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Tips and Tricks
 
 
  GPS in forest
  Use Popup menu
  Add cordinates on your printed maps
  Create your tracks with comments and details
  Enter a destination with a simple road map
  Save your course
  How accurate is your GPS now
  Scan your map with a camera
   
 
   
GPS in forest    

You probably noticed, the GPS loses itself much more in forest that in a clear sky. In forest, the communication with the satellites is constantly stopped by non homogeneity of the vegetation and mountains.
That disturbs the GPS during displacements because it must have a permanent contact with each acquired satellite.(the satellite menu bar is changing from Gray to black) during more than one second to record a complete signal.
If the acquired satellite is not visible any more, the GPS simulates its position.
In this manner it will be able to record a complete signal even if it has the communication only a few seconds.

There are three things to do to increase the effectiveness of the GPS in forest.

Turn on the GPS 15 to 20 minutes in a clear sky view before going or during the way in the car to keep the time for the gps to acquire all the satellites available.

Do not turn off the GPS after point 1 and put it in a high place, for example on the top of the back bag to let the GPS having the more clear view as possible without the shadow of the body.
If it is not possible, there is always the possibility to buy an antenna.

Place the GPS on a stable place on the ground each time it's possible so that it can be synchronized without moving with the avaiable satellites.

I made trips during several hours in the tropical forest in this way and I had preserved my GPS functional during all the trip.

  
   
Use Popup menu  
Popup menu are accessed simply by right click with your mouse at many
places in Cartopro. (Windows, Buttons etc)

Try it everywhere in Cartopro, many features are not accessible otherwise. 		 
   
Add cordinates on your printed maps  
 

Print your map with U.T.M. coordinates and Datum WGS 84 and set your GPS with the same parameters.

The printed grid is graduated 1 by 1 km (1000 m ) on Cartopro and the coordinates wrote on the margin are growing to North and East.

You can display this same coordinates on any GPS, they will be displayed on metter.
In this maner, the coordinates wrote on the map are des same as those wrote on your GPS minus 3 digits.The 3 more digits represent the relative position inside the square like in the picture.

  
     
   
     
  To select the right Units and Datum for printing:  
 
- Choose U.T.M. coordinates on stretch window.
  
 
- Go to menu Calibration, Change the Datum used...
  
 
- Select WGS 84
  
 
- Click OK
 
 
- Display the grid by the menu Grid, Displaying
  
- Finally print your map by click on File, Print
  
   
Create your tracks with comments and details  

The goal is to put a maximum of useful information on your GPS to get it more easy to read on site.
To do that, create a track and add to it all crossing and possible ways with comments for each particular point. See exemple below




See help on Track Editor to find how ...

  
   
Enter a destination with a simple road map  
U.T.M coordinates are very useful with a GPS beacause North and East units are expressed in metre.
It is then possible to point a relative position from our actual place on any map if we know the scale.
One exemple with a 100'000 scaled map, the width of the thumb on the map is aproximatively 2.5 [cm] then 2'500 meters on the ground. (1 [cm] = 1000 [m] ).
Note the coordinate where you are on the map. (Read them on the GPS)
After that add the meters North and East to your actual U.T.M. position to represent the destination point you have chose on the map.
Now push 2 seconds the "mark" button on your GPS and replace the coordinates of the new recoorded point by which you just calculated.
Now select Goto and the GPS will guide you through your destination.
I made some trips using this trick and I found my destination with a margin of 100 meters.		  
   
Save your course  
Use the track log to save your travel. In this maner you will be able to comme back on your traces by reading the path on your GPS.
Do not forget to stop recording when going backward to not erasing your track log.
In many GPS, it is possible to store your track log in memory. The saved track will be displayed larger and then will be more visible.
If your track log is saved on memory, you can erease it and continu to store your travel.
On the road, presse time to time the mark button to store waypoints. This will give you some references about where you are when coming back.		  
   
How accurate is your GPS now  
The Accuracy is noted on the satellite page of your GPS. Usually, the GPS accuracy is about 10 m horizontally and 15 vertically.
It can be degraded in forest or if part of the landscape is masked by mountain for example.
You have to know the accuracy of your GPS at the time you use it and then you must take a look to the satellite graphs.
For a good performence, your GPS must have more than 3 satellites monitored, about 6 would be find.
If not, your GPS risk to loose his position at the first obstruction of a satellite view. 		 
   
Scan your map with a camera  
On vacancy, we need to make things with what you have.
Here is a map (with its calibration) which I photographed with my NIKON CoolPix 5000.
The photograph is taken upright, in the center of the map.
The map was positioned on floor, carefully smoothed. Four heavy objects maintain it tended and flat.
Click on the downloaded file CartePhotoNum.exe and choose the map folder of Cartopro to install it.
After having opened the map, display the U.T.M. Grid   to see the very weak errors of calibration. Quality was verified on mountain bike with the GPS on the ground.

Note:
The bad quality of the colors is due to the reduction of the number of color by PhotoShop. Cartopro required an image 256 colors.
The current version of Cartopro automatically makes this conversion under condition optimal. Brightnesses are due to the flash... 		 
     
     
     
     
     
     
     
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  
Create modify and save routes, tracks and waypoints by simple clicks on screen
Cartopro works with any scanned map
Transfer your data easily between your PC and your GPS using RS 232 or USB
Compatible with Garmin and Magellan eXplorist