I have found many cases where the elevation data used in Litchi’s Mission Hub (when the “Above Ground” option is checked) disagrees with what is displayed in Google Earth Pro. I am wondering if anyone else here has worked with elevation data and can share their knowledge about this.
Here is a simple Litchi mission where the “Above Ground” option is checked:
Notice that according to the heights displayed in Litchi that WP1 is higher than WP2. The drone would start at 6.5m above take-off and fly down to 4.2m above take-off to remain 6.5m above ground.
Now, I export that mission to Google Earth Pro and see this:
Notice that Google Earth Pro shows WP1 at 63m MSL which is 6m above ground as expected.
For WP2 in Google Earth Pro, I see this:
According to this, WP2 is at 67m MSL (also 6m above ground). This suggests that Google’s elevation model determines that WP2 is higher than WP1.
Both Litchi’s elevation data and Googles elevation data cannot be correct. The person who shared this data with me says that in reality, the ground below WP2 is indeed higher than that of WP1.
I know that there is always going to be some error in elevation data models. Is this example within the expected elevation data accuracy?
I use Google’s Elevation API in my programming. I find it fairly straight-forward to use. I once heard that Litchi used “Mapbox” elevation data. I do not know if that is correct or not. I tried the Mapbox TileQuery API but I find it confusing and unusable because it is only accurate to the nearest 10m:
Mapbox Documentation: Also, since the elevations are returned in 10 meter increments, the results may lose some nuance.
I would enjoy hearing anyone else’s experience in using elevation data and what is used in Litchi’s Mission Hub.