- HOW TO CREATE A RING AROUND A POINT IN MAPINFO 10 HOW TO
- HOW TO CREATE A RING AROUND A POINT IN MAPINFO 10 DOWNLOAD
The more you have the precision should be greater. There is no rule how many point you should pick. I picked couple of points around lake Colac and his friend. Repeat this procedure for more points (you can also easily remove or move points if you made mistake). Also the more points you will add the table below the image will fill with more rows. Now you should have two small red dots both on your map and your scan image saying: “look, the point on the scan is the same point on the map”. Now click ‘From map canvas’ and select the same point on your map. Picke some characteristic point on the lake shore which you can easily find on your map canvas. You will be adding points (GCP-Ground Control Points) connecting your scan to geographic environment. You will have to spot the same shapes of the bays, shore in other cases crossroads, river banks etc. Zoom in to the Colac lake on the scan and set also Colac lake on your map canvas. Now what we are going to do is to find similar features on the scan and on our map canvas. Load your scanned map clicking the ‘+’ button in top left corner. Delete the raster layer, use again Zoom to Layer but this time on the lake Colac layer and open the Georeferencer from the Raster menu on top. We have to use a tool which will transform image coordinates to the map coordinates. No wonder that the scan is totally in the other part of the World than lake Colac. This is totally different numbers range than coordinates which we should expect in our project. Now you can see your scan but look on the coordinates (bottom of the map screen). Your project and Colac lake shapefile have set coordinates (EPSG 20354) but your scanned map is still in its own coordinate system – the image coordinate system.Ĭlick the right button on your scanned map in the layers menu and select Zoom to Layer option. What happened? You can’t see the map? Why?īecause it is in the other part of the World. Now add the shotpoints map to your project clicking Add Layer and then Add Raster Layer. It is here and proper coordinate system (CRS) is already set up (as it is the first sapefile in the project – CRS is loaded to project automatically). Let’s open the empty project and add vector layer with Colac lake to the map canvas. Now let’s continue with our shotpoint map.Īlso from the previous excercise we have shapefile with lake Colac in proper coordinate system which is AMG zone 54 (EPSG 20354). This method strongly depends on the abilities of operator, cartographer.
It is quick and sometimes you can’t substitute it with other possibility but sometimes the accuracy might be its biggest disadvantage. This method requires good eyes and good shape recognition as it is based on comparing of the geographic features on two pictures. Or in other case you would like to append to your project scan or not registered aerial photo of some place.
HOW TO CREATE A RING AROUND A POINT IN MAPINFO 10 DOWNLOAD
Sometimes you might happen to just download very schematic map or just a sketch of some area. It is especially useful when you do not have any grid, graticules or coordinates on your map.
Now we are going to use this file in georeferencing of our scanned shotpoint map.
HOW TO CREATE A RING AROUND A POINT IN MAPINFO 10 HOW TO
How to georeference scanned image in QGIS and vectorize items from OpenStreetMap-part 1. Welcome! In the last part we succesfully downloaded vector data from OpenStreetMap.
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