Two camera position method

A diffraction pattern is collected with the screen in the normal and retracted position.  The position of the same zone axes on both patterns are recorded.  In addition, the  distance between two zones separated by a known angle is measured.

Single pattern calibration

The calibration parameters are calculated automatically from one diffraction pattern.

Working distance adjustment

The above calibration methods can be repeated at two different working distances.  The calibration at other working distances is calculated from these measurements.

Calibration refinement

The calibration can be refined at any time from a previously solved pattern. This adjusts the calibration parameters until the measurement error is minimised.   If required, the refinement can be carried out to adjust the calibration in every pixel of a crystal orientation map for maps acquired at low magnification.