Leginon

h1. Improving Autofocusing

Because MSI-raster is normally used for acquiring images on negatively stained particles on continuous carbon, the intermediate mag preset (hl) often lacks contrast. To reduce focusing failure, we recommend a different focusing sequence for the Z focus node.

* Use Stage Alpha Tilt to determine defocus at the low magnification sq preset to do a rough stage-z adjustment to U-center

* Refine stage-z position at the high magnification fa preset and Use beam-tilt to determine the required correction.

For "Stage_Wobble" Step:

*  Enable = Yes

*  Image registration= phase correlation

*  Fit limit = 1000 (not used)

*  Correct for delta Defocus/Z between 0 and 2e-4 meters

*  Correction type = Stage Z

*  Check drift greater than 3e-10 meters/s = No

*  Stigmator correction = No

*  Stigmator Defocus Max/Min = N/A

For "Z_to_Eucentric" Step, change these:

*  preset = fa

*  Correct for delta Defocus/Z between 0 and 2e-5 meters

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[[Queuing Option - MSI-raster|< Queuing Option]]

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