Filters for Landscape Photography
An essential part of most landscape photographers equipment is their variety of filters. The use of filters allows the photographer to control light and achieve certain effects. While some of these techniques can be done in post production, others require the use of filters to remain a high quality. Filters can often be pricy and it can be hard to choose what filters to get. This is a short introduction to the recommended filters for landscape photography.
Neutral Density Filters is a filter placed in front of the lens to reduce the amount of light entering the camera. This allows the photographer to use a slower shutter to create motion blur and/or create a shallower depth of field. Say that you are photographing a waterfall, and to achieve the desired look, a shutter of 5 seconds is needed. By bumping your aperture as high as you can, it may be possible to achieve the 5 second shutter if you are shooting in dimmed conditions. However, if you want to obtain a optimal aperture and you are photographing in brighter light, achieving the 5 second shutter is not possible. Therefor a ND filter is used to reduce the amount of light, allowing you to use a longer exposure to get the desired effects.
A detailed guide to Neutral Density Filters can be found here.
Graduated Neutral Density Filters are pieces of dark glass or resin placed in front of your lens. Just like a normal Neutral Density Filter it allows less light to enter the camera. What differentiates these two filters is that the Graduated filter is only half way darkened, while rest of the filter is clear. That means that the filter only darkens parts of the image, while the rest is left alone. Graduated ND’s are available in three degrees of darkness, one – two – and three stops. To clarify, this means that some of the filters allows more light to go through than others. At this moment you may ask yourself why in the world you would only darken parts of a image, but I’ll come back to that in a bit!
Reverse Graduated ND Filters
Just like normal GND filter, reverse graduated filters are only partly darkened. The difference is that instead of the darkest part of the filter being at the top and the brightest in the middle, a reverse GND is the other way around. Say that you have 3 stop Reverse Grad Filter. The darkest point (3 stops) would be at the transition to clear glass, while the top of the filter would only be 1 stop. In other words it allows more light to enter the top of the darkened part than the bottom – while the lower half is still blank.
Reverse ND Grads are normally used when the sun is about to set, and the light just above the horizon is very bright. A normal graduated filter would handle this just find, but you would quickly see that the top of your image would be very dark, since this is where the darkest point of the filter is, while the horizon may still be bright. The Reveres ND Grad is as I mention darkest in the end of the darkened area, so by placing this at the horizon you will now have a perfectly balanced image where the horizon doesn’t blow out and the top sky is still kept at the correct brightness.
(Abbreviation: PL or CPL – Circular Polarizer)
A favorite among many landscape photographers is the Polarization Filter. The filter serves many purposes and photographers use them in a variety of scenarios. Since the filter is somewhat darkened, expect the need of a slightly longer shutter speed Most common uses of PL or CPL filters are:
Often when photographing waterfalls, rivers, lakes or other elements with a wet, shiny surface, there is a fair amount of glare. Especially if the sun is out and reflects in the elements. In this scenario a Polarization Filter is often used to remove unwanted glare and reflections.
Increase Contrast in Sky
You might notice that a photographer often uses a Polarization Filter during the daytime. The darkened filter does a good job in increasing the contrast by darkening and bringing out the blues of a sky, while whitening/brightening the clouds. Note that due to the maximum polarization in 90 degree angles to the sun, a Polarizer Filter will not always be able to properly darken the entire sky, and you might need some further developing in softwares such as Adobe Photoshop.
Polarizer Filters also does a great job in bringing out the colors in the landscape. During seasons such as spring and autumn many photographers leave the CPL on throughout the day. Since the filter increases contrast it also helps revealing colors.
I won’t spend to much time writing about UV Filters as, quite honestly, I rarely use them and they don’t have much of a purpose in my opinion. The only reason to use this filter is to protect the glass of your lens from scratches and damages. UV Filters are a piece of clear glass that is screwed onto the front element of your lens, and won’t improve the image in any way. Also during nighttime it might be good to know that a UV filter will do more bad than good, as it reflects certain light and leaves spots of glare on the image.
Some people might disagree with me and claim that it’s essential to use an UV Filter to protect your gear. The truth is, if you use your lens cap when you are not taking images, your equipment will be fine. Use common sense and don’t leave the lens laying around without the lens cap.
What is your opinion on UV Filters? Have you used them?