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Georeferencing Control Points Context Menu

Commands available when right-clicking Georeferencing Control Points (also called tie points or ground control points) in the Data Tree. Control points are pairs of corresponding positions - one in the model/image space and one in real-world coordinates - used to establish spatial reference and alignment between datasets.

Menu name: Navigate To Tooltip Move the 3D view to the control point location.

What it does See Navigate To in Shared Commands for complete documentation. Centres and zooms the 3D view on the selected control point's position, allowing inspection of its location relative to model geometry or imagery.

When to use it

  • Verifying control point placement
  • Reviewing control point distribution
  • Checking alignment at specific locations
  • Navigating between control points for quality control

Notes View centres on the source position (model/image coordinates). For tie points linking two datasets, this shows the position in the primary/source dataset.

Position Management​

Copy Position​

Menu name: Copy Position Tooltip Copy control point position to clipboard.

What it does Copies the control point's source position (X, Y, Z coordinates in model space) to the clipboard. This position can be pasted to other control points or objects requiring position data.

When to use it

  • Duplicating positions for multiple control points
  • Transferring positions between objects
  • Recording specific coordinate locations
  • Creating control points at identical positions

Notes Copies source position only, not target position. For tie points connecting two coordinate systems, this copies the "from" position.

Paste Position​

Menu name: Paste Position Tooltip Paste position from clipboard to control point.

What it does Applies a previously copied position to the selected control point's source position. This updates where the control point is located in model/image space.

When to use it

  • Applying consistent positions across multiple control points
  • Correcting control point positions with known coordinates
  • Duplicating control point locations

Notes Updates source position. Target position (real-world coordinates) remains unchanged. Useful for positioning control points at precisely measured locations.

Paste Target Position​

Menu name: Paste Target Position Tooltip Paste position to control point's target (real-world) coordinates.

What it does Applies a previously copied position to the selected control point's target position (real-world georeferenced coordinates). This updates the control point's correspondence in the target coordinate system.

When to use it

  • Applying surveyed coordinates to control points
  • Updating target coordinates from GPS measurements
  • Correcting real-world positions for georeferencing

Notes Updates target position only - source position in model space remains unchanged. Target position is typically in real-world coordinate systems (latitude/longitude, projected coordinates, etc.). Essential for establishing accurate georeferencing.

Organisation​

Move Up in List​

Menu name: Move Up in List Tooltip Move control point up in display list.

What it does Moves the control point up one position in the project tree and control point list order. This changes the order in which control points appear in lists and dialogues. Purely organisational - does not affect georeferencing calculations.

When to use it

  • Organising control points by importance or workflow order
  • Grouping related control points together
  • Customising control point display order
  • Prioritising high-quality control points

Notes Only affects display order, not data or calculations. Top control point cannot be moved up further. Order is saved with the project.

Move Down in List​

Menu name: Move Down in List Tooltip Move control point down in display list.

What it does Moves the control point down one position in the project tree and control point list order. This changes the order in which control points appear in lists and dialogues. Purely organisational - does not affect georeferencing calculations.

When to use it

  • Organising control points by importance or workflow order
  • Moving low-quality control points to bottom
  • Customising control point display order

Notes Only affects display order, not data or calculations. Bottom control point cannot be moved down further.

Menu name: Re-link Image Tooltip Reconnect control point to a different or relocated image.

What it does Opens dialogue to select a replacement image file for the control point. This is useful when image files have been moved, renamed, or when the control point should reference a different image. Updates the control point's image file reference without changing position data.

When to use it

  • Fixing broken image links after file reorganisation
  • Updating control points after moving project files
  • Redirecting control points to corrected/updated images
  • Reconnecting control points when image paths have changed

Notes

Link Repair

Only updates the file path reference. Control point position (pixel coordinates in image, if applicable) remains unchanged. Ensure the replacement image is geometrically similar to avoid misalignment.

Common after moving projects between systems or reorganising file structures. Control point assumes pixel coordinates still correspond to same location in replacement image.

Object Operations​

Export​

Menu name: Export Tooltip Export control point data to file.

What it does See Export in Shared Commands for complete documentation. Opens export dialogue to save control point data to external file formats. Export includes source positions (model coordinates), target positions (real-world coordinates), and any associated attributes or measurements.

When to use it

  • Sharing control point data with collaborators
  • Archiving georeferencing information
  • Exporting for use in GIS or surveying software
  • Creating backup of georeferencing data

Notes Export formats typically include CSV or text files with coordinate pairs. Both source and target positions are usually exported. Essential for documenting georeferencing and enabling recreation in other software.

Delete​

Menu name: Delete Tooltip Permanently remove control point from project.

What it does See Delete in Shared Commands for complete documentation. Permanently removes the control point from the project database. If the control point was being used for georeferencing calculations, removing it may affect alignment accuracy.

When to use it

  • Removing erroneous control points
  • Deleting low-quality measurements
  • Cleaning up redundant control points
  • Removing outliers from georeferencing

Notes

Affects Georeferencing

Deleting control points may change georeferencing transformation if point was used in calculations. Georeferencing may need to be recalculated after deletion. Consider disabling rather than deleting if uncertain.

Cannot be undone. If control point is critical for alignment, ensure adequate remaining control points before deletion.

Group Operations​

When right-clicking a Control Point Group (folder), additional commands are available:

Spreadsheet View​

Menu name: Spreadsheet View Tooltip View all control points in spreadsheet format.

What it does Opens a spreadsheet view displaying all control points in the group with their properties in tabular format. Columns typically include source coordinates (X, Y, Z in model), target coordinates (georeferenced X, Y, Z), residual errors, image links, and quality metrics. Allows sorting, filtering, and batch editing.

When to use it

  • Reviewing all control points systematically
  • Identifying control points with large errors
  • Batch editing control point properties
  • Quality control of georeferencing data
  • Exporting control point tables

Notes Spreadsheet is typically editable - changes update control points in 3D model. Useful for finding outliers by sorting on residual error column. Can highlight problematic control points for review or deletion.

Import From Cameras...​

Menu name: From Cameras... Tooltip Import control points from camera/photogrammetry solution.

What it does Opens dialogue to import control points derived from photogrammetry camera solutions or bundle adjustment results. Extracts tie points, camera positions, or object points from photogrammetry projects, converting them to VRGS control points for georeferencing or alignment.

When to use it

  • Importing photogrammetry results
  • Using camera solution tie points for georeferencing
  • Transferring control points from external photogrammetry software
  • Leveraging bundle adjustment results

Notes

Photogrammetry Integration

Camera solutions contain precisely computed 3D positions from image matching. These make excellent control points if real-world coordinates are known for some positions.

Import format depends on photogrammetry software. Common formats include Bundler output, VisualSFM, Agisoft markers, or similar formats. May import hundreds or thousands of points - consider filtering or decimation.

Between Coordinate Systems (CRS)​

Menu name: Between Coordinate Systems (CRS) Tooltip Transform all control point coordinates between coordinate systems.

What it does Opens dialogue to transform control point positions from one coordinate reference system to another. Applies coordinate transformation to all control points in the group, updating either source or target positions depending on selection.

When to use it

  • Converting project to different coordinate system
  • Aligning control points with updated coordinate definitions
  • Standardising control points to common reference system
  • Correcting coordinate system errors

Notes Transformation affects all control points in group simultaneously. Requires valid coordinate system definitions for source and target. Accuracy depends on transformation definition quality. Essential when integrating data from different coordinate systems.

Copy Tiepoint List​

Menu name: Copy Tiepoint List Tooltip Copy all control points to clipboard as list.

What it does Copies all control points in the group to the clipboard as a structured list. The list includes source positions, target positions, and attributes for all control points. Can be pasted into spreadsheet applications or back into VRGS control point groups.

When to use it

  • Duplicating control point sets between projects
  • Exporting control point data to spreadsheets
  • Creating backup copies of control point configurations
  • Transferring control points between groups

Notes List format typically includes all control point data in tab-delimited or CSV format. Can be pasted directly into Excel or similar applications. Useful for documenting or archiving georeferencing configurations.

Paste Tiepoint List​

Menu name: Paste Tiepoint List Tooltip Paste control points from clipboard list.

What it does Imports control points from a previously copied tie point list on the clipboard. Creates new control points in the group based on the pasted data (source positions, target positions, attributes).

When to use it

  • Importing control points from spreadsheets
  • Duplicating control point sets from other projects
  • Restoring control point configurations
  • Batch creating control points from coordinate lists

Notes Pasted data must match expected format (coordinate pairs, attributes). Useful for programmatically creating control points or transferring between projects. Validates data format before import.

Reset Target Positions​

Menu name: Reset Target Positions Tooltip Clear target (real-world) coordinates for all control points.

What it does Resets the target positions (real-world georeferenced coordinates) of all control points in the group to undefined or default values. Source positions (model coordinates) are preserved. This allows re-entering or recalculating target coordinates whilst keeping control point locations in the model.

When to use it

  • Starting georeferencing process over with existing control points
  • Clearing incorrect real-world coordinates
  • Preparing control points for new survey data
  • Resetting after coordinate system changes

Notes

Removes Georeferencing

This removes real-world coordinate data. Georeferencing/alignment will be lost until target positions are re-specified. Source positions (where control points are in the model) are preserved.

Use when control point locations are correct but real-world coordinates need to be re-determined. Cannot be undone.

Menu name: Re-link Images Tooltip Batch reconnect all control points to relocated images.

What it does Opens dialogue to batch update image file references for all control points in the group. Useful when image files have been moved or renamed en masse. Can specify new image folder location or path transformation rules to update all control point image links simultaneously.

When to use it

  • Fixing broken image links after bulk file moves
  • Updating control points after project reorganisation
  • Redirecting to new image file locations
  • Repairing links after transferring projects between systems

Notes

Batch Operation

Updates image file paths for all control points. Can use path substitution (replace old path with new path) or folder relocation. Control point pixel coordinates remain unchanged.

Much faster than re-linking individual control points when many images have moved together. Verify one control point after operation to ensure links are correct.