Module 6 - Georeferencing & Editing

    This week, in the sixth GIS lab, it was about georeferencing and editing maps.

    This week’s lab had a big emphasis on georeferencing, as it was the most intensive part of the lab. So, to start, we added all the layers that were in the geodatabase provided. These being the roads, buildings, and eagle nest to the map. Next, we then placed out first jpeg of the northern part of University of West Florida (Uwf_n) to the map. With it, we opened the georeferencing pane, and centered it to the location where the rest of our map elements were, as the jpeg was placed in a null zone in the ocean. With everything all in one area, we began georeferencing the unknown jpeg to the known building and road locations. To start, we lined one of the building's polygon corners to the jpeg image where the building was. Once done, we added a control point from the unknown jpeg location to the known building location.

    With the first control point placed, the jpeg was altered to coincide more with the correct geometry of the building polygon. Following this, another point was placed between the end of a road on the jpeg unknown, to the known location we had on the roads polyline. As you can see on the map below, we continued to plant control points till it lined up as best we could with our map elements. With about ten control points for the first jpeg, the Random Mean Square  Error of Uwf_n was 6.866694.

    After georeferencing that section of the map, we then went ahead to do the same with the southern part of University of West Florida (uwf_s1). With about six control points plotted, we then used the 2nd order polynomial to fix the transformation, as it was intentionally distorted. This let us learn that we could use the orders of polynomial transformations to align the unknown jpeg more correctly to the map appearance. With a few more control points and transformation to a 3rd order polynomial, the random Mean Square Error of Uwf_s1 was 1.089242.

    Next, we did another georeferencing with a parcel illustration of the heritage hall. With use of both google maps and our earlier georeferencing of Uwf_n, the random Mean Square Error of Heritage Hall Parcel Survey was 0.617325. However, it must be noted, the appearance of the georeferencing matters more than the RMS, as even with a low RMS the appearance may not be one to one with its transformation.

    With the georeferencing done, we next learned how to properly edit in ArcGIS. Where next we opened the editing tool to add a polygon of a building that was not represented on the map. On Uwf_s1's northwest corner there was construction on the now completed UWF gym. Using the create feature in the edit pane of ArcGIS, we drew the perimeter and made a polygon for the gym. Following that, we also added a new polyline to represent Campus Lane on the east side of Uwf_s1. Still using the editing tool, a line was made from the double road heading east, up to connect with the northern double line to represent Campus Lane. 

    Lastly, we prepared the conservation easement for the Eagle's nest at UWF, which you can see on the insert map below. First, we added a hyperlink to an image of the Eagles nest to the points attribute table. This allows us to click on and view it if and when we were to view the points data. I have also provide the same link at the end of this blog. Following that, we added a multiple ring buffer around the nest’s location. The reason as to why is the easement UWF made was 330 but from the Florida Fish and Wildlife Commission it had to be 660. Using the tool from the georeferencing pane, both were added to the map. Thus, bring us to the complete map below that I made.

    This lab really made excellent use of the tools ArcGIS has and made me far more confident in making my maps for class.

Eagles nest picture link: Here