For example, OPTI has a built-in Optiflow Sensor (a downward facing sensor), which functions by picking out the patterns on the ground to ensure that the drone maintains a straight position.  ATTI, conversely, works a bit differently. With the ATTI, the drone employs other techniques apart from the external sensors to keep the drone in the right orientation and altitude. Thus, the drone can hover in place, or drift slightly around with the wind serving as a push. You will also find a GPS in some drones, and they help the drone to maintain coordinated and precise flights and landings.
While DJI may be the first name you think of when it comes to drones, it isn't the only game in town. You can also look at models from Autel Robotics, Parrot, PowerVision, and Yuneec. Others have dabbled in the consumer drone space and exited quickly—GoPro pulled its Karma after a rocky launch and poor sales, and 3D Robotics tried to get in with the Solo, but also gave up the fight to focus on the industrial and enterprise spaces.
The quality of the video captured by these drones is fine for flying them and it is good enough to post on social media. However, the video quality is not HD. This can easily be seen when playing the recorded video on a screen that is larger, like the typical laptop screen that is 1080p. Video that is 720p will look pixelated and fuzzy when viewed at full-screen size on a screen that is 1080p high. 
Generally speaking, drones that cost less than $100 bucks aren’t worth your time. They’re flimsy, they lack advanced features, and they’re almost always squirrely as hell in the air. But Tello is different. Despite the fact that it retails for only $99, it boasts a boatload of high-end features and functionality. Under the hood you’ll find a 14-core Intel vision processing chip, flight stabilization tech from DJI, a 5 megapixel camera capable of shooting 720p HD video, and a battery that gets you 13 minutes of flight time.

best drones under 100 amazon

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