A Triple Threat: Georeferencing, Editing, and Arc Scene

Hello all,
      This weeks post for my Intro to GIS class is all about what my title has alluded to; Georeferencing, Editing, and Arc Scene. The data for the lab was provided by UWF, featuring UWF through two aerial images, a building footprint layer, roads layer,a local eagle nest, and a Digital Elevation Model for the Arc Scene work. The maps below were both compiled in ArcMAP, however the 3D map was originated in Arc Scene. There were many overall objectives for this week as each of these topics can easily be given its own Lab Week and beyond. However a rundown of some of the bigger objectives is below.

• Georeference data using Control Points and proper distribution
• Georeference an unknown raster image of the campus to known vector data (i.e. buildings & roads)
• Interpret Residual and Root Mean Square errors
• Digitize new building and road features
• Edit data features and attributes
• Create hyperlinks in ArcGIS to data stored on a personal drive
• Create Multiple Ring Buffers
• Practice overlaying data in a 3D environment

Of the above the newest term should be Georeferencing. This is the registration of an image without a known reference to a dataset or group of features with known coordinate system etc. So below I took two un-referenced images of UWF and using the buildings and roads feature layers was able to add reference information by matching up location in the road and buildings layer to locations on the imagery. This is done through a set of linked control points. Essentially im telling the image, this spot on the image correlates to this point on this building or road layer. After enough of these points the image is able "referenced" because it now knows where it spatially belongs.

Above is my Georeferenced Raster map. You can see that its divided into three parts. The main component being the georeferenced rasters whereby the aerial images were matched up to the building and road feature location. Additionally the UWF Gym was edited onto the building layer, and Campus Drive was edited onto the road layer. The inset map in the bottom right shows the location of a nearby eagle nest relative to the main campus, and also depicts the mandated conservation easement area around the nest. 

The next portion of this lab involved taking the newly georeferenced rasters and the associated feature layers and adding them to Arc Scene. There, the layers were all floated on top of a digital elevation model. The building layer was extruded relative to the height of each building Then the entire image was given a vertical exaggeration of 5x, which only changes the visual appearance of the map, not any of the actual data values associated, but gives you a better visual interpretation of where height variation occurs.

This map which was created as specified above needed to be exported from Arc Scene and imported into Arc Map to do some of the finishing touches, such as applying the legend features and information. The image maintains a largely North up appearance, however due to the change of 2D into 3D and other exaggeration you can no longer dedicate a scale bar or North arrow given the ability to freely change the vantage point in Arc Scene.

I hope you have enjoyed these maps, they were definitely entertaining to create. It is neat to know how to create and edit your own layers and present them in different views, both 2D and 3D.