Q: What drones are compatible with DroneViewer?
A: I have tested DroneViewer with the Autel EVO, GPS-enabled GoPro HERO cameras (like the HERO 5 black), DJI Mavic Pro, Mavic Pro 2, Matrice 200, Phantom 4 series, and Phantom 3 series. It will also work with the Phantom 2 as long as you have a FlyTrex Core 2 logger installed. It may work with the Inspire2, but I don’t have sample video to verify this. Remember to turn on Video Caption subtitle feature in your drone app to make your drone stores trajectory data.
Q: I have a Phantom 4 Pro V2.0 and I’ve turned on Video Captions in the Go App but SRT files are not created. Why?
A: The Phantom 4 Pro v2.0 embeds the SRT data into the movie itself. DroneViewer will detect this and decode the data. One difference between the SRT data in a separate file and embedded SRT data is that the embedded SRT data is not date/time stamped. Therefore the file creation date is used as the start date in the case of embedded SRT data.
Q: Will DroneViewer work with the Mavic Air?
A: Unfortunately the Mavic Air does not store trajectory data in the SRT file so DroneViewer will not display the drone’s route. I don’t know why DJI made that decision, but I can’t think of any reason why the lat/lon/alt/speed couldn’t be added. Mavic Air owners may want to contact DJI and request that flight log data be added to the SRT file.
Q: Will DroneViewer work with the DJI Spark?
A: No, the Spark does not store trajectory data.
Q: Why does my route look jagged? Why does my compass appear to spin erratically sometimes?
A: While it’s great that DJI logs the drone’s flight data into an SRT file, the speed of the drone is not recorded to the file and the latitude and longitude are not stored in high precision. DroneViewer uses the time-stamped lat/lon values to estimate the speed. The lack of precision means the drone speed and direction can be inaccurate and appear to vary wildly. DroneViewer applies a smoothing function to dampen the speed variations. While this helps, it’s not a perfect solution. Ideally, DJI would modify their SRT file data to include native drone speed and higher-precision latitude and longitude. (There are other ways to extract the flight data to higher-precision but they are not as convenient as the SRT file method).