The thirteenth and final lab exercise of our Introduction to Geographic Information Systems course, like the previous one, introduced us to multiple tools and functions of the ArcGIS software. Our first task was to georeference a raster image that included no coordinate information to a referenced vector layer of UWF campus buildings. This involved matching points on the raster image to the corresponding points on the vector layer. ArcMap then alters the raster image based upon these control points. Exactly how the image is altered depends on the transformation chosen by the cartographer. In the example above, I used the 1st order polynomial transformation for the north raster and the 2nd order polynomial transformation for the south raster. I applied a 3rd order polynomial transformation on the south raster as well, but the 2nd order transformation appeared more accurate.
The second portion of the lab introduced us to editing in ArcMap, an integral component of the software that I am sure will be utilized much in future courses. In this case, we added one building (the gymnasium, in yellow in the map above) and one road (Campus Lane, in red). In addition to the line and polygon additions, we edited the corresponding entries in the layer attribute tables.
The final activity this week involved importing our map of the UWF campus with the addition of our edits into ArcScene to explore the three dimensional capabilities of the software. As seen below, the ArcScene layout was exported as a JPEG and then imported into ArcMap to add the legend and text. Again, this was a mere introduction to a component of ArcGIS that could be extremely powerful for certain projects. I can imagine its use in archaeology, for example, in visualizing and reconstructing complex sites.
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