Currently all of DroneDeploy’s elevations are relative to the takeoff location. It would be awesome to have an app that can correct my data to have an elevation of above sea level.
One solution could be to correct the elevation image EXIF data before uploading the images to be processed.
This is so so needed. Maybe a secondary app that records gps data from your phone from the take off point, then coverts it to above sea level and then syncs with the app on take off ?
It does not sound that simple for me. What GPS/Glonass give you is the geometric height (based on the reference elipsoid - WGS84). When we talk "elevation above sea level, we are talking about orthometric height (related to the geoid). Considering that it is not possible to model the geoid for the entire planet, due to the constant changes in its shape, it will be not feasible to provide the orthometric height. The only solution, besides allowing the user to introduce the orthometric height from the home point -it would work for small areas to be surveyed- would be to improve the system to consider regional geoidal models that would be uploaded to the drone, by the users. Such a solution is not easy or cheap.
While we believe the real solution would be a local adjustment to a known datum on the map, something we expect to be working on in Q2, we are going to enable a feature toggle to use the AMSL estimate that the GPS on DJI drones provides. In combination with the barometer on the device, we think this may at least be a good start for you.
We can then incrementally add the ability to provide an offset / datum on top.
@JimBob - would you be willing to test this out on your account if we can enable it in the next few weeks?
Hi James thanks for your reply. That would be great ! Im working with a team of surveyor’s very soon to test the GCP function snd they need AMSL data in their maps. Speak to you soon. Jim here is a link to my website www.gingerinnovations.co.uk
Thanks @opteyndt. I have been using imagery from a Yuneec H520 which is fine as long as you don’t use GCPs because of the MSL tagging, but have been trying to decide what to try if I wanted to compare a GCP mission against the P4P I normally fly. Looks like a good option.
If you’re targeting surveying jobs then data geometry precision is essential. Even when you only would do volumes it is best to apply ground control points. The offset terrain will help to correct for a change in elevation reference level but the rest of your geometry should be handled in the photogrammetry process.
I use GCPs on every job, hence why I am working with Yuneec and DroneDeploy to try and get their systems integrated. We’ve got two new firmwares that are being tested right now for the H520, but ultimately the issue will come down to DD being able to handle MSL. Should be a column driven option when submitting the coordinate file.