I believe the majority of FPV pilots would agree that the invention of the DJI O4 Air Unit Pro has opened a whole new world of possibilities when it comes to utilizing small-format FPV drones for amateur and professional video projects. The largest yet 1/1.3” CMOS sensor offers a huge upgrade in information gathering capabilities and combined with D-Log M capable video and drastically improved RockSteady stabilization modes, it truly is a game changer for the FPV pilot aspiring to monetize their hobby.
That said, while this is hands-down the most capable digital VTX camera system we have ever seen made available for FPV drones, it is not immune to needing a little help to be even better and more versatile.
Allow me to introduce to you the subject of today’s article: the Freewell Standard Day 4-Pack of ND Filters for the DJI O4 Air Unit Pro.
Before we get into what I think after using the Standard Day 4-Pack from Freewell, let’s get into what ND filters are and when you might need them.
WHAT ARE ND FILTERS?
Neutral Density (ND) filters are camera filters designed to limit the optical density of light entering the camera and hitting the sensor. Limiting the amount of light that gets to a camera’s sensor has to immediate effects to an image or video. Every ND filter comes with its own numeric value (unless it’s variable, which is a different topic for a different article). These numeric values will be displayed as ND8, ND16, ND32, and so on. The higher the number on the ND filter, the darker the lens is and the more it blocks light from getting to the camera’s sensor.
One might deploy an ND filter on an oppressively sunny day or otherwise brightly lit environment to reduce blowouts in the highlights and general over exposure of the image or video. Deploying an ND filter might also be necessary for capturing more motion blur or achieving a balanced motion blur for particular looks for images and videos.
But that begs a new question…
WHAT IS MOTION BLUR?
Motion Blur is the amount of blur that is generated by movement from subjects within frame of a camera shooting photos or videos. There are generally three different broad varieties of motion blur that a creator may want to achieve while shooting video:
- Normal Motion Blur: This is generally considered a cinematically acceptable amount motion blur that appears normal to the human eye. Achieving normal or balanced motion blur is done by following the 180-degree rule between your frame rate and shutter speed. When adhering to this rule, your shutter speed’s denominator (the number on the bottom of the fraction) should be double the value of your frame rate. If you are shooting video at 24 frames per second, you should set your camera’s shutter speed to 1/48 (or 1/50 if 1/48 is not available). If you are shooting at 60 frames per second, you should set your camera’s shutter speed to 1/120.
- More Motion Blur: This is achieved by slowing your camera’s shutter speed down. If you would normally shoot a video at 24 frames per second and 1/48 shutter speed to capture normal motion blur, you may instead shoot at a shutter speed of 1/24 or 1/12 depending upon the amount of blur you want. The more you slow your shutter speed down, the more motion blur will be captured. Be aware though, too much motion blur can look sloppy and unprofessional.
- Less Motion Blur: This is achieved by speeding your camera’s shutter speed up. If you normally shoot a video at 24 frames per second and 1/48 shutter speed to capture normal motion blur, you may instead shoot at a shutter speed of 1/100 or 1/200 (as cameras typically do not offer shutter speeds of 1/96 and 1/192). The more you speed your shutter speed up, the less motion blur will be captured. Be aware though, not enough motion blur can look too smooth and unnatural.
HOW THE STANDARD DAY 4-PACK HELPS THE O4 AIR UNIT PRO
Now that we know what ND filters are, how they affect exposure values on your photos and videos, and how to achieve different types of motion blur while adjusting your camera’s shutter speed, let’s talk about the Freewell Standard Day 4-Pack, how they help while utilizing the O4 Air Unit Pro’s video for professional projects, and what I think of the product overall.
The Standard Day 4-Pack by Freewell features four ND filters that include an ND8, ND16, ND32, and ND64 lens. These four filters come in their own dedicated carrying case made of standard plastic and lined with glass-safe foam for optimal shock resistance and protection. It also comes with a microfiber cloth for wiping your camera lenses and filters.
Applying the ND filters from Freewell for the DJI O4 Air Unit Pro is as easy as I have ever seen. It is as simple as aligning the non-bracketed end of the filter to the bottom lip of the camera housing for the O4 Air Unit. After aligning those two parts and sliding the filter into place on top of the bottom camera lip, cant the top-end of the filter (which has a bracket sticking up off of it) back into the upper lip of the camera housing until it “clicks” into place. To remove the filter, simply apply light pressure on the back of the bracket (pushing away from the camera lens) until it pops out of place. Be careful not to let the filter hit the ground or floor, especially if it is a harder surface as it may lead to damage to your filter.
Overall, the Freewell Standard Day 4-Pack met and exceeded all of my expectations, the values of each filter were consistent with previous Freewell and non-Freewell ND filters. Applying the filters to the camera is a breeze and the footage I was able to collect with the O4 Air Unit Pro even on the brightest sunny days was incredible. While the O4 Air Unit Pro stands on its own as a capable video tool, the Freewell ND filters included in the Standard Day 4-Pack made it even more capable for shooting in a variety of environments — not just for balancing the exposure value of the image, but for striking the right balance of motion blur for my FPV video projects.
The movement of FPV drones of any variety is much more intense than most GPS, RTF drones. Having the tools necessary to bridling that intensity and manipulate it the way I want to manipulate it to achieve a certain kind of look and feel in my video was fantastic. It would not have been possible without ND filters, and Freewell is one of the best in the game when it comes to manufacturing ND and camera filters for creators. It was, for all intents and purposes, the perfect marriage between two of the most reliable companies in the camera drone space.
If you are interested in adding the Freewell Standard Day 4-Pack for your DJI O4 Air Unit Pro, consider using my affiliate link by clicking here. As I do on my YouTube channel when featuring and/or reviewing products sent to me, I’d like to offer you a disclaimer: I do not promote or share affiliate links for products unless I approve of their feasibility and performance and would use them myself. When you use an affiliate link I share with you on my platforms or here on The Droning Company’s website, you can have peace-of-mind knowing that the product you will receive will work as intended and be of immediate benefit to you as a professional or a hobbyist drone operator.
I highly recommend Freewell for all things camera and drone filters and accessories. The Standard Day 4-Pack for the DJI O4 Air Unit Pro is no different. This product is well worth the $50 price tag and is actually much less expensive than competitive products, saving consumers 30-40% while delivering equivalent or even more value.
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