GIS5935 Module 2.1: Surfaces - TINs and DEMs

               In this lab, we explored two types of elevation data models - Digital Elevation Model (DEM) and Triangulated Irregular Network (TIN). The DEM is raster-based and information is stored in grid format, while TIN is vector-based and uses irregularly spaced points that were calculated according to the connections of sets of triangles for contouring. Because of this, the DEM has smoother curves in its contour lines, while TIN has pointed/jagged contour lines. The DEM contour lines in this instance also have a few more lines due to the data parameters.  

              The TIN contour lines are likely more accurate, as TIN can differentiate between more complex terrain than DEM contour typically can (depending on resolution). TIN uses irregularly placed elevation points that vary based on data density, but DEM is a grid with elevation values stored within the grid cells. This generally means that higher density point areas indicate complex terrain in TIN, but because DEM uses grids, this could result in less terrain detail depending on the resolution. When it comes to determining which one to use for a project, it’ll depend on your needs. You may want to use a TIN if your project needs more accuracy to show the complexity of the terrain, but DEM data may be more accessible.