What is a Fast Lens? Benefits, Drawbacks and Examples
When it comes to photography, having a fast lens can make all the difference in capturing stunning images, particularly in low-light situations. But what exactly is a fast lens, and what are the benefits and drawbacks of using one? In this article, we'll explore the world of fast lenses, including what they are, why they're beneficial, the different types available, examples of fast lenses on the market, and the drawbacks of using them. Whether you're a beginner photographer looking to upgrade your lens collection or a seasoned pro looking to improve your low-light photography, this guide will help you navigate the world of fast lenses and make an informed decision about which one is right for you.
If you want to learn more about lenses, you can read my article on focal length and lens types now.
What is a fast lens?
A fast lens is a lens with a wide maximum aperture, which is typically f/2.8 or wider. The aperture refers to the opening in the lens that allows light to pass through and reach the camera's sensor or film. The wider the aperture, the more light the lens can let in, and the faster the lens is considered to be.
The term "fast" refers to the lens' ability to allow more light to enter the camera, which can help you achieve faster shutter speeds and lower ISO settings. With faster shutter speeds, you can freeze motion and capture sharp images, even in low-light conditions. Lower ISO settings can result in less digital noise or graininess in your photos, which can be especially helpful in low-light situations.
Another benefit of fast lenses is their ability to create a shallow depth of field. Depth of field refers to the area of the image that appears sharp and in focus. A shallow depth of field occurs when only a small portion of the image is in focus, while the rest of the image appears blurry or out of focus. This effect can be used to create beautiful bokeh, or blurred backgrounds, and to isolate your subject from distracting elements in the scene.
Overall, a fast lens can be a valuable tool for photographers, particularly those who shoot in low-light conditions or who want to create images with a shallow depth of field. However, it's imperative to note that fast lenses tend to be more expensive than lenses with smaller maximum apertures, and they can be heavier and bulkier as well. Nonetheless, many photographers consider a fast lens to be a worthwhile investment for its ability to create stunning images with unique effects.
Benefits of fast lenses
Fast lenses are popular among photographers because they offer several benefits. They allow you to shoot in low-light situations without having to use a flash or a high ISO setting, which can result in grainy photos. Fast lenses also allow you to achieve a shallow depth of field, which can create a beautiful bokeh effect and isolate your subject from the background.
Here are some additional details:
Low-light photography: One of the most significant benefits of a fast lens is its ability to capture high-quality images in low-light situations. With a wide aperture, more light can enter the camera, which means you can shoot at faster shutter speeds and lower ISO settings without sacrificing image quality. This can be especially helpful for indoor or night-time photography, where lighting conditions may be less than ideal.
Shallow depth of field: Another major benefit of fast lenses is their ability to create a shallow depth of field. A wide aperture allows you to blur the background, making your subject stand out more. This effect can be especially useful for portrait photography, where you want to draw attention to the subject and create a beautiful bokeh effect.
Versatility: Fast lenses are versatile tools that can be used for a wide range of photography genres, from landscapes and architecture to wildlife and sports. Because of their ability to shoot in low-light conditions and create a shallow depth of field, fast lenses are especially useful for capturing images in challenging situations.
Creative control: With a fast lens, you have more creative control over your images. You can choose the depth of field and blur the background to create a specific mood or effect. This can be especially helpful for photographers who want to tell a story or convey a certain emotion through their images.
Better image quality: Finally, fast lenses often provide better image quality than lenses with smaller maximum apertures. This is because they can capture more light, which results in sharper images with less noise or grain. Additionally, because you can use faster shutter speeds and lower ISO settings, you can capture images with less motion blur and digital noise. This can result in more pleasing images.
Fast lenses offer a range of benefits for photographers, from improved image quality to more creative control. Whether you're a professional or a hobbyist, a fast lens can be a valuable tool in your camera bag.
Types of fast lenses
There are several types of fast lenses, including prime lenses and zoom lenses. Prime lenses have a fixed focal length, which means that they can't zoom in or out. However, they often offer wider maximum apertures than zoom lenses, making them ideal for low-light photography and portrait photography. Zoom lenses, on the other hand, allow you to zoom in and out, but typically have a smaller maximum aperture than prime lenses. Let's explore some of these in more detail below:
Standard fast lenses: These lenses have a focal length of around 50mm and a maximum aperture of f/1.8 or wider. They are often the most affordable type of fast lens and are suitable for a wide range of photography genres, including portraits, street photography, and low-light situations.
Wide-angle fast lenses: These lenses have a focal length wider than 50mm and a maximum aperture of f/2.8 or wider. They are often used for landscape and architectural photography, as well as astrophotography, where a wider aperture can capture more light from the stars.
Telephoto fast lenses: These lenses have a focal length longer than 50mm and a maximum aperture of f/2.8 or wider. They are often used for sports and wildlife photography, where a faster shutter speed is needed to freeze motion. They can also be useful for portraits, as they can create a shallow depth of field and blur the background.
Prime vs. zoom fast lenses: Prime lenses have a fixed focal length and tend to be faster than zoom lenses, which have a variable focal length. Prime fast lenses can have a maximum aperture of f/1.4 or wider, which makes them ideal for low-light situations and creating a shallow depth of field. Zoom fast lenses are more versatile, as they can cover a range of focal lengths, but tend to have a smaller maximum aperture of around f/2.8.
High-end fast lenses: Some of the most expensive and highest-performing lenses on the market are fast lenses. These lenses can have a maximum aperture of f/1.2 or wider and are often used by professional photographers for specialized applications, such as studio portraits or documentary photography in low-light situations.
In summary, there are various types of fast lenses available on the market, each with its own advantages and applications. Choosing the right type of fast lens for your photography needs depends on the genres you shoot, the amount of light available, and your budget.
Examples of fast lenses
Some examples of fast lenses include:
Canon EF 50mm f/1.2L USM: This is a high-end prime lens with a maximum aperture of f/1.2. It is suitable for portrait, wedding, and event photography, as well as low-light situations. It is one of the fastest lenses available for Canon's EF mount.
Nikon AF-S NIKKOR 35mm f/1.8G ED: This is a wide-angle prime lens with a maximum aperture of f/1.8. It is suitable for landscape, street, and documentary photography, as well as low-light situations. It is also relatively affordable compared to other fast lenses.
Sony FE 70-200mm f/2.8 GM II OSS: This is a high-end zoom lens with a maximum aperture of f/2.8. It is suitable for sports, wildlife, and event photography, where a fast shutter speed is needed to capture fast-moving subjects. It is also weather-sealed and has image stabilization built-in. I have this lens and I love it.
Fujifilm XF56mm f/1.2 R: This is a high-end prime lens with a maximum aperture of f/1.2. It is suitable for portrait, fashion, and lifestyle photography, as well as low-light situations. It is one of the fastest lenses available for Fujifilm's X mount.
Sigma 18-35mm f/1.8 DC HSM Art: This is a fast zoom lens with a maximum aperture of f/1.8. It is suitable for landscape, architecture, and documentary photography, as well as low-light situations. It is also relatively affordable compared to other fast zoom lenses.
Panasonic Lumix S PRO 50mm f/1.4: This is a high-end prime lens with a maximum aperture of f/1.4. It is suitable for portrait, wedding, and event photography, as well as low-light situations. It is one of the fastest lenses available for Panasonic's L mount.
There are many examples of fast lenses available on the market, from affordable primes to high-end zooms. Choosing the right fast lens for your photography needs depends on your budget, the genres you shoot, and the amount of light available.
Drawbacks of fast lenses
While fast lenses offer several benefits, they also have some drawbacks. Here are some drawbacks of fast lenses:
Cost: Fast lenses are often more expensive than their slower counterparts. This is because they require more glass elements to achieve a wider aperture, which increases the manufacturing cost. High-end fast lenses can cost thousands of dollars, making them out of reach for many photographers.
Size and weight: Fast lenses are often larger and heavier than their slower counterparts. This is because they require more glass elements and a larger aperture to capture more light. This can make them cumbersome to carry around, particularly if you're traveling or shooting on location.
Shallow depth of field: While a wide aperture can be beneficial in certain situations, such as low-light or portrait photography, it can also create a very shallow depth of field. This means that only a small portion of your image will be in focus. This can be challenging to work with, particularly if you're shooting a group of people or a scene with multiple elements.
Image quality: While fast lenses can produce stunning images, particularly in low-light situations, they can also be prone to certain optical issues, such as chromatic aberration, distortion, and vignetting. This is because they require complex optical designs to achieve a wide aperture, which can sometimes compromise image quality.
Autofocus performance: Fast lenses with wide apertures can sometimes struggle with autofocus performance, particularly in low-light situations. This is because the autofocus system needs to be able to accurately detect the focus point, which can be challenging in low light. Some cameras may also struggle to keep up with the rapid changes in focus as the subject moves.
Fast lenses have several drawbacks that photographers need to consider before investing in one. While they can produce stunning images in certain situations, they are often more expensive, larger, and heavier than slower lenses. They can also create a shallow depth of field and be prone to optical issues, such as chromatic aberration and distortion. Finally, autofocus performance can be a challenge in low-light situations.
In conclusion, fast lenses can be a powerful tool for photographers looking to capture stunning images in low-light situations or achieve a shallow depth of field. They come in a variety of types and range from affordable primes to high-end zooms. However, they also come with their own set of drawbacks, including cost, size and weight, shallow depth of field, optical issues, and autofocus performance. Ultimately, the decision to invest in a fast lens will depend on your photography needs, budget, and shooting style. With the information provided in this guide, we hope you're better equipped to make an informed decision and capture the images you've been dreaming of. Happy shooting!