Elevation Data
Elevation data (altitudes) can be included in planned routes and waypoints created using the map, if there is a Digital elevation model—DEM tile installed for the area being mapped.
Installing tiles with elevation data involves downloading them and sharing them with TripLogger.
DEM tiles can be downloaded from CGIAR. Choose the 5 x 5 degree tile size
with the Geo TIFF
format.
TripLogger can handle tiles with .tif
, tiff
, .tar
, .tgz
and .zip
file extensions. When using zip
, tar
and tgz
formats ensure that the
filename of the TIFF file inside the archive has the same first component as
the archive file, e.g. srtm_37_03.zip
must contain srtm_37_03.tif
in the
root folder of the archive. The original zip
files from CGIAR should
work without alteration.
Note that when sharing via AirDrop and possibly other routes, multiple copies of the file can be created in the Downloads folder, causing them to be renamed and subsequently fail importing into TripLogger. Check the import error message for the filename being referred to. If it has been renamed, remove duplicates from the Downloads folder.
In principle accessing tif
files directly should perform better as they
don't need to be decompressed, but the iPhone and iPad will import them into
the Photos library first, from where a copy can be shared to TripLogger. Note
that on iOS 17 the TIFF image must be saved to Files first, then shared to
TripLogger. Alternatively the tar
format should perform well as it is not
compressed and not suffer intervention from the Photos app. However
compression saves a lot of space and seems to perform well.
To view and delete the imported TIFF tiles, select the Elevation TIFF tiles
option under the advanced section of the settings page.