A reference may be a tool, e.g. a point or based on a point and a line or an edge of an object in the image. Most tools return a reference system. A blob tool will return the center of the major blob. A line finder a reference based on one of the located lines.

References in Scorpion can handle translation, rotation, scaling and perspective. Any number of references may be defined and combined in Scorpion. 

The following reference tools are available in Scorpion:

• Calibrator - defines a reference system using a high precision grid - handles lens distortion, lens and camera magnification
• ExternalReference - useful for working in an external reference system - typically a robot
• ChangeLineReference - changes reference system for a line
• ChangePointReference - changes reference system for a point
• MoveReference - translates and / or rotates a reference system
• PointLineReference - creates a reference system based on a point and a line
• ScaleReference - changes the x and y scale of a reference system
• ChangeReference - a powerful combination of ScaleReference and MoveReference with the ability to scale the reference system with respect to a user defined center or image center
• ModifyReference - calculates the change between two references and applies this change to a third reference

The Calibrator tool handles lens distortion, lens magnification and camera magnification using a Nth order nonlinear calibration based on a precision grid. The Calibrator is essential for making high precision 2D and 3D robot vision and gauging systems.

In robot guiding the robot calibration is normally performed by ExternalReference which provides a standard four, five or six point calibration.