Leginon

First-time Leginon setup¶

Run MSi-Ptolemy and start a new session. This session can be used for setting up and as the example session that the autoscreen base its settings and stage z height on.

1. Start the session as usual.
2. Set z to the height that is typical for this scope's eucentric height.
3. Acquire a grid atlas for the next step.

Setup Square Targeting Node¶

Set, in Blobs Settings, the script to run as /path_to/sq_finder.sh¶

Define target area size sampling in the settings next to "acquisition" target panel.¶

Enter

1. Maximal number of squares to select
2. Number of target group to sample

For example, total of 12 squares selected in 3 groups means the program divided out all blob squares with valid area range into 3 size group (small, medium,and large). It then choose 4 blob squares in each group with highest score given by Ptolemy as the output square targets. High score in Ptolemy result means it is more likely to be a good square.

Set the limits of the square area range in "Thresholded" settings.¶

You can set it directly. However, it is easier to select a number of examples targets including the smallest and the largest grid square you will choose and then click on the auto square finding tool on the toolbar. Leginon will use the example targets to set the limits of the square area.

Activate auto finding in the main settings dialog.¶

Shortest path can be applied in ordering the resulting targets as well.

Setup Exposure Targeting Node¶

Define Hole Settings¶

• the script to run as /path_to/hl_finder.sh or whatever path your shell script is located.
• the json key for threshold the result. For Ptolemy, this should be "score"
• the minimal key value to accept. For Ptolemy, the probability score range is 0-1. We tend to use a very small number to only rule out the obvious bad holes. 0.01, for example.
  

Define Ice thickness thresholding¶

Like JAHC template hole finder, you can narrow the selection in Leginon with hole statistics calculation and create template for convolution. The interface is similar to JAHC hole finder.

Define target sampling¶

For screening, you may not want all targets found to be acquired. Use Acquisition Target Sampling section to achieve this:

Settings for Target Sampling¶

Once activated, it filters the acquisition target to a maximal of the requested sample number.

(Optional) Specify and setup auto aperture selection for nodes that need to be specified.¶

If you want objective aperture to be retracted only during Grid imaging, set in its advanced settings to