On this part of the webpage we inform you about known problems with TopoFlight products and how you can avoid them until a new software version is released.
In TopoFlight's MissionPlanner, the download of SRTM data doesn't work anymore. The altitude data are now available via a different internet sources and in a new version (v3 instead of v2.1). The actual release of MissionPlanner uses a link to the old source and is not compatible with the new format. Currently we are working on a new release where this problem will be solved. Until then, you will find a workflow below on how to obtain SRTM elevation data yourself and integrate it into TopoFlight.
Step 1: Which SRTM tiles are needed?
The third step for the SRTM import in MissionPlanner shows which tiles of SRTM are needed for the selected area.
Step 2: Download the tiles.
SRTM data are available at 1 arc second resolution or at 3 arc second resolution. Use one of the following links and adabt the WGS84 Lat/Lng coordinates to download the required files.
1'' resolution:
https://e4ftl01.cr.usgs.gov/MEASURES/SRTMGL1.003/2000.02.11/N47W008.SRTMGL1.hgt.zip
3'' resolution:
http://e4ftl01.cr.usgs.gov/MEASURES/SRTMGL3.003/2000.02.11/N47E008.SRTMGL3.hgt.zip
For the download a EOSDIS Earthdata login is required, which you may create free of charge.
Step 3: Convert to GeoTiff.
Import the HGT files into a 3rd party software such as QGIS and join them into one GeoTiff.
Here, You will find the merge function in QGIS:
Raster -> Miscellaneous -> Merge
Pay attention to the coordinate system of the exported GeoTiff.
Step 4: Import in MissionPlanner.
The last step involves importing the created GeoTiff into MissionPlanner. To do this, use the "Import DTM" -> "Tiff DEM" function.
Make sure to select the right coordinate system of your GeoTiff before importing the data and creating the Quadtree File (.qtr).