Why Does My Drone Need an ND Filter?

Short. The purpose of ND filters is to reduce the amount of light that hits the sensor, so they can be called your drone’s sunglasses.

An ND filter reduces the amount of light that hits the sensor, resulting in longer exposures. Reducing the amount of light may be necessary in several cases. For example, when shooting in the mountains, where there is a lot of snow, or when shooting on sandy beaches. In such situations, the camera’s minimum shutter speed may not be sufficient to provide the required exposure. In addition, ND filters can be used to emphasize movement (such as the drops of a waterfall) or to give an image a softer, surreal look, or even to remove dynamic objects from a landscape. Using a quadcopter filter will help you set the right exposure for rivers, waterfalls, and other “moving pictures”.

An ND filter is more than just a piece of tinted glass placed in front of a camera lens. A high-quality light filter should reduce the level of light, while not affecting contrast, provoking the appearance of glare and, most importantly, affecting sharpness and detail. Therefore, the choice of filter manufacturer is extremely important. Inexpensive filter sets produced by small companies may not meet all requirements and, at the same time as reducing the amount of light, “complement” the image with unnecessary glare and reflections. Therefore, it is important to choose a well-established manufacturer.

The effect that can be achieved with an ND filter is almost impossible to recreate when processing a picture.

But ND filters are much more important for shooting video. The thing is that modern cameras allow you to shoot with a very fast shutter speed, which is useful for taking clear photos, but vice versa is not suitable for shooting video. When shooting at a fast shutter speed, the footage may come out too sharp and jerky. Some quad cameras allow you to limit the amount of light with a bladed diaphragm (like the Phantom 4 Pro/Adv or Mavic 2 Pro), but even that doesn’t always help. It is impossible to close the aperture to infinity, because. this can cause loss of detail and degradation of the image, and also affects the depth of field, which may be unacceptable for any particular task (especially for long lenses for Zenmuse cameras). Therefore, to increase exposure, it is logical and simple to use ND filters. Thus, we have the opportunity to shoot video at the required shutter speed in the region of 1 / 100-1 / 120 to obtain “cinema”, while not closing the aperture more than necessary and without the risk of getting a blurry image.

Neutral density filters vary in how dark they are. The higher the density of the filter, the less light it lets into the frame.

ND filters will help you take spectacular photos of water – a raging mountain river instantly turns into milk foam. And take a picture like this

At the same time, the owner of the copter can take such a picture even in sunny weather.

The f-stop is the ratio of the focal length of the lens to the diameter of the entrance pupil. And if in simple words, then the larger the “F-stop” number, the less light will enter the lens. This will give you more control over the exposure of the image or video you are trying to capture in flight.

To see how the different ND filter models relate to the F-stop level, see the table below.

In addition to ND filters, there are many filters for your drone, and all of them will give different results:

CPL/PL are filters that have a polarizing layer and allow you to remove glare and reflections from reflective surfaces, water, glass, etc. (except metal). In addition, such filters can enhance the color of the sky and foliage, but you need to remember that they only work at a certain angle.

The action of the polarizing filter is most pronounced when the angle between it and the sun’s rays is 90 degrees. If the sun is behind the copter or vice versa shines into the lens, then the effect of the filter will be almost invisible or not noticeable at all. In addition, any polarizing filter has a certain percentage of blackout, this should also be taken into account when shooting at sunset or sunrise to control shutter speed and sensitivity.

Gradient filters are filters that fade smoothly from one side to the other. Such a filter can be considered a variation of the ND filter, but providing a smooth transition from a darkened part to a completely transparent one. Such a filter can be used to darken the sky while keeping the ground bright. For example, this can come in handy when flying over a forest on a clear day. The lower lighter part will give detail to the trees, while the upper part will be darkened.

REMEMBER: the use of a particular filter may partially reflect your style as a cameraman or photographer. So choose the one that suits you.

To sum it up, easy-to-use quick-release filters can help you get high-quality and beautiful shots and minimize the amount of post-processing in the editor. ND filters will not only not interfere with aerial photography enthusiasts and videographers, but also help to raise the quality of the material to a higher level.