Module 3: ArcGIS Field Map Mobile & Sharing Maps and Introduction to Projections



      Module 3 lab allowed us to look at the difference between map projections when projected on the same area. Each map highlights four Florida counties (Alachua, Escambia, Miami-Dade, and Polk) that are projected in three different map projections: Albers Conical Equal Area, NAD 1983 UTM Zone 16N, and NAD 1983 HARN State Plane Florida North FIPS 0903 (US Feet). Not only is there a slight visual difference amongst the map projections, the Area in Square Miles table shows us that there is mathematically a difference between each projection.

     While we started out initially with data in the Albers projection with this project, we then used that dataset to reproject into UTM 16N and State Plane Florida North respectively using the Project tool located in the Geoprocessing Pane. The UTM 16N map shows Florida rotated more counter clockwise and distorted compared to Albers & State Plane Florida N projections. Florida is in two UTM zones (17N & 16N), so UTM 16N isn’t the best projection for Florida. State Plane Florida North projection is mostly only good for North Florida – Miami-Dade and Polk Counties are not in North Florida, so the State Plane Florida North projection also isn’t the best projection. Out of the three options, Albers Conical Equal Area is the best projection as it minimizes distortion when considering standard parallels.


     Module 3 also allowed us to take ourselves into the field and collect data points via ArcGIS Field Maps. Once we created our domain and new feature classes, we collected five points of interest that were similar (in this case, road signs) and created an ArcGIS map. Each point of interest was given a Condition descriptor that indicated whether the road sign was in Like New Condition, Good Condition (some wear), or Damaged (broken, hard to read, etc.). My five points of interest were road signs with the above conditions to consider – I unfortunately picked an area that was aged, but not in need of repair. But, I wouldn’t have known that had I not gone and picked those points first-hand! 

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