Week 13- Georeferencing

The focus for this week in Intro2GIS was georeferencing and editing existing feature classes with a touch of 3D mapping. I used the Georeferencing toolbar in ArcMap 10.2 to georeference two aerial images of the UWF Campus based on the spatial references of an existing polygon and road feature classes. I matched known building corners and intersections from the feature classes with the buildings on the images and with a little help from a 2nd order polynomial transformation to account for distortion was able to spatially align both images.

After giving the images spatial references I used the Editor toolbar in ArcMap to add a building to the polygon feature class and to add a road segment to the line feature class. I addition to the drawing the new items I also used the Editor toolbar to update the attributes for the new items. This was an important step because the height attributes for the buildings came in to play during the creation of the 3D map at the end of the lab. Before moving on to the 3D section I practiced using one more new tool this week, the Multiple Rings Buffer (found in ArcToolbox under Analysis Tools>Proximity>Multiple Rings Buffer). I used this tool to display two buffer distances around the location of an eagle nest near the UWF Campus.

When all of the work was completed in ArcMap I opened up ArcScene to get a 3D perspective of the same areas. The aerial images are draped over a digital elevation model raster with their base heights set to the raster data. The building are extruded using their height listed in the file's attribute table and the whole map has a vertical exaggeration of 5 to enhance the features because the area is so flat.

There were a lot of tools and functions to work with this week but overall they were pretty simple to use. More importantly, the editing and georeferencing tools will be invaluable as I continue in this GIS adventure and I find myself working with new, incomplete, or incorrect data.