Calibration of a diffraction setup

Associated video

Review your calibration image

As viewer, try fabio_viewer from the FabIO package If you need to pre-process your data, look at pyFAI-average. In this example we have used a “max filter” over 20 frames using pyFAI-average.

Get all additional data

  • calibrant used, here LaB6
  • the energy or the wavelength
  • detector geometry
  • masks, ...

Start pyFAI-calib

Use the man page (or –help) to see all options

Pick peaks

  • A few (5) points in the most inner
  • Increase the counter to indicate the ring number
  • Pick some extra point in outer ring
  • right click to pick a point !

Review the group of peaks

Press Enter to do so... and check the ring assignment

The position of the expected rings is overlaid to the image Un-zoom to view them !

Acquire some more control points

  • Use the recalib to extract new data-points
  • free/fix/bound then refine

Visualize the integrated patterns

  • integrate to view the integrated pattern
  • then extract a few extra rings ...
  • the geometry is displayed on the screen

Quit

All different geometries have been saved into the .poni file. It can directly be used for integration

That’s all.