Camera to Marker Line Fitting

When cameras are positioned close together, so called phantom marker may be created due to marker to camera mismatch.  In this case, phantom markers appear on a straight line between or beyond real markers and one of the cameras.  This is the maximum distance, in system units, between phantom marker and the line from camera to real marker that determines if it will be filtered out as a phantom marker.  If Relative to Max Residual is checked, then this will be multiplied by Max Residual to calculate the maximum distance.  Here's some more information about this parameter:  Tracking and Body Identification

Default is 2.5

Relative to Max Residual

If checked, Camera to Marker Line Fitting is relative to Max Residual.  In this case, Camera to Marker Line Fitting will be multiplied by Max Residual to calculate the maximum distance.

Default is Checked

Max Residual Multiplier

This is used to calculate the maximum allowed error for a Rigid Body.  It will be multiplied by Max Residual to calculate the maximum error in system units.  A Rigid Body with an error larger will be invalidated.

Default is 2.5

Min Template Points

Sets the minimum number of markers that can be used to fit a rigid body to a template.  The minimum number of markers is 3.  However, depending on the configuration of the rigid body template, using 3 markers may be ambiguous and the orientation of the rigid body may be flipped in some circumstances. 

It is recommended that you use at least 4 markers.

Use Correspondence Automode

When checked, the M4 tracker will use maximum number of markers detected to fit the rigid body to the template.

This is the recommended and default mode.

Best No of Correspondences

This is the preferred number of points to use to fit the 3D points to the template.  The actual number of points used may be smaller.  The Min Template Points specifies the minimum number of points that can be used.

Minimum No of Correspondences

Minimum number of input 3D points needed.  This can't be larger than the number of template points.