Thursday, February 16, 2012

Week 5 Projections Part I

Nearly a third of our way through this first semester.  It's going by faster than we realize.

Our goal with the projection study is to recognize our earth has no perfect shape and that no matter which direction we look at it, its' gonna wobble. The key is learning how to frame our perspective from an accurate, realistic view. We are to especially recognize that one can not cut up our round earth (like a basketball), lay it flat like a pancake on a piece of paper and expect it to be accurately whole,  without wrinkles.   Thus, the scientist made projections.     Here's our study of Florida using three different projection angles. 



Following is how I made this map.

Process Summary

1)    1)  Moved ProjectionsPartI from R:drive to S:drive, created folder for Week5-ProjectionsI-QueensFlood.  Extracted all files into new file.
2)   2)   Opened ArcCatalog in second window, copy & moved cntbnd.shp to new map document.
3)   3)   Opened toolbox, Data Management Toolbox, Projections and Transformation, Feature, Project.
4)      In Project dialog box, set cntbnd as Input dataset, set cntbnd_utm16 in my S:/Intro/Week5_projectionsI/projectionspartI folder. 
5)     4) Still in Project dialog box, in Output Coordinate System field, accessing Spatial Reference Properties dialog- select- Browse Coordinate System window, navigated to Projected Coordinate Systems folder to UTM then NAD 1983, then selected NAD 1983 UTM Zone 16N, add. In Geographic Transformation drop selected NAD_1983_To_HARN_Florida.  OK, calculating.
6)     5)  Green checkmark. Yea!
7)     6)  Added cntbnd_utm16 to map. Saved map as Week5-Florida_project1.  Warning did not come up.
8)     7)  Inserted two new data frames into map.  Renamed original layer as Albers, 2nd layer as UTM & last layer as StatePlaneN.  Moved cntbnd_utm16 into UTM layer. Deleted it from Albers layer.
9)     8)  In UTM layer, Began at 3 above, Project tool, had created this layer with original cntbnd layer as input followed  with Florida State Plane North (Harn feet) projection (Projected Coordinate Systems>State Plane> NAD 1983 HARN (US feet)   Saved created file as cntbnd_stateplanen added to layer State Plane N.  
10 9)  In layout view, moved three maps beside one another to view.  
1110)  On Albers data frame, activated, attribute table, added field in dialog box “AREA”, short integer as type. OK, on AREA column, click dropdown- selected calculate geometry, yes on warning box, in Calculate Geometry dialog box- AREA as property, use coordinate system of data source (Albers) units- changed to square miles. Ok
1211)  Repeated 11 for layer UTM and StatePlaneN.  Discovered later I forgot to save file after Albers layer, had to redo the steps to input information for chart.
1312)  The above went very smooth and quickly.  It was creating map that bogged me down. Had to rediscover how to select multiple attribute rows not contiguous with no relationships.  Tried Select by: attribute box had right syntax but wrong approach. Later (much later) in attribute table, used control key to select counties- Alachua, Escambia, Polk & Miami-Dade.  
1413)  Created separate layer for selected counties. Changed select color to one more visible with border at 0.40.   Activated label feature for the selected county layer, converted labels to annotations to manipulate labels to best view and uniform appearance for greater comparison on each map.Decided this was best presentation for comparison purposes. (Instead of different color for each county).
1514)  Created data table in Excel with values for comparison projections, imported to map. 
1615)  On each map renamed layers for legend, gap 5, re-sized patch to 15: 7.5 ratio for each entry. Inserted North Arrow (2 looked more symmetrical), added scale bar.  For each map activated, full extent to find best scale ratio- chose 1:10,000,000 as best view for all. Could not do full extent afterwards; it changed ratio so set 1:10,000,000 as default on all three maps.  Albers Map the projection is curved so adjusted fit inside border for best view.
1716)  Inserted titles in each map, drew rectangle box for full map title, selected background, inserted title, used title dialog box for best insertion.  Added neatline around all elements with background color.   17) Straightened appearence.  18) Nearly forgot to put it on blog for assignment.






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