Drone Cinematography and The Micro Four Thirds’ Advantage
Since the 2008 introduction of the Micro Four Thirds sensor, both still photography and filmmaking industries have significantly expanded adoption of the technology. Specifically developed to meet the demand for portability, without sacrificing image quality, Micro Four Thirds (m4/3) sensor adoption has taken off because of key three advantages: portability, performance and pricing. Considering the technical challenge with the integration of an m4/3 camera onto a drone platform, there are only a handful of companies have managed to achieve this feature successfully. The advantages of this sensor format for aerial cinematography are very clear and make it a standard of reference for advanced users and professionals alike.
As seen in the figure on the left, the Micro Four Thirds Sensor is in a sweet spot, sitting in the mid-range of all sensor sizes. While the sensor has historically suffered from “middle child” identity, getting lost in the shadows of its larger and smaller siblings on either side of the spectrum, the M 4/3 sensor offers unique strengths that make it an ideal option.
The holy grail in aerial cinematography is portability with lighter payloads meaning significantly fight times. Full Frame sensors, larger than M 4/3, are housed in a larger, heavier camera body. The heavier payload requires bigger drones and demands more power (and less battery life), which is totally impractical by many. Thus, the smaller sensor, housed in smaller, lighter camera body offers significant advantage. Up until now, the majority of drones have been compatible with 1” sensor DSLRs. But the 1” sensor is only slightly smaller than the M 4/3.
In addition to the smaller sensor size, the elimination of a mirror box and shorter flange focal length, lightens the load even more. Flange focal length refers to the space between where the lens is mounted to the camera body and the camera’s image sensor. Therefore, a shorter flange length equates to a smaller, lighter a camera body. It also means most manual lenses can be adapted for use, including lenses that are smaller and lighter. A smaller sensor also emits less heat and therefore requires less battery power. Installed on drones, a minimal payload, less heat, and longer flight time all yield significant production advantages.
Sensor Size and Image Quality
Many will (erroneously) assume portability comes with a cost to quality. As discussed earlier, drones have traditionally featured a 1” sensor. A larger sensor size typically yields better performance through better low light capability and wider dynamic range, it is not the be all end all in creating beautiful cinematography. Crop factor and image processing also factor into image production.
Pixels and Resolution
The quality of any camera is influenced most notably by the quality of the sensor, not the megapixel resolution. This is a common myth that is perpetuated by many camera manufacturers, even cell phone cameras. Our m4/3 sensor is 12 megapixels. This translates to our 4.63 microns (μm) pixels being almost twice as big as on a 24MP m4/3 sensor while providing better low light performance, greater color information per megapixel and increased dynamic range.
Not all M 4/3 sensors are made equal. The XDyanmics’ M 4/3 sensor has a unique advantage, offering a larger crop factor at 1.89 (compared to standard M 4/3 crop factor of 2.02). While it may not seem like a huge difference, because crop factor directly impacts perceived lens focal length even the slightest crop factor difference produces marked differences. As an example, let’s take a typical 18mm lens or the standard M 4/3 we get a perceived focal length of 36.36mm. However, with the XDynamics’ larger M 4/3 sensor, we get a focal length of 34.02mm. This may appear to be only a slight advantage, but even a few mm difference over all your lenses provides more options to crop in the post process.
The M 4/3 sensor is integrated into mirrorless camera systems. In mirrorless cameras, image information and light are translated directly on to the sensor. Because the photo is processed directly on the sensor, mirrorless cameras offer fast and highly accurate focus. With no mirror and no separate AF sensor, autofocusing is also performed on the sensor itself. This means that the distance measurement can be calculated using the entire sensor area, with no limit on the number of distance measuring points. The result is a faster, more efficient, and highly accurate autofocusing system. Mirrorless cameras also create images with less noise simply because of the mechanics. Pressing the shutter in a mirrored camera system causes the mirror to swing up to let light in. This motion creates “camera slap” noise and additional camera vibration or movement. As well, the mirrorless camera system allows for film makers to use viewfinders when shooting. When shot in continuous mode, this smaller sensor also realizes cooler conditions which contributes to less image noise.
Wide Array of Lenses
The Micro Four Thirds sensor boasts an open standard, with a wide array of compatible lenses on the market. With an abundant choice of premium quality lens options from many brands (such as Panasonic, Leica, and Olympus), film makers can really harness their ability to create high quality productions. This open system increases creators’ ability to collaborate on wide variety of projects in both still photography and film. Now, creators can share glass across projects and optimize selection to lighten their payload while achieving the desired look.
Sharper Images via Telecentric Lenses
In digital cameras, the output from the lens is imaged by an image sensor. Oblique incidence of light on the sensor device affects the formed image due to reduction in the brightness of light or deviation of the optical axis. To limit light incidence angle with a non-telecentric lens, one would have to increase the size of the lens and camera body considerably, which is impractical as it would directly affect portability and cost. The M 4/3 sensor resolves this issue through its emphasis on telecentricity. Telecentric lenses are designed to deliver a large amount of effective light (with a sufficient intensity and non-deviated optical axis) to the image sensor and significantly lower distortion. In contrast, non-telecentric lenses cannot deliver effective light for the imaging size, but the telecentric-type lens can deliver effective light for the entire imaging range.
Technology is great but only if you can afford it. Earlier we discussed the wide array of compatible lens options for a M 4/3 camera. A wide array of lens options, across multiple brands, gives film makers the latitude in creating a production kit adequate for the project within budget with the freedom to expand as they required. Because lenses with wider fields-of-view are considerably more expensive, every millimeter can equate to a significant cost savings.
The XDynamics’ Advantage
XDynamics has worked to bring big aerial production capabilities to the hands of film makers everywhere. With the Evolve 2, a single operator, small form factor drone, cinematographers can now realize the M 4/3 advantage without breaking their budgets.
It’s been 12 years since the initial introduction of the M 4/3 sensor. Since then, not only has the world of imaging adopted the technology but we are now also seeing pivotal integration into aerial cinematography. Offering portability, performance and attainable pricing all make for a revolutionary moment for drone cinematography.