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TINs and DEMs

 

This assignment delved into TIN and DEM’s elevation data models. The main difference between the two is that raster uses DEM while vector data uses TIN.

I began by visualizing a 3D TIN of a valley/gorge using a TIFF image. (Image 1 below)



For my second analysis, I converted a DEM to TIN, reclassified the data, and used a weighted overlay to develop a suitability model for a ski run.


When comparing the DEM and TIN layers side by side, the TIN has more dimensionality and elevation texture than DEM does. Because of this, I would think that the TIN layer is more accurate. Overall, the smaller the elevation slope the greater the difference between TIN and DEM. In this area, DEM understates the slope while TIN overstates it. 

I created a couple more models with TIN, and really enjoyed playing around and getting to know how to work with TIN models. The biggest differential element I learned about was in the last step. I found that when creating a modified TIN, using Edit TIN tool, this allowed the elevation features to appear in a real life format. It went from a mostly 2D with slight 3D elements to a total environment composed of 3D. This was achieved as the edges were hardened and enunciated very sharply, adding texture and life to the elevation. 


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