Geog 417 - Advanced GIS

Lab 1


This is the dreaded GPS lab! Your task will be to get familiar with the Garmin ETrex GPS recievers - for collecting, downloading, importing, and mapping point data.

FINALLY, we won't have to use goofy freeware programs to get the data off the GPSs and into Arc.

You will require for this lab - a gps reciever (Garmin eTrex 10), lab printout, and a field notebook of some sort.

Remember that the first thing you do with a GPS is clear the memory (waypoint manager, hit menu, and delete all) and make sure the coordinate system and datum are set properly (for this lab, use UTM UPS, meters, WGS 84 datum, and the WGS map spheroid. Goto setup - position format)

The tasks:

  1. Map either outdoor sculptures or class treees around campus. Store them as a series of waypoints. In your field notebook, write down the x,y coordinates (this is your backup and reference) and the name/date of the tree/sculpture. Get at least a 6 trees and/or sculptures.
  2. Hike the Ganges across campus, collecting waypoints every few steps. Remember, your reciever can only store 1000 waypoints!
  3. Answer the question - what is at each of the following points (assume UTM, meters, NAD27): NAD27 for this question ONLY. Yup, this means you will have to go in and reset your gps. Then set it back when done with this question.
    1. E 0686943, N 5208246
    2. E 0687063, N 5208312
    3. E 0687194, N 5208314
    4. E 0687112, N 5208217
  4. Pick somewhere on campus (describe the location). What are it's UTM coordinates in the following Datums: NAD27, NAD83, WGS84 (write them down, don't store them)? What is the range of x and y values? What is the difference (in meters) between each pair? Having done this, answer the following question - why is setting your datum important?

OK - now you have a bunch of points stored in your GPS. Time to get them into ArcGIS.

First, you need to use the computer in the GIS lab which is next to the printer - it's the only one with a download cable. Please... leave the cable there. It's the short, little USB cable.

Plug your gps in. Wait. Eventually, the computer will recognize the gps as another harddrive. Go into the garmin/gpx folder and grab your waypoints file (it will be a .gpx file. Copy it to your flash drive.

Make sure everything is in the same subdirectory on your flash drive. This makes life simpler when playing in Arc.

NOTE: whenever you are mucking with files as much as in this lab, save EVERY one with a different filename. Then if you screw something up, you don't have to go back out and recollect all the data - you just back up one step.

Just for fun, fire up Google Earth Pro. File, open, gps format, and navigate to your file. Let's see if it shows up in the right place.

Question 5: How did GE do with this file? Everything in the right place?

Fire up arc. Go into toolbox and use the conversion tool gpx to features. You should now have a point shapefile. Note. this didn't work for me the first time. But it did the second.....

Note, if you want to seperate out some of your data, select it and do a data - export data to get a new shapefile with only your selected data in it.

Now, open ArcMap and add that image you grabbed from the data drive. Make me a pretty map with a nice background map of some sort. Include your 2 coverages (ganges and sculptures/trees) on top. Label the sculptures/trees. Make it look reasonably nice. Print out this map.

Hand in - answers to questions 3 - 5 and your final map.

Due date: Worth 3 points.

NOTE!!!!! Be sure you report all you answers using proper significant figures. In this and all future labs. If you're not sure how significant figures work, watch the video posted to this class's main page..