to put on a UTM grid or lat/long graticule. Note on both maps the UTM grid is square, and the graticule is taller than wide, which is accurate. One map has a UTM projection, and the other a quasi-Mercator. options change. You can remove the elevation coloring, the MICRODEM default, change the vertical exaggeration, or adjust the illumination. and pick the OpenStreet map files. MICRODEM wants the native OSM, with lat/long coordinates. It will show both the SHP and the DBF files, you can select either. Put this on both maps, to notice that MICRODEM reprojects the data if necessary (however, the shapefile must be lat/long, WGS84). Note that the two profiles are very similar but not identical. You can right click on the map, and create a legend. Note that the UTM DEM is more generalized, missing many of the ridge crests and valley bottoms. Pick the grids. In this case, the order determines the sign of the result, and also the number of points used for the computation since the grids are different (3′ versus 100 m). If you get a histogram of the differences, you can see that in this case re-interpolation has created some elevation differences >, 30 m. Note the ‘unsaved’ in the title bar of the maps. The grids have been created in memory, and will not be saved unless you choose the Note the ‘unsaved’ in the title bar of the database The file has been saved to a temporary directory, and will be deleted when you close the program. To save it permanently, Create point shapefile, Reopen the file from the permanent location, and use this option to create the SHP and SHX files so you can use the database in another GIS program. MICRODEM stores the Lat/Long in the DBF file, which can be edited in a wide variety of programs (e.g. Excel). Pick the grids. Pick June 2010 first, and then Jan 2009. Positve values will be higher in the second time period, and show where the dunes migrated. : Valid Points in second grid, Values. Pick the Difference grid for the second grid. Pick an opacity factor (e.g. 15%). Note the maximum changes are to the east of the dune crests. If you repeat with the June 2010 grid, the maximum changes will be on the crests at that time. Everything below cutoff: and pick a slope value (e.g. 50%). All points with a smaller slope will be marked missing. What will be left are the slip faces. You could save this if desired. If you just wanted the locations of the slip faces, you could reclassify all the valid values to have a single code. which will create a grid, in which each slip face will have a unique entry, and a table with information about each feature. Pick ‘Scan angle’ for the color coding on the General tab.and re-Draw. This shows the flight lines. The colors range from Source.