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The Ellipse Parameter Calibration works best using multiple images at a very well defined separation and requires no indication of the energy or distance the measurement was take at. The beam centre and detector tilts are explicitly calculated during this calibration procedure, and so cannot be fixed.

Point Parameter Calibration

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Since this process does not rely on the accuracy of an ellipse fit, the Point Parameter Calibration can be used for partial rings or very high tilts, but has the dis-advantage of needing a good set of initial parameters. Since all parameters are determined by fitting any can be fixed, for example if the energy and beam centre have already been determined.

Using DAWN calibration with pyFAI or Fit2D integration

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