Creating Control Points
Creating Ground Control Points
Ground control points can be created/added in any of the following ways:
§ Create a control point at a known precise position, generally a surveyed point
§ Import a control point file with control point information
After creating a ground control point, you mark it in the relevant photos using the Control Point Editor. See "Marking Control Points in Photos" in this chapter for information.
Creating Ground Control Points at Known Coordinates
To create a ground control point at known coordinates:
1. On the Home tab, in the Add group, click the arrow under Control Points and select Create Ground Control Point. The Control Point Editor is displayed with the newly-created control point selected in the control point table at the bottom of the Editor.
Note: You can also create a control point at known coordinates from the Control Point Editor: On the Home tab of the Control Point Editor, in the Control Point group, click Add New.
2. Set the control point coordinates and properties. See "Editing Control Points" in this chapter for information.
3. Mark the control point in the relevant photos, and then save the project. See "Marking Control Points in Photos" in this chapter for information.
Creating Ground Control Points from Identifiable Locations on the Terrain
To create a ground control point from a specific location on the terrain (including LiDAR):
1. On the Home tab, in the Add group, click the arrow under Control Points and select Create Ground Control Point from Terrain.
2. Click in the 3D Window to define the control point’s location. The Control Point Editor is displayed showing a photo viewing window, a photos panel, a control point table, and a sampled photos panel - that gradually becomes populated with photo thumbnails as you mark the control point in photos.
3. Mark the control point in the relevant photos. See "Marking Control Points in Photos" in this chapter for information.
4. Modify the control point properties as required, and then save the project. See "Editing Control Points" in this chapter for information.
Creating Tie Points
Tie points can be created in either of the following ways:
§ By selecting in the Photos list the photos between which you want to establish a correspondence. The Control Point Editor opens with the Photos panel populated by the selected photos. You can also select photos after opening the Editor. See "Creating Tie Points in Selected Photos" in this chapter for information.
§ By creating a tie point from an easily identifiable location on the terrain. The Control Point Editor opens with the Photos panel populated by the photos whose frustum intersects with the created point. See "Creating Tie Points from Identifiable Locations on the Terrain" in this chapter for information.
After creating a tie point, you mark it in the relevant photos using the Control Point Editor. See "Marking Control Points in Photos" in this chapter for information.
Creating Tie Points in Selected Photos
To create a tie point in selected photos:
1. In the Project Panel, select the Photos group, and then in the Photos list, select the required photos.
2. On the Photo tab, in the Tie Point group, click Create Tie Point. The Control Point Editor is displayed with the newly-created tie point selected in the control point table at the bottom of the Editor, and with a Custom selection in the Photos panel that includes all the photos selected in the Photos list.
Note: You can also create tie points and filter the photos for sampling from the Editor itself: On the Home tab, in the Add group, click the arrow under Control Points and select Open Control Point Editor. Then on the Home tab of the Control Point Editor, in the Control Point group, click the arrow under Add New and select Add New Tie Point. See "Marking Control Points in Photos" in this chapter for information on filtering the photos for sampling.
3. Set the tie point properties. See "Editing Control Points" in this chapter for information.
4. Mark the tie point in the relevant photos, and then save the project. See "Marking Control Points in Photos" in this chapter for information. The Sampled Photos panel gradually becomes populated with photo thumbnails as you mark the tie point in photos.
Creating Tie Points from Identifiable Locations on the Terrain
To create a tie point from a specific location on the terrain:
1. On the Home tab, in the Add group, click the arrow under Control Points and select Create Tie Point from Terrain.
2. Click in the 3D Window to define the tie point’s position. The Control Point Editor is displayed with the Photos panel populated by photos whose frustum intersects with the tie point created.
3. Mark the tie point in the relevant photos. See "Marking Control Points in Photos" in this chapter for information. The Sampled Photos panel gradually becomes populated with photo thumbnails as you mark the tie point in photos.
Creating Check Points from Identifiable Locations on the Terrain
To create a check point from a specific location on the terrain (including LiDAR):
1. On the Home tab, in the Add group, click the arrow under Control Points and select Create Check Point from Terrain.
2. Click in the 3D Window to define the check point’s location. The Control Point Editor is displayed showing a photo viewing window, a photos panel, a control point table, and a sampled photos panel - that gradually becomes populated with photo thumbnails as you mark the control point in photos.
3. Mark the check point in the relevant photos. See "Marking Control Points in Photos" in this chapter for information.
4. Modify the check point properties as required, and then save the project. See "Editing Control Points" in this chapter for information.