0. The data for all of today s exercises are on-line at the following website:

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1 Geology & Geophysics REU GPS/GIS 1-day workshop handout #1: Instructions for using GPS Utility (downloading data from a GPS, displaying GPS data, overlaying GPS data on a scanned map, exporting GPS data for Google Earth and ArcGIS) GPS Utility is kind of a cool program (and it s free!). It lets you download information from a handheld GPS receiver, plot your waypoints and tracks on the screen, and even underlay a satellite image or digitized map. The full version of the program only costs $60 and if you want it is pretty quick and easy to pay and upgrade to the full version. The program (freeware version) is already installed on these computers so you can skip the parts 1-6 about downloading the program. 0. The data for all of today s exercises are on-line at the following website: The data for this portion of the tutorial are in a folder on this site called Waahila On the C: drive of the computer you are using today, create a folder called Waahila, and copy Waahila_topo03.jpg into your Waahila folder. Note, the Hawaiian word Wa ahila refers to a beneficial rain that falls in Mānoa valley and the word has an okina in it. But computers don t like okina, so we re writing it Waahila. Check out the unofficial guide to pronouncing Hawaiian words to see how Wa ahila (and Mānoa) should be pronounced. You will be using and creating a lot of files that differ only by their suffix (also called a file extension). It is important, therefore, to set up Windows Explorer so that you can see file extensions. Open Windows Explorer (the icon looks like a manila folder). If you have Windows-7, in Windows Explorer, click on Organize -> Folder and search options. You will get a Folder Options window. Click the View tab. The default is to hide extensions, so you want to un-click the box next to Hide extensions for known file types. If you have Windows-10, in Windows Explorer click the View tab, and check the box that says File name extensions I. DOWNLOADING AND INSTALLING GPS Utility 1. GPS Utility is a freeware program - you just have to agree not to re-sell it or edit it - pretty easy to comply with those conditions, I d say. Steps 1-6 of these instructions pertain to installing GPS Utility, and because it is already installed on these computers, you can skip to step 7. First get onto the web and go to the following site: 2. Click on the Download button next to where it says Download GPSU GPS Utility Version 5.23 (or whatever the latest version is). You will get an Enter name of file to save to window. Pretty much the only thing you need to decide is where you want this file saved to. To do this, in the Save in:

2 2 box, click on the little down arrow and in wherever you want to save it, double-click that particular folder. Installing on your own computer: It might be easiest to just save it to your desktop, which is usually at the very top of the list you get when you click on the little arrow. 3. Once that is all set, click the Save button and wait until the download is complete. 4. You haven t actually installed the program yet, however. What you downloaded was a group of files that includes the program and a bunch of other things, but they re not installed yet. To install the program, get into Explore. You do this by clicking the right mouse button on the Start button way down in the lower left-hand corner of the screen. Slide up and click the left mouse button on Explore. 5. You are now in the file sorting tool and depending on what version of Windows you are in it will look different. Basically, what you want to do is find the file: gpsu404setup.exe 6. Once you find this file, double-click on it and follow the typical instructions for installing a program. Say Yes to the questions that ask Yes or No, and say Accept for the questions that ask about accepting things. Eventually, you will create a subdirectory (in your Program Files directory if it is your computer and in z:\gps if you re in POST 733) called GPS Utility. Inside that subdirectory will be a file called gpsu507.exe II. STARTING GPS UTILITY 7. There are a number of ways to start the program. a) The most tedious way is to go into Explore, find the file gpsu507.exe (in the GPS Utility subdirectory), and double-click on it. b) Click the left mouse button on Start (down in the lowest left-hand corner of the screen), slide up to Programs >. Over to the right you ll see a bunch of programs. If GPS Utility is not shown, there should be a pair of double down-arrows and if you slide down to them a longer list of programs will show up. Once you find GPS Utility, hold the mouse over it and a new window will show up with about 4 things listed, one of which says GPS Utility and has a little blue and green icon. Click on it. c) The best thing to do is from the end of either steps a or b above when you finally find either gpsu507.exe or GPS Utility, right-click on it. A window will open up and one of the choices is Copy. Left-click on Copy. Then, out on the desktop somewhere that there isn t already an icon for something, click the right mouse button and the list will reappear. Left click on Paste Shortcut. The little green and blue icon with a label of GPS Utility will now be on your desktop. Now whenever you want to start the program you just double-click the left mouse button on that icon. If you are running the freeware version (on your own computer, for example), after you start the program you have to agree to their conditions by clicking Yes.

3 3 III. CONNECTING A GARMIN etrex 20 TO THE COMPUTER 8. Turn on the GPS. There is a data plug under the rubber flap on the back, and the other end is a USB connector that you attach to the computer. IV. RUNNING THE PROGRAM 9 a). Start GPS Utility. If you get the Freeware edition (a window titled License conditions for GPS Utility), click Yes. You will get the main GPS Utility window, and it will say Freeware Edition somewhere. b) In the main GPS Utility window, click GPS -> Setup. You will get an Interface Setup window. Beneath where it says GPS make/interface mode, click the dropdown button and select Garmin (USB). Click the dropdown arrow under Type/Family, and select other. Click OK. 10. Click on File -> Open. Down at the lower right, click the dropdown button and select GPX interchange file (gpx). Navigate to the GPX folder and you should see one or more files that end with.gpx. This file holds your waypoints. Click on the file and then click Open. Then click File -> Merge. Navigate to the Current folder and you should see a file called Current.gpx. This file has your trackpoints. Click on Current.gpx and then click Open. 11 a) When the downloading is pau (finished) the open window will say Untitled.txt - Waypoints[*], and there will be numbers in it. There is a column for your waypoints (ID), their position (Coordinate), what symbol they are (Symbol), two things I don t know what are (T, O), their altitude (Alt. (m)), and any comments (Comment). b) You will have downloaded all the waypoints and track points that are currently in the GPS. It is important to realize that some of these may be very far apart (more on this in section 13b below). 12. As you know, UTM is usually more useful than Latitude/Longitude, which unfortunately is the default. To switch to UTM, click on View -> Coordinate Format -> UTM/UPS. Or, up in the righthand corner there are buttons for Info. Units., Coordinate Format (you want it to say UTM/UPS (E/N), and Datum (you want it to say NAD83). To change any of these, just click the button. If NAD83 is not one of your choices, click on View -> Datum You will get a Datum Dialog window, with the Available Datums listed over on the left. To add NAD83, click the Add button and the All Datums box will become active, with lots of choices. Slide down to NAD83, click on it, and then click the button between the two boxes, which will add NAD83 to the Available Datums box. Then click Done. Make sure NAD83 is highlighted in the Available Datums box, and click OK. Once you switch to UTM, note that in the Coordinate column, you now have the zone, zone character, easting, and northing.

4 13. If you want to see a map of your GPS data, click on the map button: Or, you can click the F6 key. You now have a window titled Untitled.txt - Map, and in it are many things. There are UTM coordinates around the periphery. Your waypoints will be shown by little red symbols. The paths you took will be shown in blue, with the track points that were used to define it at the nodes. The default is to not show the actual trackpoints as symbols, but you can change the display to show them if you want (see step 14b below). There is sometimes a second blue line that defines the path you would want to follow if you wanted to retrace your path. 4 Notice that as you move the cursor around, the geographical information in a window near the top changes. You can put the cursor on one of your waypoints and compare the displayed location with that given in the Coordinate column in the text box above. You can zoom in and out by clicking on either the + or - symbols up in the upper right corner. Another way to see detail is by typing Ctrl-z (holding the Ctrl key and typing z). You get a blown-up box that has a high zoom factor. To turn it off, type Ctrl-z again. The thing with all the red arrows allows you to move up, down, left, right, etc. by clicking on one of the arrows. b) One problem that can happen is that if you have waypoints and tracks from two or more different surveys and they are far apart from each other, the program sets up a map screen that accommodates all the points. For example, you might still have points from wherever you mapped previously. To display all these points will require a map that covers a big area, especially if your field areas are on different continents!. Rarely is it useful to have a map such as this. Let s say you had points both from Mt. St. Helens and from Kīlauea. The thing to do is first save all your waypoints and tracks, regardless of where they are, into one file. Click on File - > Save. Give the file a name such as allpoints.txt Then use the File - > Save As command to save these same data to a new file name such as Mt_St_Helens.txt You can then delete all waypoints that are for Kīlauea. You are not deleting anything from the GPS receiver, only from this text file. c) Close the map that showed all the points by clicking on the X in the map s upper right corner (not the X in the upper right corner of the text file). Then redisplay the map by clicking on the map button again:. Now you should have a map of only your Mt. St. Helens data. d) But wait, what is happening??? When you click on the map icon you may still have a map that shows both the Mt. St. Helens and Kīlauea areas. That is because you probably also have track points from both places. As you know, track points are kind of like waypoints, but you don t consciously enter them. They are what the GPS uses to draw the little line showing you where you have walked. As you

5 5 can imagine there are lots more track points than there are waypoints. Track points can cause the same problems of trying to draw maps of too large an area as can waypoints. You are going to have to edit out those for places you don t want included on your map. To edit track points, you click on the button that looks like: You do the same thing as when you edit waypoints - delete those for the area you are not interested in. However, this is not as straightforward because sometimes it is difficult to figure which you need to delete. You can click on a trackpoint to get its number. You can highlight multiple track points to delete them all at once by holding the shift key while clicking on the list. To get back to the waypoint editing spreadsheet, click on: e) If you wanted, you can then make a map with the points from Kīlauea. To do this you would close everything and then re-open allpoints.txt. This time use Save As to save the file as Kilauea.txt and then delete all the waypoints and track points that deal with Mt. St. Helens. Leave allpoints.txt alone so that you can always come back to it to get what you need. f) A final thing that sometimes messes you up is if, in step 10, you downloaded the Current Position/Time. I m not sure how the GPS figures this out, especially if you are in a building, but the map tries to include it as well. To edit (get rid of it) click on: and in the spreadsheet delete the point. g) After each of these edits you need to create another map. Sometimes it refreshes on its own, but sometimes it doesn t. The simplest thing to do is close the existing map and then click on again. 14. You can change all kinds of things in the map display. To do this, click on Options -> Map Settings. You will get an Option Settings window with all kinds of choices. You can pick what to display in the Include box at left. a) One thing that is cool is to show the time that you were walking by having tic marks displayed at regular time intervals. Under the Tracks section in the Include box you will see Tics at. Click on the little arrow and slide to a time interval that you would like to display. b) To define the Track you walked, the GPS collected Track Points even when you were not saving Waypoints. You can choose to display these by clicking Points in the Tracks section of the Include box. c) You can also change the colors of the things that you display. Near the middle of the Options Settings window is a Colors box. Here it shows what colors each of the features on your map are being displayed in. To change one of them, click on the color swatch itself. You will get a Color Dialog window that shows the color being used. You can change the color by clicking on a different one. If you don t like any of the choices you can click the Edit button. You then get a Color Edit window where you can mix combinations of red, green, and blue. d) The only other thing that might be worth playing with is the thickness of the Track line, which by default is pretty thin. To do this, look in the Appearance box of the Option Settings window. You will

6 6 see Line Thickness with a window and up and down arrows. I ve found that a line thickness of 2 works pretty well. e) OK, I lied - there is one more setting to pay attention to. When it comes time to register an image to your GPS data, the more registration points you use the better. GPS Utility allows you to use up to 4. If the images you re using are not distorted you can get away with 3 or even 2, but 4 is the best, so for now, select it. You make the selection in the Map Calibration box in the lower right of the Option Settings window. f) Clean up your data. Here, you are looking for glitches caused by GPS errors. They typically look like spikes in the track point data. The way to get rid of these points is to move the mouse over the point in the map display to figure out what its number is. Then, in the spreadsheet page, click on that track point and hit the delete key on the keyboard. Again, sometimes the map refreshes and other times you have to close it and re-open it to see the result. You can also double-click on the point, and you will get a Data Dialog window (at right). Down near the bottom is a Delete Point button. Be careful, though, because there is also a Delete from Start button and a Delete to End button. These are likely not what you want to do! After deleting all the problem points, save the file. g) Make sure you have only your Waahila data (i.e., nothing from elsewhere), and save the file as Waahila01.txt V. OVERLAYING YOUR GPS DATA ON AN IMAGE OR MAP 15. One of the coolest things you can do is have your GPS data overlain onto some sort of bitmap image. This can be a digital photo, satellite image, scanned topo map, etc. But be careful - in older versions of the program, tif images caused everything to crash badly!! a) If you are using the freeware version of the program, there are two things regarding these bitmap functions to keep in: First, it doesn t allow you to change bitmaps once you have used one for a particular something.txt file. So always make sure you have a copy of something.txt without a bitmap. Use the Save As command and call the new image Waahila02.txt). That way, if you decide you want to change bitmaps, you just have to go back to Waahila01.txt, and don t have to go all the way back downloading all the waypoints from the GPS. Actually, there is a way to un-bitmap a file in the freeware version, but it is convoluted (see step 20 below).

7 7 b) The second freeware bitmap limitation is that there is a rather small file size limit to the bitmaps you can use. Finally (not related to bitmaps), the freeware version only allows you to display up to 400 trackpoints. You can ignore both these problems for now because you re running the full version. c) When you first import an image, you will notice that it won t be in the right position relative to your GPS data. This is because GPS Utility won t know anything about the geographic location of the image (it hasn t been geo-registered). In fact, GPS Utility doesn t even know that this is a map - for all it knows, it s an image of your cat! GPS Utility does know the geographic locations of your waypoints, however, so if you can relate waypoints to points in the digital map image it will then be able to correlate the two. One way to do this would be to collect waypoints at locations that you can identify in the image (points of land, tips of bays, etc.). This is easy to do with satellite images, but difficult with maps. Plus, we didn t collect any such control points, anyway. Instead, what we are going to do is create fake waypoints that correspond to the four UTM crossing points in the digital map. 16a) The first step is low-tech. On your field map, circle 4 locations where UTM lines cross. These should be spread evenly around your map (i.e., not all in one corner and not all in a line). They do not need to be at the corners. Label them NW, NE, SE, and SW. Write the easting and northing coordinates of each point in this table: Point Easting Northing NW NE SE SW b) Next you will create fake waypoints that have coordinates corresponding to these known geographic grid points. Make sure the window with the waypoints spreadsheet is active (as opposed to the window with the map). Click on the waypoint editing button:. Then in the main GPS Utility menu click on Record -> New. You will get a Data Dialog window (see right). Fill in the Easting, Northing, and ID (name) boxes, and click OK or OK and NEW. If for some reason you don t have separate boxes for Zone, Easting, and Northing, click the Multi button in the uppermost right-hand corner of the Data Dialog window. c) Repeat for the next three UTM-crossing locations. d) These new waypoints should show up in your list. If you display the map again (click on ), you ll see them.

8 8 VI. IMPORTING AND GEOREGISTERING THE DIGITAL MAP 17a) To import an image, first make sure you have a map displayed (click on ), and that it is the active window (i.e., overlying the xxx.txt window; click on the color banner along the top). In the main GPS Utility menu, click on File -> Load Bitmap You will get an Open window that allows you to search around in various disks and directories for bitmaps. Search in your Waahila folder for Waahila_topo03.jpg. Once you find it, click on it, and then click Open. Depending on what kind of bitmap you are going to use (.bmp,.jpg,.gif, etc.), you may have to change the filter. Using the Files of type: box, click on the down arrow and slide down to whatever file type you need. This file is a portion of a digital USGS 7.5-minute topo map, downloaded from the excellent Maps and Imagery collection at Hamilton Library: You could have created this image yourself by downloading the digital map from here: and using Photoshop (or a similar program) to cut out the part you want. d) The image will be displayed beneath the tracks and waypoints. You will get a window titled GPS Utility that says something about calibration. For now, just click OK. because back in step 14e you told it you would use 4 tiepoints. 18. You are going to move each of your four fake waypoints to the proper location in the digital map image. First make sure that in the map window, you can see both the first calibration waypoint you plan to move and the location in the image that it is supposed to end up at. This is important you have to be able to see both where the point is now and where it needs to go. a) Center the cursor over this first calibration waypoint you are going to use for registration and click the left mouse button. You will get a Data Dialogue window. In it will be a blow-up of the part of the image that the waypoint is in and next to this are 8 arrows pointing in various directions. The process is to click on these arrows to move the waypoint until it lies directly over the correct pixel in the image. Because the little zoom window is so small it is kind of hard to see where you are within the image, so it helps to also look in both the little zoom window and the main map window. You can go outside the little zoom window and it will redisplay. When you finally get to the right position, click OK. It is important to do this lining-up as carefully as possible because this will determine the fit between your GPS data and the image. b) Repeat the process for the next three points that you want to use for co-registration. Eventually you ll get to a point

9 9 where you have registered the two, three, or four points and after clicking OK, you have a registered version of the image and the GPS data. Cool, huh? The process would be similar if instead of a scanned map with a grid, you had a satellite image. The difference would be that there will likely not be grid lines on the image. Additionally, you would have had to save waypoints at locations in the field that you can also identify in the image. These waypoints (rather than the 4 fake ones we created in step 16) would be used for calibration. 19a) You can add text to your map. To do so, click on the Annotation button: or click Ctrl-A. Click the left mouse button somewhere in the image. You will get a Data Dialog window. In the box down at the bottom, type your text and click OK. The text will be where you initially clicked the left mouse button. If you want to move the text, click and drag with the right mouse button. At the very least, add your name. b) Save the file as Waahila_USGS.txt c) Use the zoom buttons to get to the point that you can see the whole image and your GPS data. Then (making sure the map is the active window), click File -> Save Window As. You will get a Save As window. Call the file Waahila_USGS_print.jpg (assuming this is an image you might want to include in a document) and click Save. 20a) If you mess the registration business up, it is a hassle to un-do it and go back, especially if you are using the freeware version. If you are using the full version, you can click on File -> Load Bitmap, and in the Map Calibration Dialog window, you select (No Bitmap) and click OK. However, if you try to re-load a bitmap that you ve screwed up the tiepoints for, it will try to use the same screwed up tiepoints, and not improve anything. If this happens, skip to step 20c. b) If you are using the freeware version, you don t even get the opportunity to go back to the no bitmap situation, and again, that is why you saved a version that had no bitmap. So what to do, what to do? The trick is the fact that GPS Utility files are have a.txt suffix, and can therefore be opened and edited in Notepad. c) If you have to un-do the registration, close GPS Utility. Open Notepad, and open Waahila_USGS.txt Scroll to the bottom and you ll see a line that says something like: S Image=Waahila_topo03.jpg Delete this line and everything below it. Save the file and close Notepad. You ll be back at the pre-bitmap-importing step (17).

10 10 VII. VIEWING GPS DATA IN GOOGLE EARTH Google Earth is a good source of high-quality, high spatial-resolution data. You can import GPS data into Google Earth, but you re stuck with Google Earth s annotations, colors, and symbols. 21. All you have to do is save this file in a format that Google Earth can read. In GPS Utility, Click File -> Save As You will get a Save As window. Down at the bottom is a Save as type box with a drop-down arrow. Click the arrow and select Google Earth (kml). Call the file Waahila_Google.kml, and click OK. 22. Open Windows Explorer and double-click on Waahila_Google.kml. Google Earth will fire up and you will be taken to your field site. Pretty darned cool, actually. You can send this.kml file as an attachment, and someone with Google Earth installed can double-click the attachment and it will launch Google Earth and navigate right to that place. VIII. EXPORTING DATA FROM GPS UTILITY TO ARCGIS 23. Close the map window. If you want things to look a little cleaner, delete the 4 geographic groundcontrol waypoints (nw, ne, se, and sw), and save your file as (click on File -> Save As ) Waahila03.txt b) GPS Utility allows you to save tracks and waypoints directly as ArcGIS shape files. To do this, (in GPS Utility), click on File -> Save As You will get a Save As window, and you are going to need these files to be in your Waahila directory. c) In the Save as type: box, click the dropdown arrow and select Shape trackpoint fileset (shp + shx.dbf) Call the file Waahila_trackpoints.shp and click Save. If you look in Windows Explorer, you ll see that GPS Utility created 3 files: Waahila_trackpoints.shp, Waahila_trackpoints.dbf, Waahila_trackpoints.shx. d) Repeat steps 1c, but this time in the Save as type: box, click the dropdown arrow and select DBF waypoint fileset (shp + shx.dbf) Call the file Waahila_waypoints.dbf and click Save. Again, a check of Windows Explorer will show that 3 files were created: Waahila_waypoints.shp, Waahila_waypoints.dbf, and Waahila_waypoints.shx. All is fine except that if you were to import Waahila_waypoints in ArcGIS you would see that it is actually your waypoints and trackpoints. Kind of humbug. 24. Because the native file format for GPS Utility is an ascii text file, it can be opened in a variety of programs, including Excel. You are going to edit the file in Excel to make it easier to import into ArcGIS.

11 11 a) Close GPS Utility and open Microsoft Excel. Click on File -> Open and navigate to your Waahila folder. In the lower right of the Open window, you ll see a drop-down button. Click it and select Text Files (*.prn; *.txt; *.csv). You should then see some text files in the largest box. Select Waahila03.txt and click open. b) You will get a Text Import Wizard Step 1 of 3 window. Select the Delimited button and un-select the Fixed width button, and click Next >. c) You will be in the Text Import Wizard Step 2 of 3 window. In the Delimiters section, un-check Tab and select Space. In the Data preview box, slide down a little ways and make sure that your data will be delimited properly, namely that you ll have columns for ID, Zone (Zne), Easting (Eastng), etc. It should look like this: d) Click Finish (you don t need to go on to step 3). 25. You will be in a standard Excel window, and all you need to do now is a bit of editing. a) First, delete everything in rows You can delete the rows themselves as well, but it doesn t matter they have to at least be blank. b) Next, scroll down to where the waypoints end and the trackpoints begin. There will be a blank row and then column B will say TRACK and column C will say SUMMARY. Delete this row and all rows below. c) Next, delete columns A, C, F, G, H, I, J, and K. In this case you need to delete the columns entirely, not just blank them out. You will have 3 columns remaining. d) Change the headings of the 3 remaining columns to: name, easting, and northing e) Click File -> Save As. You will get a Save As window, and make sure that the Save as type: box says Text (Tab delimited) (*.txt). Name your file Waahila04.txt and click Save. Excel will warn you that some features might be lost, but say Yes anyway. Close Excel. When it asks you if you want to change changes, say No. Once this is finished, close GPS Utility and Excel and go on to the next handout.