PRO’S KILLER KIT #03 ND FILTERS
Nigel says… On a dull, overcast day, you can usually set a slow enough shutter speed to blur the trails of waterfalls, but if you want to capture movement in the rapids below, or if it’s very bright, you might not be able to set a slow enough speed, even at your lens’s narrowest aperture. The answer is to attach a neutral density filter to reduce the amount of light reaching the sensor, which enables you to set a slower shutter speed (and so let in more light for a correct exposure). ND filters come in a variety of strengths, from one stop up to 10 stops, and they can also be stacked (see page 50). A good starting point is a kit with two-, four- and six-stop filters.