USGS 1:24,000 topographical maps are now selectable from View, Map Type, Topo. Topo maps can be zoomed from 4m/pixel to 32m/pixel. (Normally USGS DRG maps are about 2.5m/pixel). They will match-up going from topo to photo, but not necessarily from photo to topo because each 4m/pixel topo image is 4 times wider and higher than a 1m/pixel photo zoomed to 4m/pixel.
COLOR PHOTO MAPS:
These maps (which have four times the resolution as the black and white maps) are avialable by selecting: View, Map Type, Urban Areas. Then just do: File, Download Map Data, Fill Screen. Page Up/Down selects 2.0, 1.0, 0.5, or 0.25 meters-per-pixel resolution. NOTE: These maps are available in only a few select areas of the US, Washington, DC, Houston, Atlanta, and Chicago for now. See (HERE) for a test of the accuracy of these maps. However, see (HERE) for a registration error in the color map of the Houston, TX area and the error in an Atlanta topo map.
DISPLAYING TOPO CONTOUR LINES ON THE
Obtaining data for the contour lines isn't 'automatic' as with the photo and topo maps. First one must go to ConvertSDTSData 1.0, then download and extract the files to the USAPhoto directory -which produces ConvertSDTSData.exe. See (HERE) for an example of the contour lines (green lowest, yellow/orange highest).
Obtaining DEM Data:
1. On a photo screen, press X. The bottom coordinates are the coordinates of the needed DEM data.
2. Access http://188.8.131.52/SDTS_DL_b.htm and enter these coordinates.
3. Download the 30m x 30m DEM data to the USAPhoto directory. (This covers an area 7 1/2' Lat/Long 'square')
4. Run ConvertSDTSData.exe
5. Re-boot USAPhoto.
6. By pressing C, the contour lines should appear on the photo maps, color coded as to altitude.
7. Repeat for any other photo screen without contour lines.
Placing the cursor on these enhanced maps shows the elevation of the cursor.
You can compare these contour lines with Magellan MapSend, Garmin, and the USGS Topo lines (HERE).
Zooming photos out past 8m/pixel to 16, 32, or 64m/pixel accesses a different database, requiring more map downloading. In File, Preferences, Everything Else, is an option: -Use 1-meter photos to display 8-meter zoom level in addition to downloaded 8-meter photos (or 'not' -to avoid one step). When you select File -Download Map Data on the Menu bar, 1 meter/pixel photos will be downloaded if the zoom level is 1 thru 8, and 8m/pixel photos will be downloaded if the zoom level is 8 thru 64.
Topo maps can be zoomed only from 4m/pixel to 32m/pixel; however, switching from photo to topo maps automatically corrects to the allowed zoom level. Photo contour lines, if present, will increase accuracy as the photos are zoomed closer.
Panning will also expose new squares to be downloaded. Once downloaded, the map data will be seamlessly connected together and stored on the computer HD -never having to be downloaded again. When running the cursor over the map, its coordinates are shown at the top. Select: View, Lat/Lon, and the displayed coordinates can be set to: D, DM, DMS, or UTM.
NOTE: Use Ctrl-PageUp or Ctrl-PageDown to center the map at the cursor position.
DOWNLOADING WAYPOINTS TO THE MAP:
Setup: Select: GPS, and set Comm Port, Protocol, and Baud. Set the unit to the Garmin mode.
From: GPS, Waypoints, press Receive. Waypoints will be downloaded and displayed on the map as green dots. Right-click on the dots to read the name and comments. To list the waypoints, select: Waypoints, List. These waypoints can be sorted either by Name or Comment. They can also be edited, lines & distance drawn to them, deleted, or GOTO. GoTo is a convenient way to create a new map, because a distant (but in the same UTM zone) GoTo will re-center the blank map to the waypoint where the aerial photos can then be filled in. With Ver. 2.04.7, one can now adjust the waypoint dot sizes on the various photo or topo zoom levels.
NOTE: Only waypoints within the UTM zone of the map will be displayed and listed. Once a New Map is created in a different zone, then the waypoints downloaded from the GPS unit in that zone will be listed. Also, note that waypoints are stored in the *.xml files.
Select: GPS, Tracks, Receive. After giving the track a name, it will be downloaded to a FILE. To display this (or any other) track, select: GPS, Tracks, Display. Tracks downloaded to a map will automatically center the map to the track.
USAPhotoMaps can also be used to show your position on the maps in real time. Place the Garmin unit in the Garmin mode and select: GPS, Show Location. A cookie trail of up to one hour of blue dots will appear and will not disappear when they scroll off the screen.
1 meter per pixel, Show-Position Track on Aerial Photo map (same area as topo map, above)
Track made while driving around the perimeter of a shopping center parking lot. The green dots are waypoints, the eastern-most one being a survey station where the coordinates are known to within centimeters. While moving, the closest APPROACHING waypoint is displayed on the title bar.
In File, Preferences, are the options: Colors (adjust), Waypoint dots (sizes), and "Everything Else" -which is: (1) Use 1-meter photos..... (normally not checked), (2) Set the existing screen and zoom as the opening screen. (3) Sort waypoints initially by Name instead of by Comments (usually checked), (4) Show current Lat/Long instead of nearest approaching waypoint.... (usually not checked), (5) Show nearest waypoint Name instead of Comment... (usually checked).
FUN WITH ROUTES:
By using either a Garmin GPS-V or StreetPilot-III (placed in the simulator mode), one can display the simulation of driving stored routes on the USAPhotoMap maps. The display is almost like watching a movie! The track dots start out slowly following the small streets and then picked up speed as the speed classification of the various reads increases -always showing the closest approaching waypoint in the Title Bar.
Pressing "Q" and then running the cursor over the map will expose the row name of the 200-meter square maps, but not the column name, for example z16y18827 where 16 is the zone and 18827 is Northing divided by 200. This information is helpful if ever one has some rows of maps that are corrupted. Simply go into the "usaphotomapsdata" subdirectory and delete the same-named files. The size of these files is determined by how many squares have been downloaded to the row.
The row and column name of the center of the named map is explained in the Help, Advanced file, and can be used to fine-tune map coordinates in the USAPhotoMaps.ini file. For example: Atlanta&X=3709&Y=18764&Z=16 where the numbers are Easting and Northing divided by 200, and the Zone. Tracks are stored in *.csv files -which can be viewed by Excel, and Waypoints are stored in *.xml files which can be viewed by Internet Explorer. By opening the Elev.ini file, one can read the names of the 7 1/2' quadrangles containing the DEM data downloaded for the photo contour lines.
This program has been tested with a G-12XL, GPS-III+, GPS-V, GPSmap 76(S), and Vista.