Many people think of the camera as like an eye, taking a perfectly true image. “The camera never lies” they say. You may have found, however, that your shots can come out looking quite unlike what you actually saw in the real world. This is where filters come in. The correct filter will make sure that the photo is a perfect representation of the scene, just as it appeared in your own eyes.
There are other uses for filters too. They can alter the mood of a scene, for example, or ensure that the picture comes out exactly as you would like. The filter fits across the lens of the camera, affecting the light which filters through. A combination of different filters can be used together, and since they are small and light you will find it sensible to carry a number of them with you when you go out photographing landscapes.
There are a few commonly used filters that will make a good start to your collection for landscape photography purposes.
The first type you should seriously consider investing in is a polarizing filter. It is highly effective, especially in indirect side light. The sky in a color photo will become richer and darker, while you will find it can capture the mood of fast flowing water and even the ethereal nature of mist. It can be used with black and white photography too, in which it will make the gray areas darker.
If you are interested in B/W photography you will find there are a range of filters directed specifically at you. In addition to the polarizing filter, which is the only one capable of working with either type of photography, the most common filter you will come across is the red one. It is most popular in a strength of 25. Red filters allow more red light through than they do light of other wavelengths. This will add to the power of your final image, particularly making the sky darker.
If you are attempting a shot where there is too much brightness in part of the scene it can affect the exposure. The sky is often much brighter than the nearby ground or shadows. It is not uncommon to find a difference of three light stops, for instance if the sky is giving an F/22 reading of 1/8 second and the ground of 1 second. In this case you must maintain the brightness of the ground while bringing the light in the sky down by three stops. A Neutral Density Filter of 0.9 can do this. ND filters are also commonly available in strengths of 0.6 and 0.3, which will reduce brightness by one and two stops respectively.
ND filters work by cutting out light from one half of the picture only, because part of the filter is shaded to its specific strength, while the rest of the filter is clear, letting all light from the scene through. They allow you to take photos of scenes where there is a large contrast in the amount of light in different areas, without any problems with exposure or any influence of the filter on the colors in the photo.
You may have had trouble taking photos on cloudy and overcast days too- which could be a big problem if you live in an area where such weather is common. Your photos probably came out looking dull and uninspiring. A warm-up filter can prevent this, allowing you to capture the beauty and detail of the landscape. Perhaps the best choice is the 81A, while you will find the whole 81 series to be highly effective in dealing with overcast conditions.
Don’t be tempted to buy any exciting sounding filter, though. You will find many on offer that are more detrimental than helpful to your shots. Color graduated ones, for example, will make the colors of your photos appear very strange and unnatural.