Photographing Waterfalls: An Intermediate guide: Photographic Filters

The key to a successful waterfall photograph is to control the light that reaches your camera's lens. To gain excellent control over the light you must master the use of photographic filters. There are many types of photographic filters, many of which are now considered obsolete for digital cameras, but a choice few are essential tools for both the enthusiast and the professional photographer.

Cameras
In order to use filters, you must be using a camera that can accept them. SLR-type cameras can except filters directly on the lens. SLR lenses have threaded ends were a circular photographic filter can be screwed on. Since one may have many lenses of different sizes and shapes for their SLR camera, they may also require different size filters…if they plan on using them with each lens.

A standard screw-on barrel filter

A typical filter is thin and circular with threaded edges. Most have threads on both ends and can be stacked.

Most compact or “pro-sumer” cameras, the ones without interchangeable lenses, but have manual controls, have the ability for attachable filters. For many of these cameras, you will have to buy a lens tube filter attachment, which screws on over the lens barrel and allows you to attach filters over the lens. Filter tubes generally cost between $15 and $25 and can sometimes be left on the camera as an extra layer of protection for the lens barrel.

A Raynox Lens Adapter Tube

Raynox is a manufacturer that produces all sorts of lens tube adapters for many fixed lens (pro-sumer) compact cameras.

Less, feature-rich compact pocket cameras usually don't allow or filters to be attached. If your camera cannot except screw on lens filters, there are kits available consisting of an attachment for your tripod or tripod mount and a filter holder that will hold square filters in front of your camera lens. These kits are generally more expensive, but very versatile and interchangeable between different cameras and lenses. Cokin also makes a filter holder that will attach to a compact camera with a magnet, allowing for great flexibility and quick removal.

A Cokin universal filter holder

A universal filter holder from Cokin screws onto the tripod socket and allows for drop-in filters to be used with various models of compact cameras.

Photographic filters can cost anywhere between 10 and $300. Generally the more you spend, the higher-quality glass and higher-quality coating will get. It is recommended when you buy a photographic filter that you get one that has multiple layers of coatings. Multiple coatings will reduce the amount of reflections and ensure better contrast and more accurate color.

It's also recommended that you stick with brand names. Some notable and reliable brands for photographic filters are Hoya, Tiffen, B+W, Cokin and Heliopan. You can also stick to the same brand filter is your camera manufacturer, if available.

There are many filters available that will change the color of the light reaching your camera lens. Warming filters will allow for more orange, while cooling filters will let in more blue light than other colors. It is not recommended, if you shoot in digital, to invest in these types of filters, as these types of color changes can easily be done in Photoshop or any other image editing program. The type of filters you should invest in are the ones that change the characteristics of light that enter the lens, not the color.

Cleaning your filters
Great care should be taken when cleaning your filters and camera lens. You should have the following:

a blower brush
lens cleaning solution
microfiber cloth
patience

A blower brush for lens cleaning

A blower brush will help remove particulates from the lens or filter, which is usually all it takes to prep the glass. Most camera shops, electronic stores and even office supply stores will carry a 3-pack of the brush, cloth and fluid for a reasonable price.

To clean a lens, the first thing you should do is use the blower brush to remove any particulates adhering to the glass. Being gentle is the key. It's the particulates that will scratch your lens if you press too hard. Move the glass around in the light to check to see if there anymore particles or smudges on your lens. Particles should be removed with the blower brush. The smudges will require some cleaning solution and a good buffing with a microfiber cloth.

Add a few drops of cleaning solution, such as Formula MC, to a small, clean area of your microfiber cloth. Apply gently to the glass surface area using side to side motions. Then use a dry section of the microfiber claw to buff a way the cleaning solution. Be careful not to press too hard. It is not recommended applying cleaning solution directly to the lens or filter, as it may seep through a seam and cause damage. It is also not recommended use glass cleaning solution, such as Windex, as it may damage the special coating on your glass. Always check your cleaning job, by moving the glass around in the light, to see if you got it all.

Types of filters

The UV protective filter
The packaging for a UV filter will tell you that by blocking ultraviolet rays from your camera sensor, you will reduce the haze and improve overall contrast of your photographs. I doubt this is true. If UV light was that damaging to photographic quality, all quality photographic glass, including the lens on your camera, would already come pre-coated to block UV rays, and you wouldn't even need a UV protective filter. Even so, I highly recommend buying a UV protective filter. Why? For the protection… the physical protection. UV filters are so inexpensive; I recommend you leave it on your camera at all times to shield the more expensive lens of your camera. A high quality UV filter will run you about $25, while replacing a damaged lens could be 20 times more that amount. So with a UV filter can you rest assured that you have an extra layer protection on your very expensive lens.

Polarizing filters
A polarizing filter is a must-have for an outdoor photographer. You will get results from a polarizer that you will not be able to replicate in the digital laboratory, even if you are a Photoshop expert.
There are two types of polarizing filters: Circular and Linear. Circular seems to be the most widely available and versatile. It's the only one I recommend. What a circular polarizer will do for you is:

In a nutshell, a polarizing filter reduces glare. Just like polarized sunglasses. It counters the effects of strong sunlight, reducing glare from just about everything; from water to the sky. When you get rid of glare you improve the contrast and saturation of your scene.

Sounds great, doesn't it? So if a polarizing filter is so great, why aren't all camera lenses polarized? While there are some disadvantages. Polarizing filters tend to darken the scene, allowing less light to enter the lens, which means to take action shots, you need to use a higher ISO speed (thus introducing noise). They are also made of two layers of glass. One stationary layer, and one that is rotated. Two additional layers of glass can reduce the quality of a lens, increasing reflections, distortion and vignetting. A higher-quality polarizer can reduce those effects, but will add a significant cost to the camera.


The wet surface of the moss-covered shale at Bucktail Falls produces reflections or glare that make the image look harsh.	A circular polarizer virtually eliminates the glare, makes the image more calm, easier to expose, and increases the saturation in the moss.

Using a polarizer filter is fairly easy. Rotating the outer ring will align the crystals of one layer of glass with the other. When the crystals are aligned properly, you will see the glare in the scene greatly reduced. To more clearly see this reduction .your camera towards the sky or a wet surface with reflections. The sky will become a dark blue, and a wet surface will darken as the reflections disappear.

When using a polarizer filter, it is important to keep in mind that the effect is most prominent when the scene you were photographing is positioned 90° from the sun. The effect will not be noticeable at all when photographing into or with the sun behind you.

If you're using a wide angle lens, the scene you are photographing may have portions that are 90° from the position of the sun and some that aren't. Which gives a gradient effect of darkening across the sky. Some photographers do not prefer this effect, but since most skies do not have a consistent brightness anyways most people will not know this is the effect of a polarizing filter.

The polarizer effect on a wide angle sky.

Notice the change in color of the sky from the left to right in this scene. Shooting a wide angle photo with a polarizer will result in some portions of the scene being unaffected by the polarizer.

Neutral Density filters
If you like the silky-smooth effect on the falling water of the many waterfall pictures on the site, then you like the effects of the Neutral Density (or gray) filter. Think of the Neutral Density filter as the Ray-Ban sunglasses of the filter world. The job of a Neutral Density (ND) filter is to reduce the amount of light reaching the camera lens without affecting the color of the scene.

If the light entering the lens is cut by 50%, then the shutter has to stay open twice as long in order to properly expose the scene. While the shutter is open for twice as long, the camera is picking up all the water movement that happens during that time and blending it all together in one shot. This leads to the blurring or “silk” or “cotton candy” effect on moving water. The darker the scene, the longer the shutter needs to stay open to get a proper exposure, and the more water rushes past the scene as the shutter is open. The more water the rushes through the scene, the more blending occurs in the result is a stronger effect. To achieve the silk effect, you need to have your shutter open for at least 1/15th of the second. Without taming light, this would result in a greatly over exposed image.

The silk effect is strengthened by the fact that the rest of your scene, the rocks and the trees, hopefully aren't moving while the shutter is open, and remain sharp in the resulting photo. So it's important to keep in mind that anything that is moving while the shutter is open will end up being blurred. This includes any foliage that may be moving because of wind or any people or animals within the scene. It's also important, since the shutter will be open for long longer than average, to use a sturdy tripod. Photos will be a blurred mess from any handheld shots with a ND filter.

There are three ways to darken a scene to get the silk effect on your water. The first is to shoot at night when there is less light. Unfortunately this also changes the colors of the scene and you limit the time available to shoot. The second is to close your aperture (increase the f-stop), which may not have been enough for some lenses, and may change or depth of field beyond what you want for your composition. The easy way is to use a ND filter.


*What's the difference between these two shots?*
The left image is shot with a shutter speed of 1/60th of a second. Fast enough to freeze the falling water as it fell in the air. No filters were used. Shots like these show great texture in the water and can help illustrate the power of large falls.	The right image was shot with a shutter speed of 1 full second. Which gives enough time for the water to move, creating a blur in the exposure. A ND8 filter was used to limit the amount of light to keep the shutter open without overexposing the image.

The neutral density filter can be bought in different strengths, once it will reduce the light slightly and others that are strong enough to tame direct sunlight. They are specifically designed to not alter the color of the scene. When buying a ND filter it’s recommended that you buy various strengths and use them based on the lighting conditions of your scene. If you could only just buy one, I recommend starting out with and ND8 for bright scenes or ND4 for those in the shade.

One may also choose to invest in a Half ND filter if they shoot a lot of landscapes. These specialty filters are half gray and half clear glass and are great for shooting scenes in which half the scene is of normal brightness (the ground) and half needs to be tamed by the effects of an ND filter (the sky). These filters come in different strengths, like a regular ND filters, but also varying degrees of softness in the transition between the gray half and the clear half. In the digital age I can't recommend a half ND filter as much as a regular ND filter anymore. If the landscape shot has lighting conditions that are so diverse, I recommend shooting two photographs, one at exposing for the ground or water in the other exposing for the sky. Then combine them in Photoshop.

A Sunset Waterscape taken with a half ND filter

The above photo was taken using a half ND4 filter with the grey half covering the bight sky and the lake through the clear half. This allowed for me to properly expose an otherwise troublesome scene.

The silk effect of a full ND filter can be imitated in Photoshop, but it is not nearly as good as the real thing. So if you want your waterfall photos to have to silk effect, I can't recommend a set of Neutral Density filters enough.

You're lucky that you're shooting in the digital age. Many of the filters created over the past couple of decades are now considered obsolete because the effects can be easily achieved using digital photo editing techniques. A few filters I mention above cannot. And if you want to enhance your photographs beyond what your camera can do out of the box, I highly recommend considering using filters.