Assess an alignment result

Once the alignment processing is complete, you can assess the quality of the results using the QA tool and the visualization options in the Display group on the Alignment tab.

QA tool

You can perform quality assurance on the various aspects of the alignment using the QA tool. The QA view has the following four tabs:

• Overview tab—Provides general information about the processed alignment and a statistical overview of various quality attributes. The quality attributes are organized into groups based on the type of statistic they represent. Each quality attribute has a histogram chart and a table that show the data distribution and statistical overview. The bins of the histograms are coloured to indicate the quality of the attributes and symbolize the respective alignment element on the Globe.
• Control Points tab—Provides detailed statistical information about the alignment results of the control points. Inspect the table to detect possible outliers and errors.
• Automatic Tie Points tab—Provides detailed statistical information about the alignment results of the automatic tie points. Inspect the table to detect possible outliers and errors.
• Manual Tie Points tab—Provides detailed statistical information about the alignment results of the manual tie points. Inspect this table to detect possible outliers and errors.

Tip:

To sort tables per attribute, double-click the corresponding column header. Selected points on the tables are shown as selected in the glove view. To edit selected manual tie point measurements, click Edit on the toolbars on the Control Points and Manual Tie Points tabs.

Visualization options

Once an alignment is processed, you can change the symbology of the alignment elements to represent their various attributes. Assessing the quality of the alignment in a spatial context can help you detect problematic areas, and make more informed decisions.

The visualization options are in the Display group on the Alignment tab.

Tip:

To turn the visibility of an alignment element on and off, click the toggle button in the Display group. To change the symbology of alignment elements, click the respective drop-down arrow and click the attribute.

The visualization options for each alignment element are listed below.

• Camera Poses visualization options
  • Default—Default visualization.
  • Camera—The camera corresponding to the camera pose.
  • Automatic Tie Points per Image—The number of automatic tie points extracted from each image that is used in the alignment.
  • Linked Cameras per Image—The number of cameras linked by having image measurements of the same automatic tie points.
  • Position Residuals in X—The residual of the x-coordinate component for each camera pose in the alignment.
  • Position Residuals in Y—The residual of the y-coordinate component for each camera pose in the alignment.
  • Position Residuals in Z—The residual of the z-coordinate component for each camera pose in the alignment.
  • Rotation Residuals in Omega—The residual of the omega angular component for each camera pose in the alignment.
  • Position Residuals in Phi—The residual of the phi angular component for each camera pose in the alignment.
  • Position Residuals in Kappa—The residual of the kappa angular component for each camera pose in the alignment.
• Control Points visualization options
  • Image Measurements—The number of image measurements for each control point in the alignment.
  • Cameras—The number of unique cameras for each control point in the alignment.
  • Maximum Reprojection Error—The maximum value of all reprojection errors for each control point in the alignment.
  • RMS of Reprojection Errors—The mean value of all reprojection errors for each control point in the alignment.
  • Position Residuals in X—The residual of the x-coordinate component for each control point in the alignment.
  • Position Residuals in Y—The residual of the y-coordinate component for each control point in the alignment.
  • Position Residuals in Z—The residual of the z-coordinate component for each control point in the alignment.
• Automatic Tie Points and Manual Tie Points visualization options
  • Image Measurements—The number of image measurements for each automatic or manual tie point in the alignment.
  • Cameras—The number of unique cameras for each automatic or manual tie point in the alignment.
  • Maximum Reprojection Errors—The maximum value of all reprojection errors for each automatic or manual tie point in the alignment.
  • RMS of Reprojection Errors—The mean value of all reprojection errors for each automatic or manual tie point in the alignment.