Camera filters can serve different purposes in photography. They can be indispensable for capturing scenery in difficult lighting conditions, they can enhance colors and reduce reflections, or can simply protect lenses. Most camera filters work by modifying the light before it enters the lens. The most common filters are UV, circular polarizers and neutral density filters. Camera filters are widely used in landscape photography, while street and portrait photographers don’t rely on them to the same extent. Below I will discuss the most common filters as well as buying suggestions.
UV filter:
Nowadays the primary purpose of UV filters is to protect the front elements (lens) of your camera. If you are clumsy or visit dusty, dirty environments, and you aren’t using another filter then a UV filter may be suitable for protection. Due to advances in dSLR technology UV filters are no longer a requirement to block out UV light. Some UV filters can however be responsible for a reduction in image quality through lens flare, producing a slight color tint or reducing contrast, so their use is somewhat limited.
Circular polarizer:
Circular polarizers work by filtering out light that is reflected directly toward the camera at specific angles. They work best with the sun to your side, or more technically when you are aiming the camera at a 90° angle from the sun.
By rotating the polarizing filter while composing your shot, you can see the effect the filter will have on your image.
There are three main applications for a circular polarizer:
- Improve the sky and clouds: When photographing a landscape with a blue sky, haze can cause the sky to be less vibrant. Using a polarizer, you can reduce the effect of the haze and reveal the true blue of the sky. Over polarization and/or wide-angle lenses can sometimes cause an unnatural artefact (blue splotch) or uneven look to the blueness of the sky so just look out for this.
- Reduce reflections off wet rocks: When you are taking photos of rivers and waterfalls sometimes the wet rocks can produce a glare as they reflect the light. You can use a polarizer to reduce this.
- Reveal what is underneath water: Using a polarizer can reduce the reflected light and reveal more detail underneath water. When you turn the polarizer, you increase/decrease the light reflecting off the water so you can reveal as much or as little of what’s beneath the surface of the water. It’s not all or nothing so experiment and see what works best for the particular image you’re trying to capture.
Neutral Density Filters:
Neutral density (ND) filters are darkened pieces of glass that reduce the amount of light entering your lens. They allow you to select combinations of aperture, exposure time and ISO that would otherwise produce overexposed pictures.
The most common applications for ND filters are:
- To shoot in the middle of the day in harsh light.
- To extend the exposure time to capture motion in your image. This is most commonly used with water with longer enough exposures a cotton candy effect.
ND filter vary between 1-stop and 10-stop. The amount of stops on an ND filter determines how much light they reduce, so a 10-stop filter will be much darker than a 1-stop. A good ND filter will not alter the color or hue in your image so will have minimal to no color cast.
To confuse the matter some companies use alternate names, below is a table of the common abbreviations for ND filters.
| F/stop | Fraction | Hoya, B+W and Cokin | Lee , Tiffen | Leica |
|---|---|---|---|---|
| 1 | 1/2 | ND2, ND2X | 0.3 ND | 1X |
| 2 | 1/4 | ND4, ND4X | 0.6 ND | 4X |
| 3 | 1/8 | ND8, ND8X | 0.9 ND | 8X |
| 4 | 1/16 | ND16, ND16X | 1.2 ND | 16X |
| 5 | 1/32 | ND32, ND32X | 1.5 ND | 32X |
| 6 | 1/64 | ND64, ND64X | 1.8 ND | 64X |
Graduated ND Filters:
By their very name graduated ND filters are either darker in the top or the bottom of the filter with either a “soft” or “hard” graduation (how quickly the darkness changes). They are excellent for landscape photography with clear horizons during the golden hour as the foreground may have a different exposure setting to the background. Graduated ND filters are only really useful if you have square filters as it’s hard to get the horizon lined up correctly with circular graduated filters. Graduated ND filters are not as well used as some of the other mentioned filters as there are other options including both blending, bracketing, and multiple exposures to obtain the same result.
Buying your first filters:
When you’re looking to buy your filters there are a few things to consider:
- There are both square and circular camera filters: If you’re a beginner stick to the circular variety until such a time you feel you need to switch to square. Leave these for the pros.
- Camera filters come in different sizes: If you’re buying camera filters for the first time purchase filters with the diameter of your biggest lens (or biggest future lens if you are looking to expand your collection in the near future). You can then use inexpensive step up rings so that the filters can go on multiple lens.
- Camera filters stack: You can screw a ND density filter onto another ND filter, or circular polarizer, effectively stacking the filters. You can do this as many times as you want but be careful as you may start to see vignetting on the outside corners of your photos.
- Buy less good quality camera filters rather than more bad quality camera filters: Quality filters matter and unfortunately they usually cost more money. When you spend a lot of money on your lenses it’s also true that any glass you place in front of them needs to be of equal quality. This is where not all filter are the same. Poorer quality filters may be more difficult to get on and off your lens, they may cause vignetting, and/ or they may cause color cast. Do your research and look at a price point that works for your current budget. You may be better to get less filters and spend a little more on each filter, or as previously suggested use step up rings so that your filters can fit on multiple lenses.
- If you’re only going to buy one camera filter start with a circular polarizer: If you can afford it look for brass filter rings and Schott glass: While more expensive these tend to get better reviews. Brass filter rings are easier to get on and off with different temperatures and Schott glass is considered some of the purest optical glass in the world.
- Which ND filters? If you’re going to buy ND filters primarily for landscape / midday photography consider a 3-stop and 6-stop which can stack to become a 9-stop. If you are looking for only small increases in shutter speed you may consider a filter set with a 1-stop, 2-stop and 3-stop ND filter.
Note: I know I said buy the best you can afford but this comes with a caveat. If you’re not sure if the camera filters are important for the type of photography you enjoy, maybe buy some middle of the road camera filters and see if you use them. You can always upgrade if you find that you’re using them a lot.
Which filter brands should you purchase?
- Good brands for circular polarizers include B + W, Breakthrough Photography, Hoya, and Tiffen.
- Good brands for ND filters include B + W, Breakthrough Photography, Hoya, and Tiffen.
- Fotodiox offer cost effective step up rings, where as Breakthrough Photography offer more expensive brass variants.
If you purchase a camera filter set that is bigger than your current largest lens diameter don’t forget to buy a lens cap for the filter so you don’t have to always take the filter off in between uses. You will also want to get a small filter pouch to keep your camera filters safe.
If you’d like to read more about essential equipment for landscape photography click here.
