hobby, knowing what f/1.8 means on a lens would help improve the final output of your shots. Apply this new knowledge, dedicate time to practice using the f/1.8 value, and you can capture the best-exposed shots.