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From: Evan Dallas <evand_at_prghr.com>
subject: [Paddlewise] Using Google Earth to get list of GPS waypoints
Date: Fri, 23 Mar 2007 13:05:12 -0700
I wrote the following "How to" for posting to my club's website, and 
thought it might be useful to some Paddlewisers as well.  This is really 
a dual purpose "How to": (1) How to use the free Google Earth ("GE") 
software to create a set of Placemarks (like when planning a kayak 
trip), and (2) how to extract the latitude and longitude for those 
Placemarks into a list.

As anyone who uses a GPS much knows, getting the waypoints from the 
chart into your GPS is probably the most laborious part.  There are 
several commercial software packages that allow you to create a list of 
waypoints by just pointing and clicking, but they are fairly expensive 
and limited to the geographic area you purchased.  I just discovered the 
second part of this "How to" regarding using "GE" to compile a list.  
Note that this "How to" assumes familiarity with GE and Excel and a 
moderate (but not advanced) amount of computer skill.

1. Start up GE

2. Enable sidebar: Make sure the sidebar is displayed. If not, type 
<Ctrl><Alt>B (or go to "Tools" and click on "Sidebar") to enable it.

3. Create folder: Create a new folder to hold your waypoints (note that 
GE calls these "Placemarks" - for the purpose of this post, they are the 
same thing) as follows:
    a. Within the "Places" section on the sidebar, single click on "My 
Places" to highlight it
    b. Then type <Ctrl><shift>N to add a new folder and give it a name 
of your choosing.
    c. Once created, the new folder should be highlighted.  If not, 
single click on it to highlight it.  This will cause all the 
waypoints/placemarks you create to be stored in this folder.

4. Adding waypoints: Now comes the fun part --
    a.  Zoom in on your area of interest (I usually start from the top 
and work my way south) and get it roughly centered on your screen.
    b.  Either use the menu ("Add"/"Placemark...") or the shortcut 
(<Ctrl><shift>P) to create an initial waypoint, then "drag" it with your 
mouse to the exact location you want.  Be sure you've taken advantage of 
the zoom to get up close so you can place it exactly where you want it.
    c.  The default "Placemark" symbol is a thumbtack, but to me this 
symbol is too large and clutters up the map.  Change it to something 
smaller by clicking on the thumbtack icon on the "Add placemark" menu 
(as opposed to the thumbtack on the map).  This will open up a large 
group of symbols you can substitute.  Once you've chosen a particular 
symbol, it will become the default for future placemarks.
    d.  Under "Name" on the "Add placemark" menu, type in your 
description.  I find it useful to include a word for the type of 
waypoint, for example "Camp - Paradise cove" or "Hazard - Typhoon tidal 
rapids".
    e.  If you really want to get into it, you can easily color code the 
text. I use one color for camps, another for landmarks, and another for 
warnings.

5. When you've added all the waypoints/placemarks you want, make sure 
they are all in the folder you created in step 3.  If not, you can drag 
and drop them into the folder.  You can also reorder the symbols this 
way, ie "dragging" a symbol within the folder up or down to get it in 
the order you want.

6. At this point, you will have a set of placemarks that you can archive 
for future trips, dazzle your paddling buddies by emailing the 
placemarks to them (right click the folder, then choose "email..."), 
-or- save to your computer in a way that lets you extract the GPS data. 
When you email the folder to someone, assuming they have GE installed, 
generally all they need to do is double click on your attachment, and GE 
will automatically launch and zoom in on the places you've marked.

7. To get the placemarks into a format where you can extract the 
latitude/longitude data:
    a.  Right click on the placemark folder.
    b.  Choose "Save as...", then on the "Save file" menu that pops up, 
change the file type from the default (which is *.kmz) to *.kml. GE's 
"kml" file format is essentially an xml file format and can be opened up 
in a variety of ways, but for our purposes, the easiest tool is probably 
Microsoft Excel.
    c.  Once you've changed the file format to "*.kml", then save the 
file in some convenient place on your computer.

8. Although the default software to open a kml file is Google Earth (so 
_don't_ just double click it), as mentioned above you want to open it 
with Excel instead. Probably the easiest way to do this is to start 
Excel, then under Excel's File/Open command, navigate to the place you 
stored your *.kml placemark file and open it up.  (Within the Excel 
"File open" option, under "File types" be sure to specify "All files" or 
the kml file won't show up.)  It will open in a read-only mode, but you 
can still copy data from it.

9. GE stores a LOT of information in this kml file, but the key data you 
probably want is just the waypoint description in column O (the letter 
O, not zero), the latitude (in column G), and the longitude (in column 
I).  (It also stores altitude, which I suppose could be useful for 
someone using this technique for backpacking or climbing).  What works 
easiest for me is to have a separate Excel spreadsheet open at the same 
time as the kml file, then to just copy the relevant columns one at a 
time from the kml file to your other Excel file.  Since my waypoint 
descriptions are always much more than 6 characters (the maximum 
waypoint name length on my GPS), I paste them into the "Comment" field 
of my GPS input file layout.

10. Note that the GE-generated latitudes and longitudes will be based on 
the WGS84 map datum, so when you enter this data into your GPS, your GPS 
should be set to that datum. Once the data is input, you can of course 
set your GPS datum to whatever datum you prefer.  For example, if you're 
using a nautical chart that uses the NAD27 datum, switching your GPS 
(_after_ you've entered your new waypoints) to that datum will 
automatically reconfigure your waypoints from WGS84 to NAD27, but still 
"point" to exactly the same locations.

11. GE stores waypoints using the international convention where 
northern hemisphere latitudes and the eastern hemisphere longitudes are 
positive numbers (rather than N and S), and southern latitudes and 
western longitudes use negative numbers (rather than E and W).  My GPS 
software didn't have any problem with this.

11. Getting the waypoint data from your spreadsheet into your GPS is up 
to you and "beyond the scope" of this how-to.  I use the free software 
"GPS utility" (http://www.gpsu.co.uk/), a product similar to 
OziExplorer, which uses plain text files for uploading data into a GPS. 
It took me about an hour of monkeying with Excel to get it to produce a 
text output file with all the waypoint data properly formatted for 
direct upload into GPS Utility.  So now, all I need to do is paste in 
the GE columns of placenames, latitudes and longitudes from the kml file 
into my spreadsheet, manually key in a 6 character shortened name, and 
then write out the text file for input into GPS Utility, which easily 
uploads to my GPS.  That may still sound like a hassle, but it's much 
quicker (and less error-prone) than keying in all that data.

I may regret saying this, but I'll be happy to email my spreadsheet to 
anyone who is interested.  Just send me an emailed request off-list.  
***Be sure to include "Paddlewise" in your subject line, or your email 
will end up in my spam bucket!*** I'll probably wait 2-3 days, then send 
it in one batch email to anyone interested.  Note that if you don't use 
GPS Utility, this spreadsheet may not be useful to you.

Evan Dallas
Woodinville, Washington
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