TransDEM Forum

I happen to have, in my hot little hands, an 880 MB ESRI DEM file compiled from 5m LiDAR data, pulled from the ELVIS portal (GeoScience Australia portal for elevation data). I also happen to have a 6.07 MB ESRI DEM file of the same type, covering a much smaller subset of the same area. Both are MGA94 coordinate, which (I am under the impression) is essentially the same as WGS84 for our intents and purposes.

TransDEM can load the 6.07 MB file, but not the 880 MB one. Given that I also have another DEM file covering the same area, at lower resolution (DEM-S 1 sec), which TransDEM can load, is there anything I can do to load the big one? If not, is there a way I can load the subset data into the lower resolution DEM?

Applying some RTFM, I see that the Fill Up DEM and Add DEM functions would let me merge the two different DEMs I can load, which would let me get some high res data for a small area and complement it with the lower res DEM data that covers the route area completely. I may have to look into that if there is no way to load the full size hi res version.