The box at the top of the dialog box lists all control points that have been assigned to the raster image. Each control point has a label, indicating the name of the control point. The label is optional; if you do not specify a label, MapInfo Pro assigns a default label, such as Pt 1.
To enter a control point, choose the New button, then click on the image preview in the lower half of the dialog box, at a location in the map image where you know the map coordinates. When you click on the image, MapInfo Pro displays the Add Control Point dialog box (described below).
Once you have entered several control points, MapInfo Pro displays an error calculation for each control point. An error value of zero indicates that the control point is placed correctly. An error value greater than zero indicates that the control point's placement seems incorrect, given the placement of the other control points. The numeric error code indicates the control point's distance, in pixels, from where MapInfo Pro calculates the control point should be placed.
Edit
The Edit button is enabled when you choose a control point from the Control Points list. Choose the Edit button to display the Edit Control Point dialog box. Use this dialog box to edit the name, map coordinates, or raster image coordinates of the selected control point. For a description of this dialog box, see below.
Remove
The Remove button is enabled when you choose a control point from the Control Points list. Choose the Remove button to delete the selected control point.
Find Button
Use the Find button to locate control points in the image in the Image Registration dialog box. Highlight the control point entry in the list and click Find. The image redraws to include the control point you specified.
Add
The Add button is always enabled. Clicking the Add button deselects the currently selected control point. If no control point is currently selected, clicking the Add button has no effect. Remember to click the Add button before you add new control points. If a control point is selected, and you forget to click the Add button, and you click on the image preview, you will not be adding a new control point, you will be editing the selected control point.
Pick from Map Button
Use the Pick from Map button to select control point coordinates from the map for the selected raster image. Click the Add button, then click the Pick from Map button to select the X and Y map coordinate from the Map window.
+ Button, - Button
Choose + to get a closer look at the raster image. Choose - to zoom back out.
Units
Choose the Units button to set the coordinate units you want to use when entering control points. When you choose Units, MapInfo Pro displays a dialog box with a list of coordinate units. The list of available units depends on the map projection you are using. For example, if you have specified a Lambert map projection, the Units dialog box lets you choose between degrees longitude/latitude and meters (the unit of measure normally associated with Lambert maps).
Projection
Choose the Projection button to tell MapInfo Pro which map projection is represented by the raster image. When registering raster files, the projection is initialized to Default Table projection.
OK
When you choose OK, MapInfo Pro stores the raster image's registration information (control points, coordinate units, and map projection) in a table file.
Cancel
The effect of the Cancel button depends on existing conditions. If you are opening a raster image file for the first time, and you choose Cancel from the Image Registration dialog box, the file is not opened. You must complete the Raster Image Registration dialog box before you can display a raster image in MapInfo Pro.
After a raster image has been registered, you can return to the Image Registration dialog box by on the TABLE tab, in the Maintenance group, click Raster, and Modify Image Registration. At that point, choosing Cancel cancels any changes you made in the dialog box; however, the raster table remains open.
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