Another size, the micro four-thirds (MFT) sensor is used by Olympus and Panasonic. Its crop factor is 2x with an aspect ratio of 4 – 3 and is smaller than the APS-C sensor.

Lenses with a focal length between 70 – 150 mm find a niche in macro and portrait photography. Macro lenses allow extreme close-up images. Below, an image of an insect shows the close-up capability of a macro lens.

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Also, you might consider weight. A super telephoto lens may weigh upwards of 10 pounds. It’s like carrying a couple of bricks.

At the far left of the graphic, the 900 mm lens, narrows the angle of view to just three degrees. Focal lengths greater than 300 mm are considered super telephoto lenses.

In general, any lens focal length less than 50 mm is considered a wide angle. More specifically, lenses with a focal length 16-24 mm are wide angle while those from 24-35 mm are standard wide angles. The field of view is wider than what the human eye normally sees, and along with an excellent depth of field, wide angle lenses developed a must-have status for landscape photographers.

Full frame designates a digital camera with a 35 mm image sensor, which measures 36 mm by 24 mm – a ratio of 3 – 2. The terminology stems from the days of analog photography when 35 mm film was a standard format.

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Since photographic optics are expensive, it pays to understand how a particular lens serves your purposes before you purchase. A camera performs only as well as the lens on its front. So understanding the diverse range of focal length lenses goes a long way to helping you achieve your artistic and professional goals.

The zoom lens proves essential for wedding photography and photojournalism where being able to capture the action in the moment is critical. Image quality is a consideration; however, lens manufacturers continually expand and update their product lines. As a result, high-end zoom lenses deliver image quality to rival prime lenses.

A super telephoto lens poses a special challenge for photographers. Just a slight movement of the camera results in large and rapid changes in what you see in the viewfinder – a different experience than using normal lenses. So photographing the erratic movements of a bird in flight or the shifting motion of an athletic event requires a unique skill.

Thanks to a protective layer called the SR booster, premium AR coatings are significantly better at resisting scratches from the trials of day-to-day wear and tear compared to standard AR coatings. Kids, in particular, benefit greatly from the improved scratch resistance on premium AR coatings.

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The focal length of a lens determines the angle of view, also known as the field of view. In other words, it’s how much of a scene the camera’s sensor captures. A shorter focal length, such as that of a 24 mm lens, produces a wide angle of view. The area captured is large while the subject will appear small.

AR coating improves the sharpness and clarity of your vision by defusing light reflections on your lenses. (Image Source)

Some photographers consider a lens with a focal length longer than 70 mm to be a telephoto lens. Others put that number at 100 mm or 135 mm.

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This format utilizes a sensor that mimics the 120 mm film cameras. The sensor size varies with the camera manufacturer, from 43.8×32.9 mm to 53.7×40.2 mm. The aspect ratio is 4 – 3. Fuji, Hasselblad, and Leica produce medium format cameras that are used extensively in advertising and fashion photography.

If you’re simply looking to reduce reflections on your lens and you don’t mind the extra maintenance, the standard AR (+$29) could be just what you need.

If you’re looking for the best in class protection, clearest field of view and the most durable coating, Crizal Sapphire (+$129) is the best option.

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The hydrophobic layer repels water, makes the lenses easier to clean and also helps prevent fogging. This is a great feature for people that are regularly exposed to winter elements such as rain and snow.

Zoom lenses offer versatility to the photographer. Simply rotate the zoom ring to change focal lengths and the corresponding angle of view. Compose and crop photographs in-camera and capture various perspectives.

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In contrast, a long focal length, such as a telephoto lens, results in a narrow angle of view. It captures a smaller area, but the subject appears larger. Furthermore, longer focal lengths compress the image, making the background appear closer and larger than it would with a standard lens.

Understanding focal length helps photographers determine what lenses to invest in and which lens to use on a particular shoot. Focal length describes one of the primary characteristics of a lens. And it plays a critical role in how we execute our creative vision.

Thanks to the advanced multi-layer application process, premium AR coatings have a longer lifespan than standard AR coatings.

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When cleaning lenses with a standard AR coating, rubbing a cloth against the lens creates a static charge that attracts dust particles. Crizal has solved this problem by creating an anti-static property which reverses the static charge every time you wipe your lenses with a microfiber cleaning cloth.

Lenses with standard focal lengths find their niche in travel, street, floral, and portrait photography. It can also be useful for landscape photography. Often called the “nifty fifty,” a quality 50 mm lens excels in multiple photography roles.

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Sometimes called the normal lens, the standard lens focal length measures approximately 50 mm. Some sources refer to any focal length between 35 mm and 85 mm as standard lenses. This lens focal length closely simulates the natural perspective of humans and, coupled with sharp image capability and minimal distortion makes them popular for a variety of photographic genres.

But there’s more. Perspective changes with the short focal length of a wide lens. Objects near the camera appear disproportionately bigger than objects in the distance. A portrait taken with a wide angle lens renders a person’s – or a horse’s – nose unnaturally pronounced.

Lens compression is the visual effect that occurs when using telephoto lenses, making distant objects appear closer than they actually are.

Explore a fascinating comparison of the human eye and the camera, the qualities they share, and the distinctions that make each unique.

Reducing reflections is especially helpful in situations where you have a light source directly hitting your lenses, such as with computer use and night driving.

If you’re looking for a great value, Crizal Alize (+$79) comes with hydrophobic, oleophobic and UV protection at a great price.

A lens with a focal length of 11 mm, shown at the right of the diagram, is an extreme wide angle lens, or fisheye lens. It produces a 180 degree angle of view.

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Crizal was the first AR manufacturer to include UV protection across their entire AR coating line. Their advanced UV protection ensures UV light bounces off the front surface of the lens but allows it to pass through the back surface.

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In this article, we define the focal length and angle of view. In addition, we look at how these factors interact. We also explore the visual characteristics of various focal lengths, the relationship of focal length to depth of field, and how it alters perspective.

With just a couple of lenses, you cover a broad range of different focal lengths. Also, it saves time by not having to change lenses and reduces the possibility of dust landing on the camera sensor.

The crop sensor, called the Advanced Photo System Type-C, or APS-C sensor, has the same 3 – 2 aspect ratio as a full frame but is smaller. It may have a crop factor of 1.5x or 1.6x, depending on the camera manufacturer. Canon uses the 1.6x crop factor, Nikon the 1.5x.

You may take advantage of the distortion in a wider angle lens to achieve a certain look. In another setting, the focal distance of a telephoto lens blurs the background, adding emphasis to the subject.

Meanwhile, the circular fisheye captures its full angle of view both horizontally and vertically. This produces a complete circle within the frame, surrounded by black, as demonstrated in the image below.

Focal length measures the distance between the optical center of a lens – the focal point where the light rays converge – and the image sensor. We measure any given focal length in millimeters, abbreviated mm, with the lens focused to infinity. It is a technical characteristic of the lens, regardless of the manufacturer or camera format, and determines the angle of view.

Check the camera’s specifications page to find details about sensor size, and you’ll be able to determine the effective focal length of any lens.

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Standard AR coating would be just fine for everyone if reflections were the only issue. However, the reality is there are many more elements coming in contact with your lenses than just light.

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Keep in mind that Prevencia has a purple hue, which is quite noticeable compared to Avance and Sapphire. It is suggested that Prevencia be used primarily on computer glasses.

With an AR coating, light hitting the front surface of the lens can pass through instead of bouncing off. Having the back of the lens coated prevents light that’s shining behind you from bouncing off the back of the lens and back into your eye. Having a dual surface coating provides crisp, clear vision in all light conditions.

Some lens focal lengths fulfill specific needs better than others. So, let’s look at the spectrum of focal lengths and how they meet those specific needs. This helps us in finding the right focal length for a particular shoot.

Sensor size determines the equivalent focal length of a lens. A 50 mm lens on a full frame camera performs like a 50 mm lens. A 50 mm lens on a camera with a 1.5x crop factor, such as a Nikon DX camera, equals an equivalent focal length of 75 mm.

Of all the camera lenses, if you were going to work with just one, a standard focal length lens in the range of 50 – 55 mm would be a good choice.

Meanwhile, a zoom lens has a variable focal length. A 70-300 mm lens covers a focal length range from just above the standard lens to just short of super telephoto.

Hi, nice article. There is a small mistake though… crop factor of the micro four-thirds (MFT) sensor is 2x and not1.5x as mentioned…

Overexposure to short wavelength blue light (380-500nm) has been clinically linked to sleep disorders. With the average adult spending over 10 hours a day on digital devices, Crizal Prevencia is a premium AR coating which limits the amount of harmful blue light reaching the eye by 20%.

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The diagonal fisheye captures its full angle of view in the horizontal plane only and fills the entire frame, as shown below.

Both an unwanted artifact and a creative technique, lens flare occurs when light enters the lens, reflects, and scatters. The resulting bright spots or streaks may distract from the main subject. However, photographers often embrace lens flare as a creative element.

In this post, I’ll provide you the insights you need regarding your anti-reflective coating options so you can make an informed decision. There are differences in price, function and features, so we’ll look at those here.

The fixed focal length means a minimum number of moving parts in a prime lens, resulting in sharp focus. In addition, prime lenses allow more light into the camera due to a wider maximum aperture. So photographers can shoot at higher shutter speeds.

Also, we hope to clarify some of the more confusing aspects of this topic when sensor size and crop factor are brought into play. For now, our discussion of focal lengths will be based on a full-frame camera. We’ll get into full frame and crop sensor camera formats in more detail later in this article.

Telephoto lenses produce a shallow depth of field, resulting in a blurred background or bokeh. Also, the longer focal lengths result in lens compression, creating a background that appears closer than it actually is.

These lenses come with short focal lengths in the 8-15 mm range, giving them a wide angle of view, from 100 – 180 degrees. And some specialized fisheye lenses expand that up to 280 degrees.

On a camera with a 1.6x crop factor, such as the Canon EOS M50 Mark II, a lens with a focal length of 50 mm performs like an 80 mm lens.

In addition, ultra wide lenses have scientific applications. For example, photographers capturing polar light rays or recording solar radiation use these lenses.

For blue light protection and durability during those long hours on the computer, Crizal Prevencia (+$159) is the coating for you.

These shorter focal lengths create an extreme bend in the image, sometimes to the point of abstraction. And some photographers exploit this to great effect. Others consider it a novelty. In recent years, the fisheye gained favor with extreme sports photographers, where the distortion due to the short focal lengths adds to the sense of motion.

An increase in focal length to 50 mm drops the angle of view to 46 degrees. Its field of view most closely matches that of the human eye.

Long focal lengths of 300 mm and up rank as super telephoto lenses. These long focal length lenses excel at wildlife and sports photography.

Working with an interchangeable lens camera, a variety of quality prime lenses enables you to deliver a quality product in diverse settings. If a quick reaction is important, a zoom lens empowers a photographer to adapt to the proper focal length in an instant. And for a general walk-around camera lens, the 50 mm is a favorite among photographers.

As a photographer, it’s not absolutely essential to know the technical details of focal length and field of view. However, knowing how a particular lens renders the subject helps in achieving your creative vision.

Wide angle lenses also introduce some distortion. Parallel lines converge due to the wider angle. Photographers find creative ways to make use of this distortion.

At the most basic level, all AR coatings defuse light reflections on the front and back surface of the lens. The coatings allow more light to pass through and improve your visual acuity.

Lens vignetting is a gradual darkening of an image at the edges; it is often an issue to be corrected but sometimes used as a creative touch.

Heat distortion in photography causes blurring or shimmering effect in images, due to temperature variations in hot environments.

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When you order prescription glasses, you’ll make some additional choices regarding upgrades and options. The purpose of most lens upgrades are self-explanatory, but selecting an anti-reflective (AR) coating isn’t always an easy choice to make due to the variety.

As much as we try, we end up touching our glasses many times throughout the day and in the process we leave fingerprints and smudges behind. An advanced oleophobic layer on premium AR coatings makes it easy to wipe away oils from fingerprints and eyelashes.

Combining longer focal length with good image quality commands high prices. A 600 mm lens for the Nikon Z series cameras sells for around $15,000 (US).

When it comes to image quality, prime lenses are superior. A prime lens contains fewer optical elements, reducing the chances of anomalies like chromatic aberration, vignetting, and distortion.

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A telephoto lens becomes essential when you want to get close to a subject from a distance and to get physically close is either dangerous or socially impolite.

Standard AR coatings, though they can do a good job of reducing reflections, still have a noticeable greenish hue. Premium AR, like the Crizal Sapphire, has advanced to the point where the AR layer itself is virtually colorless. The coating not only diminishes reflections on your lens, but also eliminates the greenish light flares that can be present on standard AR coatings.

A 28 mm wide angle lens with its short focal length produces an angle of view of 74 degrees. These lenses are generally deployed for landscape photography.