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- Upon Focusing Beam as best as possible on the YAG, you can begin scanning the minimum focus
- You should have optimized Slits and Pre-focus and Transfocator lenses
- Turn off lights
- Open Inline Camera
- LCLS Tab>DAQ Control Button>Online AMI MFX
- Inline
- Open Shutter
- On Inline Image click X/Y Selection
- Click GRAB for ROI selection> highlight a symmetric square around Beam Focus on YAG
- Projection Tab
- Sum X
- Plot Button (a new plot appears)
- In new window (Projection) click Peak Button
- In another new window (PeakFit Plot) click GRAB in the Baseline section
- In MFX Home go to TFS and middle click the RBV (MFX:TFS:MMS:21.RBV)
- Click on the baseline of your plot (noise floor)
- Select Quantity dropdown to FWHM
- Set Plot Type to Mean v Var Tab
- In the blank field middle click the Z translation position variable in
- In MFX Home go to TFS and middle click the RBV (MFX:TFS:MMS:21.RBV)
- Set bins 300, lo 0, hi 300
- Click PLOT>New window pops up (Peak plot_FWHM)
- Go back to PeakFit Plot and change Quantity to Position and click Plot button again>New Window pops up (Peak plot_position)
- CLOSE PeakFit Plot
- Go back to Projection Tab and Set it to sum Y and repeat
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If you cannot find the Minimum focus, the beam and the safety interlocks might not allow you to reach this. Here move the PreFocus to the Bottom Lens and re-tune the transfocator on the YAG. This bottom lens lightly focuses the beam compared to the mid and thus the minima will be more visible.
Current version (2024-05-05):
Transfocator scan script
- Open slits: >= 2mm
- take out time tool target!
- PV of the cameras: camViewer-c <camera name>
- Crosshairs (red below right, blue upper left)
- focus_scan
<camera name> -p for projection - focus_scan
<camera name> -s for scan - eloggrab and be merry