What's an ND filter and when do you use it on your drone?
What's an ND filter?
An ND filter is a lens filter that blocks light, and is sometimes called a neutral density filter. You can easily click an ND filter onto the lens of your drone. This filter is made of dark glass. As a result, less light falls onto the image sensor of your drone. Thanks to this, your videos won't be overexposed soon. ND filters are available in different intensities. An ND16 filter blocks 3 stops of light, and an ND64 filter 6 stops, for example. This means that you extend the shutter speed with 3 or 6 steps.
Why do you use an ND filter on a drone?
An ND filter helps you to set the right shutter speed for cinematic video footage. You'll get a cinematic effect by creating the right amount of motion blur. Thanks to this, the movements of the image feel smooth and natural. To get this result, you have to adjust the shutter speed to the number of fps. You can do this with the ratio 1/(2x the number of fps). For example, if you record in 4K resolution with 25 fps, you should set the shutter speed to 1/50sec.
When do you use an ND filter?
You can use an ND filter to record with a long shutter speed during the day. You can't adjust the aperture for most drones, and the ISO value can't be set to less than 100. That's why adjusting the shutter speed is the only way to get proper lighting for a sunny day. You'll sometimes need an ND filter for this. Depending on the amount of lighting you want, you can choose an ND filter. The filters are categorized by stops. For example, use an ND16 filter if you want to extend your shutter speed with 3 steps.