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  • Users should be able to export data from Online ami to directly compare to psana
  • could we develop an automatic gain calibration algorithm
  • radial integration with fitting of center, distance and offsets for powder rings would speed things up (like fit2d)

From XPP:
The mentioned aspects are features that our users never used, we do all 'manually' dark and gain, and during beamtime usually only dark.

What is probably missing is

  • a global database for all detectors, for geometry and dark and gain, and tools that provide filepath and eventually Data logically derived from timestamp.
  • Automatic behavior in ami and offline ami, that can be easy overridden by the user.

The main reasons that we never apply correction tools is that they don't necessarily do the right thing. other approaches we found necessary are e.g.

  • intensity dependent gain map determined by a known signal at different intensities
  • finding singular vectors of detector dependent fluctuations and filtering their content from the Data.
  • taking local darks e.g. 1d stripes on same 2x1 that were unexposed.

Indeed, geometry is an important aspect, especially when it comes to radial integration, angular convolution, etc, that people cares about relative position of pixels between tiles, even sometimes for the 2X2. This is very typically first thing users ask.

At XPP we do a lot of scans, so filtering, rebinding, based on other detectors or event codes, is something that is needed all the time. Very few of our users uses psana. With the one case I know, the challenging part is mainly the speed, that the analysis rate (mostly filtering and averaging) barely get to 30-50 Hz, a bit slow if you want to get any live feed back during the experiment.