One of the most challenging aspects of drone photography and videography is mastering exposure. With most drone cameras, you can control the exposure by adjusting the shutter speed and ISO (the aperture is set at a fixed level). But even with a quality camera and optimized settings you can still experience glare, overexposure, harsh shadows, and the dreaded jello effect.
Drone camera filters are semi-transparent glass accessories that can be attached to the outside of the camera. There are several different types of filters, but the primary purpose of all filters is to control the light that enters the camera — which directly impacts exposure levels.
Learning how to use neutral density and polarizing filters can help you consistently create high quality aerial imagery and provide you with a quick and easy tool for mitigating exposure-related problems.
Neutral density filters
Neutral density (ND) filters reduce the amount of light that passes through the camera lens, which gives you the ability to slow down the shutter speed without risking overexposure. ND filters use a numeric naming system the allows you to easily identify the specific amount of light the filter reduces (for example, an ND 2 filter reduces the light by one stop and lets in half the light; an ND 4 filter reduces the light by two stops and lets in ¼ the amount of the light, an ND 8 filter reduces the light by four stops and lets in ⅛ the amount of light, and so on).
ND filters can reduce glare, improve saturation, and enhance color. When you’re filming on bright, sunny days, using an ND filter gives you the ability to capture smooth video quality that might not otherwise be possible.
The following three ND filters cover a broad range of lighting scenarios, and are great tools to keep on hand whenever you fly:
- ND 4: If you’re capturing video or photographs in conditions with decreasing light (such as dusk or dawn) the ND 4 filter can be a great option as it reduces shutter speed by two stops.
- ND 8: An ND 8 filter reduces shutter speed by three stops, and provides better image control during cloudy conditions.
- ND 16: When conditions are bright or partly cloudy, an ND 16 filter is a good option as the darker glass filters out more light and reduces the shutter speed by four stops.
Most quality drone cameras do a good job of automatically adjusting the shutter speed when you’re using ND filters, but if you’re not getting the results you expect, you can always alter the settings manually. Consider using manual exposure especially when the sun is in the frame: you’ll need to make a creative decision about how to balance the bright sky with the darker ground, depending on the overall look you’re trying to achieve and what post-processing your footage will undergo.
Here’s a quick sample of drone video footage captured with an ND filter.
Polarizing filters are specifically designed to filter reflected light. Using polarizing filters enables you to:
- Minimize reflective glare: Whether you’re filming a remote lake in the mountains or capturing the perfect sunset at the beach, reflective glare from bodies of water can negatively impact the quality of your videos or photographs. With polarizing filters, you can minimize reflective glare while still capturing reflections in the water from the surrounding scenery. Polarizing filters also reduce reflective glare from buildings, rivers, and other objects in urban areas.
- Reduce haziness: Even when the weather conditions are clear, distant scenery can appear hazy. Polarizing filters reduce the hazy appearance, and enable you to capture images with dark blue skies and landscapes with vibrant, saturated colors.
- Limit post-production work: Another bonus of polarizing filters is that they limit post-production work. Because images and video captured with a polarizing filter already have rich, dramatic color, you won’t have to spend as much time in post production making edits and modifications.
Polarizing filters have become a favorite accessory for landscape photographers — though the benefits are clearly applicable to all types of photography and videography.
The bottom line
Drone camera filters give you an additional method for controlling the light that enters your camera. Mastering the exposure levels of your photos and videos is challenging, but with the right drone camera filter you can reduce glare, minimize reflected light, and create beautiful, color-rich aerial imagery — even when lighting conditions are less than ideal.