Hi,I'm new to ENVI, and working on DEM using ALOS PRISM. Does anyone know and might help me? Q1: what is the DATA means in the Cursor Location/Value when I pointed on any point of the image after the whole DEM extraction process finished and I loaded the generated DEM. i.e: DATA: 49 means what? That's not the elevation data. The elevation data only able to view when I loaded the generated DEM in 3D SurfaceView and we can see the elevation in Cursor Location/Value. i.e: Elev: 297.105 I read back the ENVI help, found that the DATA shows in Cursor Location/Value is actually the natural log of magnitude. What does this means? Q2: I masked out the sea in the generated DEM and I can see the sea is mark as Zero in image window, but during 3D Surface Viewing, the seas still have value. So, what should I do in order able to load the DEM with the sea define as zero in 3D Surface View? Q3: How am I able to read the elevation data without loading it in 3D Surface View? Besides, is there any way to export the elevation info to a .txt file or any file that I can read the data instead of image. Q4: During the DEM generation process, is Delaunay Triangulation being used? any others literature reading behind the ENVI process? I hope someone can help. Thank you very much.