Calibration of a diffraction setup¶
Author: Jérôme Kieffer
Date: 20/01/2015
Keywords: Calibration
Target: Scientists
- Associated video:
- http://www.edna-site.org/pub/calibration/calib.flv
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.