On the front of an first person view (FPV) quadcopter you will find a small camera. This camera broadcasts real-time footage through a video transmitter and antenna. The video is fed to the pilot using video goggles or a screen. This feed is used to pilot the craft, and it literally feels like you are sitting in the cockpit.
FPV camera technology originated using analog surveillance (CCTV) camera technology. You will find similar technology at the core of today's hardware. Manufacturers have simply repackaged it for ease of use. Modern FPV cameras are purpose built for common applications like front mounting on a quadcopter frame.
This article focuses on the widely used analog technology. There is currently only one player in the digital HD FPV video space. Amimon who makes the Connex HD system. Because that product is an all-in-one solution, we aren't going to mention it in this article.
In this article we dive into the concepts and applications of these small cameras. For further reading, see the master article: Components & Anatomy of an FPV Quadcopter
Before diving into the nitty gritty hardware details, we need to clear up a common newbie misconception. In most cases, the brilliant HD videos you see online are NOT the same video feed the pilot sees while flying. High definition video filmed from an FPV quadcopter is done so using an additional flight recorder camera mounted on the frame.
A great example can be seen using one of the most breathtaking pieces of FPV flight video ever filmed. Big shout out to Gab707 - find his YouTube channel here. Gab was nice enough to provide both the final cinematic cut as well as the raw footage from his goggles.
You will find two types of image sensors on FPV cameras: CMOS (complementary metal oxide semiconductor) and CCD (charge coupled device). The job of these sensors is to convert light into electric charge and output it as electronic signals. The different ways these sensors digitally capture images has an effect on the image quality. Lets dive into the specifics of each system as they relate to first person video flying.
This image sensor uses a rolling shutter which captures an image from top to bottom. This continuous capture motion is prone to a 'jello' effect. These sensors are lower cost, lighter weight, and consume less power. That makes them a great match for micro FPV systems.
This image sensor uses a global shutter which captures the entire images in a single moment. This provides a better image quality through vibrations and quick movement. This capture method also performs better in high and low light conditions. This can be important for flying at sunset, sunrise, or at night. The slightly heavier design and focus on image quality makes these sensors desirable in mini and above FPV systems.
For a more technical and in-depth look, see the article CCD vs CMOS from Teledyne DALSA.
In front of the image sensor, you'll find a lens. Normally the lens is attached via threads on a case of some type. Depending on the type of lens you use, the field of view (FOV) changes. This is an important consideration depending on the type of flying you'll be doing. Wider lenses are going to be better if you're doing tight, technical flying. Narrower, long lenses are better for higher altitude and long distance flying.
Here is a great video comparison of a 2.1mm vs 2.8 mm vs 3.6mm FPV lenses:
The most common lens sizes for FPV are as follows:
2.1mm lens has approximate 158 degree field of view
2.5mm lens has approximate 147 degree field of view
2.8mm lens has approximate 130 degree field of view
Forward speed of your quadcopter is determined by the angle of attack. It is natural to maintain a level view plane as you pilot your craft. Most FPV racing frames offer some type of adjustable angle for the FPV camera. While flying, the camera does not move. As the picture changes, it is because the orientation of the quadcopter is changing.
The natural tendency when flying with straight forward speed is to keep the picture at a natural view. This means the horizon sits centrally in the image with ground and horizon taking up roughly half the top or half the bottom of the screen. Because of this tendency, fixing the camera at a higher angle naturally influences higher the forward speed of your craft.
This is very important for beginners to consider. We recommend starting your early flights with little to no camera up-tilt. A flatter camera angle will make it easier to hover in place without gaining forward momentum. Beginners should start with 0-10 degrees of tilt and slowly increase it as they feel more comfortable. Professional pilots fly with anywhere between 25 and 60 degrees of up-tilt. The best place to start experimenting with this is on a simulator. The risks of crashing are gone and it is easy and free to grasp the concept.
As you browse cameras, you'll come across specs that outline TVL. TVL or television lines is a definition for an analog camera's horizontal resolution power. This is comparable to pixel measurements found on new digital systems. In short: the higher the TVL rating, the higher quality the video image quality.
In theory FPV pilots want the best image quality possible. The higher the image quality comes with some complications. The increase in data can cause latency in the video system. High speed, high precision flying requires super quick reaction times. Less latency provides a 'crisp' handling feel and enables more technical flying.
600TVL cameras are the most widely used camera for good reason. This is the sweet spot when it comes to the quality / latency trade off. These cameras have 20ms of delay or less.
Working with older analog camera systems means we have to carefully consider aspect ratio. Today, any digital content will be 16:9 widescreen or wider. This older analog video technology is still using 4:3 standard ratio in most cases. This should be considered when buying video goggles. You'll likely want to match your video goggle and camera aspect ratio so the picture is not stretched.
Infrared Blocked vs Sensitive has an influence on the nighttime performance of your camera. IR blocked gives better daytime performance and better color. IR sensitive gives you a better picture in night or low light situations. Often times cameras will switch to black and white when the light gets low enough. Often times this is a setting that can be controlled from camera to camera.
The dynamic range of a camera influences the picture quality when there are contrasting light/dark areas on an image. As an example, sunrise or sunset can blow out the dark areas of an image if you're looking into the sun. Wide dynamic range equalizes the image preventing blowouts or blackouts.
As mentioned in the beginning of the article, early FPV pilots were using modified CCTV surveillance camera gear to fly. With the explosive popularity of the hobby, advances from companies in the space have brought new application specific advances. These advances are great because the hobby is becoming more and more accessible.
An on-screen display or OSD is traditionally an external piece of hardware. They are used to display real time and static information as an overlay on a video feed. Most commonly an OSD is used to display battery information. Manufacturers began to incorporate these pieces of hardware within or as an add on for FPV cameras. Cameras like the RunCam Swift 2 are removing the need for an external OSD.
The surge of popularity in micro FPV is largely thanks to the small form factor cameras available on the market. Manufacturers like FXT have created combined camera + video transmitter combos not much bigger than a quarter. This has spawned a craze in the micro world with quadcopters like the Tiny Whoop.
Here are Controller Craft we curate a database of on-board cameras. See our listing of FPV cameras in the product database.
Last updated on February 7, 2017