This lab began with an introduction to ArcCatalog and an examination of the data available for view therein. I know viewing, creating and editing metadata is an important component of GIS, so I appreciate the introduction in this lab. The main activity, however, was the creation of three maps displaying data pertaining to Mexico. Each map was different, although all were designed to further our understanding of cartography and the essentials of a good map.
The first map we created was a choropleth map depicting the population of Mexico by state. I wasn't terribly creative in this map, altering primarily the data frame background to blue and adding a drop-shadow, grey background and rounded edges to the legend. I adjusted the scale bar to have a maximum unit of 1,000 kilometers; I also adjusted its properties to have four divisions and four subdivisions to make the units easier to use. Additionally, I experimented with the "mask" option for the state labels in an attempt to make them easier to read. However, my results were not quite satisfactory, due in part to the resulting appearance being quite different when viewed within ArcMap compared to the exported JPEG.
Our second map for this lab depicts the largest roads and rivers along with the railroads and urban areas of central Mexico. It also required the addition of an inset map showing the location within Mexico of the depicted region. The amount of data presented was a challenge to symbolize to retain legibility. Symbolizing rivers a shade of blue was a given, but balancing the remaining elements (roads, railroads, urban regions and Mexico itself) proved more challenging. Additionally, as noted for the bad example of this map provided for our course, the vein-like appearance of the rivers, roads and railroads creates a danger of Mexico looking like a lobe of a human cerebral cortex. I am not confident I have avoided this danger entirely, but an attempt was made. Again, I applied a blue data frame background and tweaked the appearance of the legend. I also altered the background of the inset map data frame to provide more contrast with the outline of Mexico while remaining subdued so as not to draw attention from the main map. Finally, the "mask" option for the labeled urban regions was essential in retaining their legibility.
The third map served as an introduction to rasters in this course and the difference between classified and stretched raster symbology. The above map depicts a stretched symbology, in which there are no discrete categories of data depicted. As seen in the legend, the data are depicted on a continuum of (theoretically) infinite gradations. A classified symbology, on the other hand, would break the topographic data into categories. A classified symbology might be more useful if the data tended to cluster at distinct intervals.
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