Create and calibrate a subject

Calibrating a subject involves having a performer wearing the required marker set stand in an A-pose and then perform a Range of Motion (ROM) in the capture volume. During the ROM, ensure that the performer goes through a full range of movement for every limb and joint that is to be captured.

Before you begin, to give the clearest view of the subject, at the top of the 3D Scene view, ensure View Filters is selected, then under the Volume options, clear Cameras. In the Subjects section, select Solve and in the options matrix, in the S column, ensure Skin is selected (in addition to any other options that you may want to use).

If you want to set aside a part of your volume for subject calibration, to avoid having to clear the volume each time you have to calibrate or re-calibrate a subject, see Create a subject calibration hotspot in Getting more from Vicon Shogun.

High fidelity fingers marker sets

If you're using a marker set that includes markers for high fidelity fingers, note that labeling also makes use of this feature. To help the calibration, ensure you have placed offset markers on the upper arms and legs.

To perform live subject calibration:

1. In the Tracking panel, on the Setup tab, in the Template field, choose the appropriate template for your subject.
   If you're using side waist markers and/or finger markers, make sure you choose the templates that include side waist markers and/or fingers (indicated by their names).
2. To choose a mesh, ensure the Advanced properties are displayed (if they aren't, click Show Advanced at the top right of the Setup tab) and from the Skin list, select the mesh that is to be used for the solving skeleton.
3. To select a labeling cluster, for example, for a subject who is wearing a high density marker set (ie finger markers or any other high density set), ensure the Advanced properties are displayed and in the Labeling Cluster Selection field, make the required selection:

   • All: Any currently unattached labeling cluster will be attached to the subject.

   • Selected: Only the cluster(s) selected at the start of calibration will be attached to the subject.

   • None: No labeling clusters are used for calibration.

4. In the Subject field, enter a name for the new subject and select Create.

   

5. Have the performer wearing the correct marker set (see Place markers on a performer) enter the volume and stand in an A-pose, with the hands flat.

   

   If you're using a template that includes fingers, also ensure that:
   • The wrists are straight, not bent to either side or up or down.
   • The fingers are straight, with a natural spread, and no bend.
   • The thumb is held tight against the index finger. Ensure that the thumb and the fingers all point in the same direction.
6. On the menu bar, above the workspace, Subject Calibration Active and a flashing red circle is displayed.
   In the 3D Scene view, the markers are labeled, and the labeling and solving skeleton is displayed.Look for feedback in top right of view pane, which shows the number of markers found and the number of markers required, as well as other calibration feedback.

   

7. Visually check that all the markers have been labeled and everything looks OK.

   Tip: To quickly check that all the required markers have been placed on the performer, ensure the subject is selected and check the Marker Selection counter (bottom right of the view pane). For more information, see Check the marker count on the current selection.

8. After waiting until you’re happy with the position of the joints, on the Setup tab below the Subject field, click Accept A-Pose.
   
   

   Tip: If, despite using offset and left and right markers (see the guidance on marker placement for finger marker sets), you still experience problems with subject booting, in the Tracking panel, ensure the Setup tab is selected with Advanced options displayed, and in the Capture section, select Capture Canceled Calibrations. (This enables Support to troubleshoot your issue.)

9. Get the performer to perform a ROM (Range Of Motion) that includes all the required movement. If you're using one of the high-fidelity fingers templates, include some finger movements as part of this process. Include bending and spreading the fingers as well as poses of the hand that will be useful for checking the accuracy of the labeling.
   Include the following in your ROM:
   
   • Fists
   • Wiggle the fingers
   • Touch the tip of the thumb against the tip of each digit of the same hand:
     • Thumb to index finger
     • Thumb to middle finger
     • Thumb to ring finger
     • Thumb to pinkie
10. When the ROM is complete, select Stop Calibrating.
    In the 3D Scene, you can see the mesh and solving skeleton of the subject (if you need to change the display, at the top left of the workspace, click View Filters and choose the required options).
    At the top of the Tracking panel, a subject with the name you supplied in Step 1 above is displayed, together with a node representing its labeling cluster (if any).

    

    The subject is now fully calibrated and can be used in captures as required (for example, if you're using it for retargeting, see Load a retargeting setup).

If you have difficulty with calibrating your subject satisfactorily, see Troubleshoot subject calibration.

Check the marker count of the current selection

The Marker Selection counter enables you to easily check the number of markers currently selected. This is useful during subject calibration, if you need to check that the required number of markers have all been placed on a subject, or within a particular set of markers (for example, facial markers).

To display the number of selected markers:

1. In the 3D Scene view, ensure View Filters is selected and in the Overlays section, select the Selected Marker Count option.

   

2. At the bottom right of the view pane, the Marker Selection count is displayed. If no markers are currently selected, a zero is displayed.

   

3. As you select markers in the view pane, the Marker Selection counter changes to display the number of selected markers.