Advanced Video Editing

Canon XF300

Adjusting the ND Filter

The ND (Neutral Density) filter is equivalent to putting on a pair of sunglasses. Under bright conditions, the ND filter allows you to maintain a greater range of f-stops, allowing for greater aperture control by essentially reducing the amount of light that enters the lens, preventing overexposure under bright conditions. 

So the reason why you would use an ND filter is to give you more flexibility when setting the aperture and shutter. You can use larger apertures to create shallower depths of field or to achieve a sharper image. The filter allows for longer exposure times to emphasise motion such as softening the appearance of a turbulent waterfall.  But before you set the aperture and shutter, and even before you decide to use the gain and white balance, you need to set the ND filter. Under low-light conditions, you really don't need to use the ND filter, so switch it off before you adjust your aperture settings. 

The ND filter appears just behind the iris ring. There are 4 settings:

  • OFF - No filter (use this setting indoors)
  • 1 - ND1 1/4 - reduced brightness by roughly 3 stops of light
  • 2 - ND2 1/16 -reduced by roughly 4 stops
  • 3 - ND3 1/64 -reduced by roughly 6 stops
Make sure to adjust the white balance each time you change the ND filter.