ND Filter

Remember that with video, you have a narrow range of shutter speed options. This can make it extremely challenging for shooting in certain conditions, especially if you want to take advantage of wide f/stops for limited depth-of-field effects. With just 1/30, 1/60, and 1/90 as your primary shutter speed choices, your f/stop options are minimal, especially in bright light.

If you want to take advantage of a wide range of f/stops, get a neutral density filter. (See Figure 3.3.) A neutral density filter is simply a dark filter that cuts down the amount of light going through your lens. This allows you to use wider f/stops (smaller numbers) to better control depth-of-field as needed when the light is bright. Generally, a neutral density filter that cuts the light by three f/stops is a good strength. Such three-stop filters will be given either an ND8 or ND9 designation (using the two most common ways to specify the light-stopping power of a neutral density filter).

Figure 3.3 A neutral density filter is simply a dark gray filter that cuts the light going into the camera.

Some photographers use a variable density neutral density filter for this purpose. This is a filter that is built with two filters—one filter rotates in front of the other and gives an infinite variety of darkness for the filter.

If you don’t have a neutral density filter, and you do have a polarizing filter, you can use that polarizing filter to cut the light by almost two f/stops. That won’t give you as much control, but it can help.