Improving Autofocusing » History » Version 1
Amber Herold, 04/23/2010 08:37 AM
| 1 | 1 | Amber Herold | h1. Improving Autofocusing |
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| 4 | 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. |
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| 8 | * Use Stage Alpha Tilt to determine defocus at the low magnification sq preset to do a rough stage-z adjustment to U-center |
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| 11 | * Refine stage-z position at the high magnification fa preset and Use beam-tilt to determine the required correction. |
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| 17 | For "Stage_Wobble" Step: |
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| 18 | * Enable = Yes |
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| 21 | * Image registration= phase correlation |
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| 24 | * Fit limit = 1000 (not used) |
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| 27 | * Correct for delta Defocus/Z between 0 and 2e-4 meters |
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| 30 | * Correction type = Stage Z |
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| 33 | * Check drift greater than 3e-10 meters/s = No |
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| 36 | * Stigmator correction = No |
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| 39 | * Stigmator Defocus Max/Min = N/A |
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| 45 | For "Z_to_Eucentric" Step, change these: |
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| 46 | * preset = fa |
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| 49 | * Correct for delta Defocus/Z between 0 and 2e-5 meters |