check intensity at the reference target before trying to align zlp

[leginonbot]

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Author Name: Anchi Cheng (@anchi2c)
Original Redmine Issue: 9489, https://emg.nysbc.org/redmine/issues/9489
Original Date: 2020-10-29
Original Assignee: Anchi Cheng

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AutoZLP can fail in different ways if the reference area is not clear of obstruction. Sometimes, GMS function won't even return. Doing a test on the intensity can reduce crashing.

[leginonbot]

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Original Redmine Comment
Author Name: Anchi Cheng (@anchi2c)
Original Date: 2020-10-29T23:57:45Z

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The threshold is determined by images already saved with the preset. It also has a minimal threshold of 5.0.

[leginonbot]

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Original Redmine Comment
Author Name: Anchi Cheng (@anchi2c)
Original Date: 2020-11-03T22:29:49Z

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This does not work well because the preset comes often from Focus node preset sequence and therefore either fc or fa. There are usually no image saved for it. Bright image values tend to come from very different imaging parameter. Also badly aligned ZLP image can be very low intensity, too.

Left at minimal threshold for now. It does prevent calling ZLP alignment when camera is in error state which would have stalled the call, too.

[leginonbot]

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Original Redmine Comment
Author Name: Anchi Cheng (@anchi2c)
Original Date: 2020-11-10T23:57:03Z

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Changed to use the first test image to determine the threshold. This should work better.

[leginonbot]

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Original Redmine Comment
Author Name: Anchi Cheng (@anchi2c)
Original Date: 2020-11-16T22:11:39Z

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Diabled in 3.5 because its results is still wrong in certain condition.