Module 6: Georeferencing, Editing, & 3D

University of West Florida campus georeferenced maps indicating UWF Gym (Bldg. 072) and Campus Lane road, as well as the location & buffer zone of a protected eagles nest. 

Module 6 focused on how to georeference. The goal initially for this lab was to create common points between the known (in this case, Building & Road feature classes) and unknown (raster image(s), or the University of West Florida campus maps-).

We started by working with University of West Florida campus maps – one for the north campus, and a separate south campus map. This allowed us the opportunity to figure out how to piece together relatively simply two separate maps with a known layer (Buildings layer and Road layer) Choosing the Control Points wasn’t too difficult once I got started and took time to examine the map(s). While I kept the UWF North map in the First Order Polynomial transformation, I felt like the UWF South map was best aligned in the Second Order Polynomial transformation.

After the University of West Florida campus maps were georeferenced against the Buildings & Road layers, we then georeferenced the Heritage Hall (a building on UWF Campus) Parcel Survey. Because the UWF campus maps we georeferenced earlier were images from before Heritage Hall was built, we used Google Maps to locate where Heritage Hall was built. We then started adding Control Points based on the Survey (unknown) features to our known Campus map(s). I had initially used the Campus Drive road (not to be confused with Campus Lane) as one of my early points and the map was heavily distorted – I then realized after a lot of cross examination with the Google Map image that I had misunderstood the Survey and that there were multiple “peaks” in the Campus Drive to choose from. Once I figured out where exactly I was looking at in relation to my Campus Maps, more accurate Control Points were placed.

This lab also gave us an opportunity to create a Multiple Ring Buffer for a conservation easement for a bald eagle nest on UWF campus by using the input EaglesNest feature. The conservation easement requires a 330-foot perimeter, and a further 660-foot protected area around the easement to consider any developments that would be detrimental to the nest. We also digitized a Campus Lane road (line feature) and the UWF Gym – Building 072 (polygon feature) and indicated them individually on our maps.

 

LiDAR map of the georeferenced UWF map(s) of above.

Creating a 3D Scene

Using provided LiDAR data (UWF_Lidar.lasd), we created a New Local Scene with elevation surfaces. Once we filtered the points down from “All Points” to “Ground” points, converted LAS Dataset to Raster, and added an Elevation Source Layer – we could really see the University of West Florida campus maps gain depth. I elected to use the UWF_DEM elevation surface.

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