Land/Air allows you to use images or bitmaps as valid maps. In this way you can complement your maps downloaded from the Internet with other paper maps you have scanned yourself.
Scanning a map can often be a long and tiresome affair; the size of a map usually implies that you have to scan it bit by bit or take it to a specialized establishment. This is why we recommend that, whenever possible, you obtain your maps from the Internet or the CompeGPS CD maps.
Nevertheless, if you do have a scanned map, once you have digitalized it you will have to calibrate it for use with Land/Air. As we have already mentioned, you do need to know the exact coordinates of at least 2 or 3 points on the map. To calibrate a map, follow these steps:
1. Select the menu option ‘Maps > Calibrate a Bitmap’. A new window will open.
2. Select the map you want to calibrate and Click on the button ‘Open’. Land/Air allows you to work with these formats: *.JPG, *.PNG and *.BMP.
Land/Air opens the file on the main window. You can zoom, scroll… on this map but you will not be able to do anything else because it is not a calibrated map. On the lower part of the screen you will find a new section with four labels. Each label will have to be filled in with real information about the map you have opened.
3. In the first label: fill in the information about projection and datum and click on the button ‘Next’.
NOTE: If you do not know the projection of your map, establish the automatic option. Land/Air will use the U.T.M. projection system, most adequate since it is one of the most extensively used.
4. Click on ‘Next’ or ‘Frame’ and select the area of the map that you want to appear on screen if you have more than one map loaded. This operation is useful to adjust the map in the best way to make working with other maps easier. In a general way, this operation is used to eliminate the frame that surrounds a map so that it fit perfectly alongside another map.
5. Click on ‘Next’ or on the Point1 label and write the coordinates of this point, its area and its projection:
•X, Y: click on the first point of the map that you want to act as calibration point 1. The images coordinates will be established (data in pixels).
•Type of coordinates: Select the type of coordinates that are used by the point and write it (X Y, Lat/Long...)
If you introduce a point in a written in a different projection to the projection that you selected for your map (you did this in the first label), then these coordinates will automatically be converted into the selected projection the moment you change the label. Using the different window functions, you will be able to move a point from one place to another, to view a point (centre it on the screen), eliminate a point, or use a waypoint as a calibration point.
6. Click on ‘Next’ or on the point 2 label to fill in the necessary information about this point. We recommend that you use a minimum of three calibration points in order to obtain an accurate calibration of the map. To include the third calibration point click on Add addition point and a new label will appear, called Point 3; fill in the necessary information in the same way as with the other points. You can introduce as many points as you wish, although only 3 are really necessary.
7. Lastly, you have to store the calibrated map in the predetermined directory, in *.IMP format. You can name it as you wish, or you can keep the original name, and then click on ’Save’.