TOPAZ wants to convert DEM to UTM

[davidv]

I'm trying to compute flow directions and accumulations by TOPAZ but if I'm trying to run it the warning shows up that I have to convert DEM to UTM before running TOPAZ. I do not know where the problem could be. I'm using metric units and plane coordinate system as the area which I'm going to model is very small and the terrain was measured in the field. Could you please help me to solve this problem?

[Chris Smemoe]

You need to define your projection before starting your project. You just need to select the Edit | Current Projection menu and select either the Local Projection option if you don't know what projection your data is in or the Global Projection option and then define the projection of your data. Once you do this, you should be able to run TOPAZ. You cannot run TOPAZ with data defined in Latitude/Longitude coordinates. Let me know if I can help with anything else.

Chris

[davidv]

Dear Chris, thank you very much for your answer. However, I still can't run TOPAZ. I set the local projection when opening WMS with the new project and then set the local projection when opening ascii DEM. But when I try to run TOPAZ the same warning appears (see attached screenshot).

[Chris Smemoe]

The problem is that your DEM X/Y coordinates fall within the range of -90 and 90 (north-south) and -180 and 180 (east-west). WMS does not support running TOPAZ with coordinates that fall in this range of values. You could change the DEM header to have values higher than this or you could convert from a Geographic projection to another projection.

Chris