As drone technology has improved, so too has the quality and image performance of the cameras attached to them. Current model drones such as the Mavic 2 Pro come with an extremely impressive camera manufactured by Hasselblad – one of the leading camera and image sensor companies in the world. Older model DJI drones such as the Phantom 4 Pro (20MP camera) and the original Mavic Pro (12MP camera) produce very high quality aerial imagery in both video and still formats. And as drone technology advances, the ability to produce professional quality video and photography from a stable aerial platform has given photographers more options in how they can produce content.
As with normal DLSR and mirrorless cameras, drone cameras can benefit from the use of neutral density filters and polarisers to control shutter speeds, both for still images and also for video. Neutral density filters are very useful for video to control the shutter speed to create a more natural and cinematic feel to videos. Drone ND filters can also be used to reduce the available light to create long exposure images from drones in the right flying conditions.
NiSi produce a range of neutral density filters for the Phantom 4 Pro / Advanced, Mavic Air and the Mavic 2 Pro in variations from a 2 stop ND filter through to a 10 stop ND filter with multiple densities in between, polarisers and the Natural Night Filter. All of our NiSI drone filters are manufactured with the highest quality optical glass and come with our proprietary Nano Coating for added scratch protection, easy cleaning and reduced reflections. NiSI drone filters are extremely lightweight and designed to be balanced for the gimbals when attached to the DJI drone cameras.
Control drone camera shutter speeds with ND filters for better quality video footage
Neutral density filters are used when shooting video to help maintain and appropriate motion blur in between each frame, allowing you to create a cinematic look to your videos that match what we are used to seeing on television or when watching a movie in the cinema. The basic rule for maintaining the correct shutter speed when shooting video is called the “180 degree rule”. This rule means that the aim is to achieve a frame rate to shutter speed ratio of 1:2 (or as close to this as possible). If you are shooting at 25 frames / second you will require a shutter speed of 1/50secs. At 30 frames per second, a shutter speed of 1/60secs is required and so on.
The shutter speed when shooting video is how long the shutter stays open for each frame of the image, of which there could be 25, 30, 60, 120 or 240 frames per second depending on what settings and resolutions you wish to shoot at. When shooting video without ND filters, the shutter speed of any of the cameras used by DJI drones may be as high as 1/1000th secs or even 1/2000th secs on a bright sunny day. If you are aiming to produce the best quality video footage possible you will require a neutral density filter to reduce the shutter speed down to match the 1:2 frame rate to shutter speed ratio.
The ND filters you will require will be completely dependant on the amount of light available to your camera. In the example above of 1/1000 secs shutter speed without an ND filter, if you are shooting at a frame rate of 30 frames per second, an ND16 / 4 Stops ND filter would be required to reduce the light available to the camera sensor to achieve the desired shutter speed of 1/60 secs.
To calculate the correct density of NiSi neutral density filter you would require when shooting video with a DJI drone, use the NiSi Filters app which is available on both Apple iOS and Android devices.
Please note – the video above references the original DJI Mavic NiSi drone filters which have been discontinued. NiSi drone filters for the Phantom 4 Advanced / Pro are still available to be purchased at the time of publishing this article.
Control drone camera shutter speeds with ND filters for long exposure images
The cameras attached to any of the above mentioned DJI drones allow for shutter speeds as long as 8 seconds, which is quite long considering drones are used for aerial photography. To shoot sharp images at shutter speed generally considered to be “long exposures” in the range of 0.25secs – 8 seconds the conditions would need wind free to keep the drone itself as stable as possible. Shutter speeds can be controlled by using NiSi drone neutral density filters just as normal DLSR and mirrorless cameras can.
DJI drones come with a “tripod mode” for improved stability when flying which again can assist in the stability required to shoot longer exposures. Tripod mode effectively improves stability by applying more torque and power in specific directions, allowing the drone to become more stable and therefore allowing for longer exposure times when shooting still photography. Tripod mode will impact on the speed of the drone movements in any direction, and can be effective when flying extremely close to objects or when there is a low level of wind.
By using ND filters with your drone you will be able to capture movement and motion in elements such as water, traffic, or clouds by allowing the drone camera shutter to stay open for longer periods of time. The longer your keep the shutter open for, the more movement and motion that can be captured in your scene. The more light that is available in your scene, the darker or more dense of a filter you will require to shoot long exposures. If your shutter speed without an ND filter is 1/500 secs, a NiSi drone neutral density filter such as the ND1000 / 10 Stop will allow you to shoot an exposure time of 2 seconds without any variations to aperture or ISO.
Again, to work out the correct NiSi drone neutral density filters to achieve your desired exposure times when shooting long exposure images, use the NiSi filters app for either iOS or Android devices to simplify the process and to make those calculations as easy and as quickly as possible!