Polarization can vary greatly depending on the celestial position of the sun, so it is important to understand that both times of the day and the time of the year can impact the amount of polarization one can obtain from a polarizing filter.

Not suggested (unless I missed it), is the use of a tripod! Of course, with landscape work a tripod might be a given! Fiddling with a polarizing filter or any filter can be a disaster without a tripod. BTW: Don’t try to photograph Victoria Falls without a polarizing filter or a tripod!

The only downside here is the gradient sky introduced by the polarizer (you could tell it was early in the morning), but with a couple of simple techniques in software, I can address such problems very easily. Just by using a graduated filter tool in Lightroom, along with a couple of small tweaks, I was able to make my image look even better:

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This chamber conceals a photosensitive surface: a film strip or, in digital cameras, an image sensor. For a camera to produce a legible image, this surface must be protected until it is intentionally exposed. If the camera’s body is not lightproof, we’ll get light leaks or, worse, a completely washed-out frame.

Iris diaphragm levermicroscope

With the sun rising from the left of the frame, it is very clear that the right side of the sky in the image above is where the maximum degree of polarization is, making that particular part of the sky much darker compared to the left. Such situations are commonly encountered when photographing landscapes at the golden hour, so one must be careful when using a polarizing filter, especially when shooting with a wide-angle lens. In some cases, it might be helpful to switch to a telephoto lens and concentrate on a much smaller area of the scene, effectively concealing the uneven sky.

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I didn’t find the ‘Photography Life’ website as early as some other sites, but have been very impressed by both the reviews and articles. However, this and some other articles include “Before” and “After” images. I use Firefox on Windows. If I put the mouse pointer in the central circle, I see one version of the image, with left and right arrows within the circle. If I move the pointer outside the central circle, the image changes to the other version, a [Before] label appears on the left, and an [After] label on the right, in addition to the central left and right arrows. The view is divided down the centre, but consistent each side, and moving the pointer from one half to the other, moving it over the [Before] or [After] labels, or clicking the mouse anywhere, has no effect. I have to rely on the context to decide which is the “Before” image and which the “After”, and sometimes I struggle to decide which is which. Is there an explanation of how to operate ‘Before and After’ images somewhere on the website?

Unfortunately, polarizing filters do come with a set of disadvantages and problems. Here are a few other things you be aware of:

You might also encounter rectangular polarizing filters. The original purpose of rectangular filters was for filter holder use. Such filters are becoming less common since many filter manufacturers have been able to modify their filter holders to accommodate larger, circular filters instead.

Pinhole cameras and camera obscuras use a fixed aperture opening. However, most lenses we encounter today create this opening with an adjustable iris diaphragm mechanism. Similar to the iris in the human eye, the iris in a camera lens expands and contracts to control the amount of light that can pass through. This affects both the brightness of the image and its depth of field.

During the mid-day hours, especially during the time of year when the sun is directly overhead, a polarizer works equally well when pointed at the horizon in any direction, with an even polarizing effect. This makes it easy to get dramatic, dark blue skies against puffy clouds. Also, when converted to B&W, they appear almost black. It can make shooting in otherwise harsh mid-day light more interesting.

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It is very clear that there is a dramatic difference between the two images. Both are “as is, straight out of the camera”, meaning, I did not apply any post-processing to them. The “Before” image is the one I captured before mounting a circular polarizing filter and the “After” image was captured with a polarizing filter attached and rotated to reduce the reflections in the scene.

This article proves you can always learn something new. Thanks! I used a CPL filter for a long time until I discovered that it interferes with auto focus. You mentioned it briefly here but do you have any other suggestions for dealing with that problem?

Aperture refers to the opening through which light can enter the chamber of the camera body. The shutter controls the duration light is allowed to pass through that opening. When exposure is set properly, the shutter will briefly open to let the proper amount of light shine through the aperture to the image sensor. Then, usually in a fraction of a second later, the shutter will close before the image becomes overexposed.

Tom. Nasim wrote that it is the linear version that messes up light meters and auto focus while the circular versions are safe this way. Chances are you have some other issue at play. Also if it happens only in low light situations, the focus sensors may simply not be getting enough light once the CPL exacts its toll.

The only thing you have to watch out when photographing cityscapes is flare, especially if you are using a poor-quality polarizing filter, or if the filter is not very clean. When capturing the below image of Burj Khalifa, I noticed that I had some flare when using my polarizer.

At the same time, we do need to let some light into the camera. Otherwise, we can’t capture any image at all. Thus, we need a way to control how and when light is allowed into this enclosed space. We do this using the shutter and the aperture.

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Just to correct the understanding on how they work. The atmospheric water vapour, water surfaces like ponds etc and reflective surfaces are not ‘scattering’ the light, they are partially polarizing it. Sunlight, and most other light sources are not polarized. They emit light in all directions and angles to the horizontal and vertical. And a ‘normal’ matt surface will scatter light in a random manner leading to just the emittance of the objects detail, whereas, a watery or reflective surface will reflect some of the light in this normal way (so you can see that it’s water), but will also allow some of the light through it and reflect just a portion of light that hit it at a certain angle to the horizontal/vertical plane, hence revealing a reflection of sky / trees etc. The polarizing filter eliminates such ‘plane-polarized’ reflected light, which will be oscillating only in one plane by being able to be aligned in that plane, whilst allowing through most of the light that is ‘normally’ scattered and hence not aligned in just one plane. So it is a bit incorrect to say the problem is ‘randomized’ light, as that is actually what normal light is with regards to polarization, the problem is the polarized light.

Due to the fact that sunlight gets bounced all over the atmosphere and objects present in a landscape, eventually making its way into your camera at specific angles, your landscape photographs might end up looking rather dull and lifeless. Once attached to the front of a lens and rotated to a particular angle, a polarizing filter is capable of cutting out most of the reflected light in a scene, instantly enhancing your photographs by increasing their color saturation and contrast.

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Due to the popularity of DSLR cameras, the demand for linear polarizers plummeted over time, causing filter manufacturers to concentrate on primarily making circular polarizers – from cheap, poorly-coated filters, to high-quality multi-coated circular polarizers with superb light transmission qualities. Although linear polarizers are still available today and work just fine on modern mirrorless cameras, they are not recommended for use due to the unavailability of high-quality options.

When your camera is pointed towards the part of the sky that has the maximum degree of polarization and the circular polarizing filter is at its strongest point, the sky might appear unnaturally dark in images, making it look very fake. In such situations, rotating the filter further and thus reducing the effect of the polarizing filter can take care of the problem, creating not only a brighter sky but also addressing the potential of having a gradient sky in the photograph. Take a look at the two images below:

A larger opening means more light will be able to move through the lens to the camera’s sensor. This means the image will be brighter, but that is not the only impact aperture size has on your image.

Both linear and circular polarizers come in different shapes and forms. The most common shape of a polarizing filter is circular, which is designed to be screwed onto a filter thread of lenses that have them. Circular filters can be used on filter holders, as well as lenses with drop-in filter holders. A circular polarizer is very easy to use. Once it is attached to the front of the lens, it can be rotated either clockwise or counter-clockwise to increase or decrease the effect of polarization.

Lastly, note the difference in the sky – the clouds appear to pop out much more and the sky looks a bit more saturated and darker. This is something you could never replicate in post! The image went from “bland and lifeless”, to “colorful and natural” by simply using a polarizing filter.

Gradient skies can be very difficult to deal with in post-processing, so one must be very careful when using polarizing filters close to sunrise and sunset times, especially when using wide-angle lenses. In many cases, reducing the amount of sky captured in a scene and rotating the polarizing filter to lighten its effect can be effective, as seen below. However, in some cases where re-framing is not desired, it might be better to remove the polarizing filter completely to avoid capturing gradient skies.

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I used the pro “thin” B+W filter you recommend, and it worked very well. I pretty much left it on my lens. However, over time it became very hard to rotate, and the bezel is very thin so getting a good grip could be tricky. A few weeks ago, my lens cap broke the glass somehow, I think because the filter thread area is also extremely thin, making the lens cap more easily push into the filter glass under pressure.

On the other hand, when the sun is closer to the horizon at sunrise and sunset times, the sky will be polarized mostly vertically. This can present problems when photographing landscapes with a wide-angle lens, since the more polarized areas of the sky will be visible in the frame, as shown below:

All camera systems — from the most advanced and the most primitive — rely on a few basic components. The most crucial component is the body of the camera. After all, “camera” literally translates to “chamber” in Latin.

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Just like atmospheric particles randomize light, so do reflective surfaces. Using a polarizing filter can increase color saturation in your images by reducing reflections from water, glass, leaves, and other non-metal surfaces. Additionally, using a polarizing filter helps you create deep blue skies in your images. Blue light waves are shorter than red and green waves, causing them to scatter more easily. Polarizing your view of the sky will prevent randomized blue light from coming into your lens, leaving you with the purest blue light possible.

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There are two types of polarizing filters available on the market today: linear and circular. These types do not refer to the shape of the polarizing filter, but rather to the way lightwaves are modified as they pass through the filter. Linear polarizers have a single polarizing layer and are known to cause mirrors to cross-polarize on SLR and DSLR cameras, resulting in metering and autofocus issues. Circular polarizers (also known as “CPL”), on the other hand, have a second quarter-wave layer that repolarizes the light, which makes it safe to use on any classic or modern digital camera. The only downside of a circular polarizer is reduced light transmission when compared to a linear polarizer.

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The maximum degree of polarization occurs in a circular band 90° from the sun, so it is relatively easy to pinpoint exactly where the sky will appear at its darkest in your photographs. A simple trick is to form a pistol with your index and thumb fingers, then point your index finger straight at the sun. Now rotate your thumb clockwise or counter-clockwise (while keeping your index finger directed at the sun). The parts of the sky where your thumb points towards are going to have the maximum degree of polarization, as they are at the right angle from the sun. This means that when the sun is directly overhead close to the zenith, the sky will be polarized horizontally, making the sky appear more or less even in all directions. Take a look at the below photograph taken at high noon:

Although there is still some haze and softness visible in the image (especially when looking at distant buildings), it would have been an unusable image without a polarizer. I was able to cut down most of the fog and haze in this image.

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Could one use two polarizing filters (first would have to be linear) to have an “adjustable” ND filter? I know a lot of reflections would be lost too so it’s a backup plan if more ND is needed.

For example, an f-number of f/2 tells us that the aperture is equal to our focal length divided by 2. If we are using a 50 mm lens at f/2, the iris diaphragm will open the aperture to a diameter of 50 mm/2, or 25 mm. From this, we can calculate the area of the aperture opening: 490.9 mm^2.

Most lenses use between five and eleven blades in their iris construction. However, you’ll sometimes find vintage and higher-end lenses with higher blade counts. More blades mean that the aperture opening will be smoother and closer to a perfect circle. Fewer blades, on the other hand, produce a more angular polygonal shape. Thus, iris diaphragm mechanisms that use more blades are often considered more desirable since they offer a rounder, smoother bokeh shape.

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A polarizing filter, also known as a “polarizer”, is a photographic filter that is typically used in front of a camera lens in order to reduce reflections, reduce atmospheric haze and increase color saturation in images. It is a popular filter among landscape, cityscape and architecture photographers, although it is commonly used for other types of photography as well.

The vast majority of our planet’s atmosphere is composed of gases that are invisible to the human eye. However, a small portion of the atmosphere is made up of water vapor, pollutants, and other particulate matter. These elements vary in quantity depending on the weather, time of day, and location. Water vapor and pollutants contribute to haze, which decreases visibility over long distances, especially close to bodies of water. The haze we see is a result of light waves hitting particles in the air, causing randomization. Even on a clear, sunny day, distant subjects can be obscured by haze. The best way to cut through that haze is to use a polarizing filter.

Due to my proximity to the Morning Glory hot spring in Yellowstone National Park and lack of an ultra wide-angle lens, I had to shoot a panorama at 24mm focal length, composed of several vertical frames. Once the panorama was stitched in Lightroom, the problem with the polarization in the sky became very apparent. Here, one can clearly see that the center of the sky is where the maximum degree of polarization is – both left and right sides of the frame look much brighter in comparison. This is because the sun was setting on the right side of the frame, which means that the darkest part of the sky would have been vertical, as seen here.

When you adjust the aperture in your camera’s exposure settings, you are changing the size of the opening created by the iris diaphragm. The aperture ring on a lens mechanically adjusts the size of this opening. Turning it moves a lever that spins the iris diaphragm ring. This causes the blades of the iris to expand or contract, which opens or closes the aperture to control the amount of light entering the camera. If the lens doesn’t have an aperture ring, the camera moves the iris diaphragm ring internally according to your aperture settings.

When using a camera with an EVF, I lock the exposure before adjusting the polarizer, else I make sure the EVF auto gain feature is turned off. This allows me to more easily evaluate the polarizing effect. Otherwise, the auto gain feature can make it seem the polarizer is not having any effect.

Nassim has a good photo taken with a polarising filter from a helicopter, but I have had colour bands on photos taken from aircraft windows with a polariser. Apparently this is due to “birefringence”.

The aperture range of a lens determines what focus and exposure effects are possible. However, there is another factor to consider when comparing different lenses. That is iris blade count. This may not seem important, but blade count does influence how defocused points of light — also known as bokeh — appear in your image. Depending on the type of shots you hope to capture, bokeh shape may influence which lens you add to your kit.

If I had not used a circular polarizing filter, it would have taken me a significant amount of time to try to replicate these changes in Photoshop and I am fairly confident that the result would not even come close in comparison.

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Nasim Mansurov is the author and founder of Photography Life, based out of Denver, Colorado. He is recognized as one of the leading educators in the photography industry, conducting workshops, producing educational videos and frequently writing content for Photography Life. You can follow him on Instagram and Facebook. Read more about Nasim here.

Aperture size also affects the depth of field of your image. In other words, it changes how much of your image is in focus. A wider aperture gives you a shallower depth of field, meaning the plane of focus will be thinner and less of your image will be in focus. The opposite is true for a narrower aperture.

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Overall, a polarizing filter is a must-have tool in every photographer’s bag. One of the challenges of being a photographer is making the best of the light you have available to you. Polarizers give you the ability to control the light that comes through your lens, creating vibrant images that might otherwise look dull.

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While the shutter is an important way to control exposure value, cameras rely on an aperture to produce any image at all. Since light rays travel in a straight line, a small enough opening will admit only those light rays that traveled directly through it into a darkened chamber.

One of the main reasons why I personally take a polarizing filter everywhere I go is because I often rely on it to reduce haze in my images. Haze is something we landscape photographers have to deal with very often, so being able to use a polarizing filter in such situations helps quite a bit during post-processing since we can take it one step further and reduce haze even more through various “dehaze” and contrast adjustment tools in the software. Some haze is relatively easy to deal with in post, but when there is a lot of it, a circular polarizing filter can definitely help. Take a look at the below image comparison:

Chris, just put your mouse pointer inside the circle, then left-click-and-hold, then drag the central vertical line – as if it were a curtain – to the left or to the right. Dragging to the left will uncover the left half of the [after] image, while dragging to the right will uncover the right half of the [before] image.

When photographing distant subjects such as mountains, a polarizing filter can also help in reducing atmospheric haze, as explained further down below. So if you are wondering how some photographers manage to get rich colors in their photographs, particularly when it comes to the sky, foliage, and distant subjects, you will find that they often heavily rely on polarizing filters. Although color can certainly be added to photographs in post-processing, the effect of a polarizing filter cannot be fully replicated in software, especially when it comes to reducing reflections and haze in a scene, making the filter indispensable for landscape photography.

As you can see, there are huge differences throughout the image. First, the image with the polarizing filter has significantly less haze in the distant mountains. Second, take a look at the colorful areas of the image: the reds and the yellows appear much more saturated. Note how the evergreens appear completely different, looking greener and lighter in comparison. This is all the result of reduced reflections in the atmosphere and reduced reflections originating from objects in the scene. Without a polarizing filter, the greens appear “dirty”, giving evergreens a much darker and uglier tone.

The same goes for photographing waterfalls and foliage – a polarizing filter in such cases can be invaluable. The below image would have looked vastly different without a polarizing filter:

One of the easiest ways to substantially improve the image quality of your daytime cityscapes is to use a circular polarizing filter. Using a polarizing filter is critical when photographing subjects that are one or more miles away. The longer the distance, the more critical it is to polarize the light you are capturing. For example, this image of Dubai skyline was captured from a vantage point that was over a mile away:

Aside from B+W, there are many polarizing filters on the market today. Most of them are cheaper, but please buy with caution and look at trusted reviews ahead of time. You don’t want to put a cheap piece of glass in front of your expensive lens, only to be later disappointed by the poor image quality and unwanted ghosting and flare. Bad quality filters are not worth wasting your money and time on! It’s better to go without any polarizing filter than to use a bad one.

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A polarizing filter is one of the most essential tools in a photographer’s bag. It is typically the first filter landscape photographers buy to instantly improve their pictures by adding vividness and contrast to them. Putting a polarizing filter on your lens is like wearing a pair of polarized sunglasses over your eyes – the polarized glass blocks random light waves from passing through, creating a clearer image. In this article, we will go through detailed information on polarizing filters, what they do, why they are important, and why you should consider using them for your photography needs.

As you can see from this article, a polarizer is not just something that can help enhance the color of the sky – it is a much more versatile tool that can reduce reflections and haze, and effectively boost both colors and contrast in your images. A polarizing filter is not something you want to leave on your lenses at all times though since it reduces light transmission and it can potentially make the sky look unevenly gradient when using wide-angle lenses. High-quality circular polarizing filters can also be rather expensive to buy and can take some time to get used to. However, those are small disadvantages compared to the benefits they bring.

One of the main reasons why photographers use polarizing filters is to reduce reflections in a scene. Reflections are everywhere around us and they are very common in nature. Aside from common water reflections originating from ponds and lakes, we might be dealing with window reflections or perhaps even tiny reflections of light bouncing off vegetation or rocks surrounding waterfalls. In such situations, using a polarizing filter can help dramatically reduce reflections, even potentially adding contrast and saturation to the image. Take a look at the image below:

As you can see, the pond was reflecting the sky and the trees in the background into my camera. By using a polarizing filter, I was not just able to cut down most of the reflections from the pond, but also reduce the micro reflections coming from the surrounding grass the scene, which changed the appearance and the color of the glass in the resulting photograph. Such effects can never be replicated in post-processing software.

Another potential use of a polarizing filter is when you shoot through the glass of a building or a helicopter. Take a look at the below image:

I captured this image from the Dubai Frame. It was tough to shoot through the thick glass with all kinds of reflections (they use all kinds of LED lights inside), so a polarizing filter was basically a necessity. Once I rotated the filter and cut down most of the reflections, I was able to walk away with another usable image.

Even if you have buildings that are fairly close, a polarizing filter can help reduce haze and improve the clarity of distant buildings and subjects. Take a look at the below image of Hagia Sophia:

I personally use and highly recommend the B+W 77mm High-Transmission MRC-Nano filter, because of its top-notch optics, small footprint, and very minimal light loss of 1-1.5 stops. Although I linked to the 77mm size, make sure to get one that matches your lens.

To make the size of the opening adjustable, the iris in a camera lens uses a series of thin blades arranged in a fan formation. These blades are held in place by the diaphragm. When the diaphragm ring spins, these blades move, changing the size of the aperture and letting in more or less light.

Lastly, some manufacturers might even sell drop-in polarizing filters that are specifically made to fit a particular type of filter holder. The one pictured above allows photographers to easily rotate the polarizing filter using the dial on its top.

This is how a camera obscura, the precursor to our modern camera, can project a scene from outside onto the wall of a dark room. Likewise, the aperture of a pinhole camera is simply a tiny hole in the camera body, often literally punched with a pin in DIY camera projects.

If you’re familiar with the exposure triangle, you’ve likely already experimented with different aperture settings on your camera. Apertures are important tools in any videographer’s arsenal, but what exactly is the aperture and how does it work? Let’s take a closer look at the mechanism that makes the aperture possible — the iris diaphragm.

When I removed it from the lens and looked at it, the filter was quite dirty. After cleaning up the filter and mounting it back on the lens, the flare issues went away.

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Once again, a polarizing filter was necessary to reduce internal reflections and improve the overall contrast of the scene.

I captured the first image with the polarizing filter rotated to yield the maximum polarizing effect, which unnaturally darkened the sky and made it appear uneven. To take care of the problem, all I had to do was rotate the filter until the sky returned to a much brighter state. As you can see, the photograph on the right looks much better in comparison, and with just a single turn, I was able to address the issue without having to remove the filter.

The size of the aperture created by the iris diaphragm is measured in f-stops. Each full stop down reduces the amount of light coming through the aperture by half. The larger the f-number, the smaller the opening and the less light can enter the camera. This is because the f-number is actually a fraction representing the aperture’s diameter.

Of course, you can shoot great video without knowing anything about the iris diaphragm or its function. However, this knowledge does give you an appreciation for the mechanical feats and optical phenomena that make image capture possible. After all, we have the iris diaphragm to thank for our adjustable apertures and the creative control these mechanisms offer.

Now, if we want to decrease the amount of light coming in by one stop, we would need to halve the area of our aperture. That makes the opening 245.45 mm^2. Retracing our steps, we can then find the diameter of our new aperture: 17.7 mm. To find the new f-number, we take our focal length, 50 mm, and divide by the new diameter. This gives us 2.8, the next number on the standard exposure scale.

Many newer lenses have 82mm front threads. Now I wish I had bought the excellent 77mm B&W polarizer Nasim recommends in this size, but when I made the decision 8 years ago, 77mm was about the maximum size needed.

As you can see, Hagia Sophia is relatively close, but the distant hills in the back are quite far, so they looked quite hazy. By using a polarizing filter, I was able to cut down the haze and improve the contrast of the background.

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When photographing waterfalls, you deal with highly reflective rocks, since they have water and other wet vegetation on them, all of which send nasty reflections right into your camera. A polarizing filter makes a huge difference in such situations, not only significantly cutting down on those reflections, but also increasing the overall saturation and contrast of the image.