NASA makes available a Digital Elevation Model for the Moon in GeoTIFF format. I am trying to use QGIS to create a map of a specific region, bounded by certain values of latitude and longitude. From what I can gather (I am not a GIS person; this is my first time using QGIS), the GeoTIFF in question is encoded as
elevation, but I need to work with latitude and longitude.
I load the file in question into a new project by adding a new raster layer and selecting the file. However, when I add a grid decoration, it is displayed as
y. In addition, if I want to select a point or region, I must input
I tried extracting elevation contours (using Raster->Extraction->Contour), add that layer, and try to add fields via the Attribute Table (specifically the
$y attributes, as suggested in this answer). However, the computed values are
From what I can gather, my CRS looks correct:
+proj=ecq +lat_0=0 +lon_0=0 +x_0=0 +y_0=0 +a=1737400 +b=1737400 +units=m +no_defs. It looks correct to me (again, not my wheelhouse) because it shows that the map is in a simple cylindrical projection, with lat/lon zero at xy zero, over a sphere with radius 1,737,400 m (the correct radius of the Moon).
I also tried converting the raster into a vector (using Raster->Conversion->Polygonize) and work with the resulting shapefile to no avail.
How would you go about loading the linked GeoTIFF in QGIS and displaying a map of, say, upper-left corner in lat/lon (30 deg, 0 deg) and lower-right corner in lat/lon (-30 deg, 30 deg). The map would have a grid separated in, say, 5 degree increments.