Hello,
I'm new to IMC and am also trying to convert a raster (multibeam bathymetry geotiff) to an at5.
I followed all of the above instructions (correct ellipsoid, I have the tfw file, and set the Alpha to 1 and mix/max resolutions to 1 and 32) but with no luck. I end up with two files after running the program, _3DTexture_1.at5 and _3DTexture_2.at5 but I contacted someone at Navico and they said I should have three zoom levels and that the at5 files I created won't show up on their machine.
Any insight into what might be the problem would be much appreciated!