Using Lens Filters in Photography

Table of Contents

1. Use of Filters
   1. Landscape Photography
2. Types of Filters
   1. Main lens filters
      1. UV Filter
      2. Neutral Density (ND) Filters
         1. Solid ND Filters
         2. Graduated ND Filters
         3. Reverse Graduated ND Filters
         4. Variable ND Filters
      3. Polarizing Filters
      4. Color Lens Filters
      5. Night Photography Filters
      6. Macro Filters
      7. Special Effects Filters
3. Attaching a Lens Filter
   1. Filter Attachment
   2. Filter Adapters
4. How and When To Use Filters
   1. How To Use Filters
   2. When To Use Filters

A very effective way to enhance your photography is to use a camera lens filter. In addition to cameras, lenses, and tripods, lens filters are essential gear for photographers. Landscape photographers especially rely on them.

You can use filters on your lenses to protect them, manage your lighting, change colors, or make specific effects.

Make sure not to confuse lens filters with digital filters that you’d use in Photoshop or Lightroom.

Use of Filters

Most of the time, lenses are covered with lens filters to protect them from scratches or falls. They can also be used to create specific effects, like reducing reflections, eliminating colors, or setting the scene’s light.

Landscape Photography

In natural light photography, where long exposures are used to capture images, lens filters are crucial. With the right filters, you can get results that are difficult to achieve with editing and processing.

With filters in landscape photography, the following can be achieved:

• Control the light: You can control the light by using filters – in most cases, filters reduce the amount of light hitting the sensor. Other times, they polarize the light.
• Manage image color: Manipulate the image’s color using filters that change the hue of the picture so dominant colors show through.
• Lens protection: Guard the camera’s lens against sand, dust, dirt, and water.

Types of Filters

There are a lot of filters that can be used in photography. Here are the main types of camera lens filters:

Main lens filters

• UV  filters: For the most part, they protect lenses from scratches, water, and dust.
• Neutral density filter (ND): A neutral density filter subtracts light depending on its opacity from what hits the sensor. There are different types of neutral density filters based on how the light is subtracted.
• Polarizing filters: The polarizing filters eliminate reflections, and haze, and saturate the colors naturally.
• Color filters: Change how the image looks by adjusting tone and saturation.
• Macro filters: You can take macro shots with macro filters. They work like magnifying glasses.
• Night filters: You can get rid of the light pollution in the scene by using night filters.
• Infrared filters: An infrared filter allows you to simulate the effect of taking infrared pictures.
• Special effects filters: A special effects filter allows you to create effects like “Skylight”, fog, or stars.

UV Filter

UV filters, also called protection filters, are there to protect lenses from dirt, dust, and water damage.

The problem with these types of filters is that they’ll reduce overall image quality by sharpening the image, as well as create side effects like “flares.” Keeping our lenses protected with basic precautions should keep us safe.

Neutral Density (ND) Filters

ND filters (Neutral Density filters) are one of the most essential filters in landscape photography.

The filters reduce the amount of direct light reaching the camera sensor (exposure) but don’t affect the colors or contrast.

Here are the main types of neutral density filters, based on how much light they subtract:

• Solid Neutral Density (ND) filters: A solid Neutral Density filter(ND) subtracts light uniformly throughout.
• Graduated neutral density filters(GND): Gradient neutral density (GND) filters subtract light as a gradient from one side to the other.
• Reverse graduated ND(RGND) filters: A reverse graduated ND (RGND) filter subtracts light in a gradient from the center to the edge.
• Variable neutral density filters: The variable neutral density filter is made up of two polarizers together that, depending on how they’re rotated, can filter more or less light.

Here’s a closer look at Neutral Density filters:

Solid ND Filters

A solid ND filter cuts the same amount of light (exposure value) throughout the filter. Mainly it increases exposure time so you can use a slower shutter speed without affecting ISO or aperture. Almost all of them are glass, so they don’t produce side effects like vignetting.

The filters are classified based on how many stops they reduce (table at right):

The most common ND filters are:

• 3-stop neutral density filter (ND 0.9): Light reduction equivalent to three stops, used when you only need to control a small amount of light.
• 6-stop neutral density filter (ND 1.8): You can block more light, and it’s awesome for sunrises and sunsets when the light’s softer.
• 10-stop neutral density filter (ND 3): Reduce the light a lot. The filter will help with harsh lighting conditions during the daytime and long exposures.

Graduated ND Filters

Gradient ND filters reduce light in a gradient. The filter is cut at one edge by a certain number of light stops (as with uniform ND filters), and the opposite side doesn’t block anything.

Gradient filters can be made from glass, but they’re usually resin, and they’re categorized by the types of gradient they produce:

• Soft-Edge Graduated ND Filter: The degradation of light will be smooth from one edge to the middle of the filter. Ideal for scenes where you’re trying to get rid of just the light in a particular area of the image, like the sky, for instance.
• Hard-Edge Graduated ND Filters: These filters have the same overall effect as soft gradient filters, but they degrade light more pronouncedly. Usually, they are used in images where the light is really contrasty, like seascapes with a lot of sunlight.
• ND Blender filter: In some ways, the Neutral Density Blender filter works like a graduated filter, except it doesn’t degrade light from one edge to the other, but instead from one edge to the other extreme of the filter. Works great in scenes where light reflects in the lower section of the frame, like wet rocks in a coastal scene.

Reverse Graduated ND Filters

A Reverse Graduated ND Filter works the same way as graduated ND filters, except instead of blocking light in a gradient from one edge to the center of the filter, it subtracts light slowly from the center towards the edge.

Most often it’s used in sea photography when the sun’s close to the horizon.

Variable ND Filters

This circular filter has two polarizing filters that block more or less light depending on how it is rotated.

Despite being technically polarizing filters, they belong to the ND filters family since their main function is to block light – usually between two and eight light stops.

This type of filter isn’t very common and is mostly used for videography, although some landscape photographers use it too.

Polarizing Filters

As their name suggests, polarizing filters are used to polarize the light arriving at the sensor so as to achieve the following results:

• Saturate and contrast: The final image should have a pleasing, natural look by controlling saturation and contrast.
• Eliminate glare: Get rid of glare caused by reflective surfaces.

Polarizing filters are categorized into two types: linear and circular, which refers to the way they polarize light, not by their physical shape.

CPL filters (Circular polarizing) are most commonly used today because they polarize the light more uniformly. Remember that light is not always polarized in the same way:

• The optimal point of polarization is obtained when the light source is angled laterally at around 90°.
• These filters will not be useful during sunrises or sunsets when the light falls only on one side very slightly since they will polarize only part of the scene.
• In order to achieve the desired results, you need to rotate the filter until the polarizing effect is uniform.
• It is important to pay attention to the wider angles since it is possible that only parts of the image are polarized.

Side effects are also possible when using the polarizing filter. You can remove things like rainbows and fog from the image that was meant to be included.

Remember that Photoshop can also produce similar effects, such as contrast and saturation, to those created by polarizing filters, with a few exceptions like capturing or eliminating reflections. Consequently, the CPL is essential for landscape photographers.

As my favorite filter for fall photography, I almost always have it on my lens when photographing trees and fall leaves.

Color Lens Filters

By using colored filters, one can modify an image’s hue, saturation, and color.

In the days before digital photography, these filters were very popular, especially with black and white film. They were used to enhance images with certain color undertones.

Nowadays, digital photography and editing have advanced so much that these filters are rarely used.

In the past, gel filters were commonly used to alter the colors of images using their properties.

Night Photography Filters

Night photography filters may sound strange to some, but they exist nonetheless. Most of these devices have been created in recent years to mitigate light pollution and record natural night colors.

In night photography, you can also use the gel filters, mentioned above, to achieve desired colors.

Macro Filters

Despite what you might think, a macro lens is not needed when using a macro lens filter.

Basically, the lens magnifies the image by enlarging it, giving focus to elements otherwise impossible to see otherwise.

Special Effects Filters

In addition to those filters listed above, there are special effects filters:

• Infrared filter
• Skylight filter
• Enhancer filter
• Star filter
• Fog filter

In most cases, these filters are no longer necessary. You can easily achieve similar effects in Photoshop by using editing and processing filters.

Attaching a Lens Filter

Filters can be attached to lenses in many different ways to fulfill desired purposes.

Filter Attachment

A filter is divided into two types based on its shape and method of attachment to lenses:

• Screw-on/Circular: There are round filters that screw on to lenses that are the same dimensions as the lenses they attach to, preventing the need to use additional adapters.
• Square and Rectangular: A square or rectangular-shaped filter is either attached to the lens by means of an adapter ring or by using a filter holder.

Circular Filter	Square Filter
PROS	CONS
Simple to use without a filter holder.	Filter holder is necessary. It may be more difficult to handle at first.
No residual glare after attachment to the lens.	It is possible to capture residual light during long daytime exposures.
Economically priced.	The number of parts involved makes them typically more expensive: larger filters, filter holders, and adapter rings.
Size and weight are smaller.	Larger size and weight.
CONS	PROS
Less flexible when the filter needs to be moved (for example, with graduated).	Better handling of filters, making them more versatile.
Different filters cannot be used at the same time.	Most of them feature two or more filter slots, allowing several filters to be used simultaneously.
Possible side effects include vignetting at the corners.	The vignette in images is usually reduced.

Filter Adapters

You can add a circular filter or square filter to your photography equipment to fit a specific lens with a specific diameter. A circular adapter for circular filters and a square/rectangular adapter ring is needed for using this filter with other lenses.

When buying circular filters, consider getting wider ones and adaptors to fit narrower lenses. By doing so, you won’t need to buy extra filters once you upgrade to wider lenses. (Caution, the other way around, wider lenses and narrower filters won’t work.)

How and When To Use Filters

How To Use Filters

A basic understanding of filters is needed for making the most of your filters in photography.

It is possible for filters to have a counterproductive effect if they are used incorrectly. Among the unintentional side effects are residual glare, flares, and stains.

Here are some basic tips on how to use lens filters:

When To Use Filters

Understanding the different types and uses of filters is essential, but understanding precisely when to use them is even more vital. It is ultimately the light conditions that determine how effective our filters are.

Filters are generally applied in the following situations:

Create a silky water effect: Using a neutral density filter, you can give our images a greater visual impact.

Using a 3 or 6 stops ND filter, for instance, in seascape photography, you can capture more dynamic “motioned” images of waterfalls, rivers, and coasts. Lighting and scene will influence exposure time, but generally between 0.5 and 2 seconds.

Create a softened water effect: By softening the presence of the water with an ND filter, you will be able to shoot more minimalist photos as shown in the previous example.

Capture streaking clouds: Taking long-exposure photos of moving clouds will produce a more minimalist effect and enhance the photograph’s composition.

Filter out reflections from polished surfaces with a polarizing filter: If you want to reduce unwanted reflections in the scene, you can use a polarizing filter.

Remove fog and haze from photographs: In addition to being able to increase the contrast of an image by reducing haze, you can also do this by using a polarizing filter. However, there are other times when your aim can be just the opposite when you wish to capture a more mystical atmosphere.

Increase saturation of an image: You can artificially enhance the saturation of some elements by using polarizing filters. For example, by adding white puffs to a blue sky, you can artificially boost the saturation of the clouds.

Remove people and mobile elements in the image: There is also an interesting result that can be achieved using an ND filter, which is called the “elimination of ghosts.” If you take a long exposure, you can make a location packed with people look as though it was empty. Having people cropped later during processing will save time and effort that would otherwise be used to crop people out.