Terrain Analysis with GRASS 6.4.1. Test at Smith-9th Street

Visibility Analysis at Smith-9th Street Station -  The pink X is the location of the Smith-9th Street Station and the Red Circle is the location of the Williamburgh Bank Building shown in the picture above.  The dark green areas are areas at street level that are visible from the station.

  In he map above, I added the street grid.  The green area (non-neon) is the area produced by GRASS 6.4.1. in the Terrain Analysis Mode - Visibility Option for the Smith-9th Street station (pink x).  The elevation that I gave for the station was 90 feet.  GRASS 6.4.1 studied the elevation file (neon green color) and calculated the visibility to street level of an observer from the Smith-9th Street elevated station on the F line.  Since I added a street grid, I was able to locate the location of the Williamburgh Saving Bank building which is the the large sandstone pointed building in the center of the picture above obtained from the web.  The bank is indicated by a red circle.  The red circle is near the edge of the green visibility area.   In the photograph above, you can see that it appears on the edge of the viewing area.  If you look above and follow the F train route to the south and west, you can see that the F train splits up (right triangle) near Prospect Park.  Notice that the green area ends at Prospect Park West.  The elevation is very high there and you can see why a person standing at Smith-9th Street station looking west on 9th Street could not see much beyond the park.  The Smith-9th Street is currently going under rehab and it would be interesting to see when the station opens if this analysis is accurate.